Patent Application
20200347100
The subject matter disclosed herein is generally directed to selective delivery of nucleic acids and/or proteins.
The present invention relates to ongoing efforts to achieve selective delivery of nucleic acids and/or proteins to desired cell types. The neuronal gene Arc, which bears homology to the Gag component of Ty3/gypsy retrotransposons, exhibits biochemical properties that are reminiscent of retroviral Gag proteins (Patsuzyn et al. Cell 172(1-2):275-288 (2018); Ashley et al. Cell 172:262-274 (2018)). The Arc protein assembles into virus-like capsids both in cells and when recombinantly expressed in bacteria. Arc capsids are able to encapsulate their own mRNA, mediating their intercellular transfer in extracellular vesicles. When Arc is expressed in cells it spontaneously assembles into virus-like capsids that are exported in extracellular vesicles and transfer mRNA to neighboring cells. The human genome encodes a large number of additional proteins with homology to Gag proteins, suggesting this may be a more general mechanism of intercellular communication. Molecular characterization of mechanisms that mediate specificity of mRNA packaging, capsid release by the donor cell, and uptake by the recipient cell may enable the engineering of programmable in vivo systems for selective delivery of mRNA cargo to desired cell types.
In one aspect, the invention provides an engineered non-naturally occurring polypeptide that self-assembles into an export compartment. The polypeptide may comprise an export compartment domain that directs self-assembly of the polypeptide into the export compartment and a carrier tag. The carrier tag may comprise a programmable nucleic acid or protein binding domain that binds a target molecule to be packaged into the export compartment. The target molecule may also comprise a cargo tag.
In some embodiments the target molecule may be RNA. In some embodiments, the carrier tag may be LambdaN and the cargo tag may be BoxB. In some embodiments, the carrier tag may be L7Ae peptide and the cargo tag may be C/D box. In some embodiments, the carrier tag may be MS2 domain and the cargo tag may be MS2 RNA. In some embodiments, the carrier tag may be TAT peptide and the cargo tag may be TAR RNA.
In other embodiments, the target molecule may be protein. In some embodiments, the carrier tag may be B2 nanobody, and the cargo tag may be BC2 peptide. In some embodiments, the carrier tag may be Sun tag antibody, and the cargo tag may be Sun tag antibody. In some embodiments, the carrier tag may be SUMO domain, and the cargo tag may be SIM peptide. In some embodiments, the carrier tag may be 4WW domain, and the cargo tag may be PPXY domain.
The polypeptide may further comprise a programmable nucleic acid or protein binding domain that binds target nucleic acids or proteins to be packaged within the export compartment. In some embodiments, the export compartment domain may be engineered to provide cell-specific uptake of the assembled export compartment. The polypeptide may comprise a Gag-homology protein or functional domain thereof. The Gag-homology protein or functional domain thereof may comprise both the export compartment domain and the nucleic acid binding domain. In some embodiments, the nucleic acid binding domain may be modified relative to the native nucleic acid binding domain of the Gag-homology protein. The nucleic acid binding domain may be a non-native nucleic acid binding domain relative to the Gag-homology protein.
In some embodiments, the Gag-homology protein may be Arc or a paraneoplastic Ma antigen (PNMA) protein. The PNMA protein may be ZCC18, ZCH12, PNM8B, PNM6A, PMA6F, PMAGE, PNMA2, PNM8A, PNMA3, PNMA5, PNMA1, MOAP1, or CCD8. In some embodiments, the polypeptide may further comprise an epitope tag for expression on the surface of the export compartment. The epitope tag may be a cleavable epitope tag.
In another aspect, the invention provides a nucleic acid sequence encoding any of the polypeptides described herein. In another aspect, the invention provides a vector comprising such a nucleic acid sequence.
In another aspect, the invention provides a composition comprising any of the polypeptides, nucleic acid sequences, or vectors described herein. In some embodiments, the composition may further comprise one or more suitable pharmaceutical carriers and/or excipients.
In another aspect, the invention provides a method of sampling live cells comprising delivering a nucleic acid sequence or a vector as described herein to a target population of cells. In some embodiments, the method may comprise inducing expression of the polypeptide to induce export compartment formation and packaging of target nucleic acid and proteins and isolating export compartments comprising cellular nucleic acid and/or proteins at one or more time points.
In another aspect, the invention provides a method of delivering nucleic acids and/or proteins to cells. The method may comprise expressing a self-assembling polypeptide as described herein in a population of culture cells comprising the nucleic acids and/or proteins to be delivered, such that the nucleic acids and/or proteins are captured and packaged within export compartments by the self-assembling polypeptide. The method may further comprise isolating export compartments exported by the population of cultured cells and delivering the export compartments to a target cell or cell population for uptake by the target cell or cell population.
In another aspect, the invention provides a method of delivering nucleic acids and/or proteins between populations of cells comprising delivering a nucleic acid sequence or vector as described herein to a first population of donor cells cultured in the presence of one or more recipient cell populations. The method may further comprise expressing the self-assembling polypeptide such that target nucleic acids and/or proteins from the donor cells are packaged in export compartments and delivering the target nucleic acids and/or proteins to the one or more recipient cell populations by exporting of the export compartments from the donor cells to the one or more cell populations.
In some embodiments, delivery of the export compartment to the one or more donor cell populations is used to induce differentiation of the one or more recipient cell populations. In some embodiments, the one or more recipient populations are stem cells that are induced to differentiate into one or more cell types. In some embodiments, delivery of the export compartment to the one or more recipient cell populations may be used to induce production of one or more biomolecules by the one or more donor cell populations. The one or more biomolecules may comprise antibodies.
Delivery of the export compartment to the one or more recipient cell populations may be used to induce a shift in cell state by triggering the activating and/or silencing of one or more cell pathways. The one or more recipient populations may be isolated ex vivo cells. The isolated ex vivo cells may be modified and used for an adoptive cell therapy. Delivery of the nucleic acid sequence or vector as described herein may be done in vivo.
In some embodiments, the one or more donor populations may be at or proximate to diseased tissue, and one or more cell types that are part of the diseased tissue may be the one or more recipient cells. Uptake of the export compartments may lead to senescence or apoptosis of the one or more recipient cells. In some embodiments, uptake of the export compartments may lead to a shift in cell states within the diseased tissue that treats or ameliorates the disease.
In one aspect, the invention provides a method of producing non-naturally occurring capsids for transferring nucleic acids and/or proteins to a cell. The method may include combining in a solution, unassembled recombinant GAG-like proteins, nucleic acids and/or proteins in low salt conditions; and increasing the ionic strength of the solution, wherein the ionic strength is about the ionic strength of a 0.3 M NaCl or 0.5 M NaPO4 solution.
Some embodiments involve the addition of NaCl. Some embodiments involve the addition of NaPO4. In some embodiments, increasing the ionic strength comprises salt gradient dialysis, wherein the target ionic strength is obtained over a time course of 4-48 hours. Some embodiments further comprise encapsulating the capsid in a lipid membrane.
The GAG-like protein may be selected from the group consisting of ARC, ZCC18, ZCH12, PNM8B, PNM8B, PNM6A, PMA6F, PMA6E, PNMA2, PNM8A, PNMA3, PNMA5, PNMA1, MOAP1, and CCDC8. In specific embodiments, the GAG-like protein is ARC.
The nucleic acids and/or proteins may comprise one or more mRNAs. The nucleic acids and/or proteins may comprise one or more sequences encoding a CRISPR effector protein and one or more guide sequences specific for one or more target nucleic acids. In specific embodiments, the nucleic acids and/or proteins comprise ribonucleoproteins (RNP).
In some embodiments, the RNPs comprise a CRISPR system. The CRISPR system may comprise a CRISPR effector protein and one or more guide sequences specific for one or more target nucleic acids. The recombinant GAG-like proteins may be expressed and purified from bacteria, yeast, insect cells, or mammalian cells. The recombinant GAG-like proteins may be purified under denaturing conditions and transferred to non-denaturing conditions by buffer exchange. In some embodiments, the GAG-like proteins may comprise an epitope tag. The epitope tag may be cleaved from the GAG-like proteins before producing capsids. In some embodiments, the capsids may be purified by gradient sedimentation.
In another aspect, the invention provides a method of producing non-naturally occurring capsids for transferring nucleic acids and/or proteins to a cell. The method may include expressing in a population of cultured cells a GAG-like protein, nucleic acids and/or proteins; obtaining a cell lysate from the population of cells; and purifying capsids from the cell lysate.
In yet another aspect, the invention provides a method of producing non-naturally occurring capsids for transferring nucleic acids and/or proteins to a cell. The method may include expressing in a population of cultured cells a GAG-like protein, nucleic acids and/or proteins; and purifying extracellular vesicles comprising capsids from the cell culture media.
In some embodiments, the GAG-like protein may be tagged with an epitope tag. In some embodiments, the GAG-like protein may be tagged with a fluorescent marker. In some embodiments, the population of cells may include bacteria, yeast, insect cells, or mammalian cells. The population of cells may be mammalian neurons and the cells may be activated to release extracellular vesicles. The cells may be activated with KCl treatment.
In some embodiments, the extracellular vesicle fraction may be purified by gradient sedimentation. The purified extracellular vesicles may be treated with RNase. The GAG-like protein may be selected from the group consisting of ARC, ZCC18, ZCH12, PNM8B, PNM8B, PNM6A, PMA6F, PMA6E, PNMA2, PNM8A, PNMA3, PNMA5, PNMA1, MOAP1, and CCDC8. In some embodiments, the GAG-like protein may be ARC. The nucleic acids and/or proteins may comprise one or more sequences encoding a CRISPR effector protein and one or more guide sequences specific for one or more target nucleic acids.
In yet another aspect, the invention provides a plurality of non-naturally occurring capsids including a CRISPR system obtained by any of the methods described herein.
In yet another aspect, the invention provides a pharmaceutical composition comprising one or more of the non-naturally occurring capsids described herein.
In yet another aspect, the invention provides a method of treatment comprising administering the pharmaceutical composition described herein to a subject in need thereof.
In yet another aspect, the invention provides a method of transferring nucleic acids and/or proteins to a cell comprising introducing to one or more cells, non-naturally occurring capsids obtained by any method described herein.
These and other aspects, objects, features, and advantages of the example embodiments will become apparent to those having ordinary skill in the art upon consideration of the following detailed description of illustrated example embodiments.
An understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention may be utilized, and the accompanying drawings of which:
The figures herein are for illustrative purposes only and are not necessarily drawn to scale.
Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Definitions of common terms and techniques in molecular biology may be found in Molecular Cloning: A Laboratory Manual, 2nd edition (1989) (Sambrook, Fritsch, and Maniatis); Molecular Cloning: A Laboratory Manual, 4th edition (2012) (Green and Sambrook); Current Protocols in Molecular Biology (1987) (F. M. Ausubel et al. eds.); the series Methods in Enzymology (Academic Press, Inc.): PCR 2: A Practical Approach (1995) (M. J. MacPherson, B. D. Hames, and G. R. Taylor eds.): Antibodies, A Laboratory Manual (1988) (Harlow and Lane, eds.): Antibodies A Laboratory Manual, 2nd edition 2013 (E. A. Greenfield ed.); Animal Cell Culture (1987) (R. I. Freshney, ed.); Benjamin Lewin, Genes IX, published by Jones and Bartlet, 2008 (ISBN 0763752223); Kendrew et al. (eds.), The Encyclopedia of Molecular Biology, published by Blackwell Science Ltd., 1994 (ISBN 0632021829); Robert A. Meyers (ed.), Molecular Biology and Biotechnology: a Comprehensive Desk Reference, published by VCH Publishers, Inc., 1995 (ISBN 9780471185710); Singleton et al., Dictionary of Microbiology and Molecular Biology 2nd ed., J. Wiley & Sons (New York, N.Y. 1994), March, Advanced Organic Chemistry Reactions, Mechanisms and Structure 4th ed., John Wiley & Sons (New York, N.Y. 1992); and Marten H. Hofker and Jan van Deursen, Transgenic Mouse Methods and Protocols, 2nd edition (2011).
As used herein, the singular forms “a”, “an”, and “the” include both singular and plural referents unless the context clearly dictates otherwise.
The term “optional” or “optionally” means that the subsequent described event, circumstance or substituent may or may not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.
The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within the respective ranges, as well as the recited endpoints.
The terms “about” or “approximately” as used herein when referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, are meant to encompass variations of and from the specified value, such as variations of +/−10% or less, +1-5% or less, +/−1% or less, and +/−0.1% or less of and from the specified value, insofar such variations are appropriate to perform in the disclosed invention. It is to be understood that the value to which the modifier “about” or “approximately” refers is itself also specifically, and preferably, disclosed.
As used herein, a “biological sample” may contain whole cells and/or live cells and/or cell debris. The biological sample may contain (or be derived from) a “bodily fluid”. The present invention encompasses embodiments wherein the bodily fluid is selected from amniotic fluid, aqueous humour, vitreous humour, bile, blood serum, breast milk, cerebrospinal fluid, cerumen (earwax), chyle, chyme, endolymph, perilymph, exudates, feces, female ejaculate, gastric acid, gastric juice, lymph, mucus (including nasal drainage and phlegm), pericardial fluid, peritoneal fluid, pleural fluid, pus, rheum, saliva, sebum (skin oil), semen, sputum, synovial fluid, sweat, tears, urine, vaginal secretion, vomit and mixtures of one or more thereof. Biological samples include cell cultures, bodily fluids, cell cultures from bodily fluids. Bodily fluids may be obtained from a mammal organism, for example by puncture, or other collecting or sampling procedures.
The term “control” refers to any reference standard suitable to provide a comparison to the expression products in the test sample. In one embodiment, the control comprises obtaining a “control sample” from which expression product levels are detected and compared to the expression product levels from the test sample. Such a control sample may comprise any suitable sample, including but not limited to a sample from a control patient (can be stored sample or previous sample measurement) with a known outcome; normal tissue or cells isolated from a subject, such as a normal patient or the patient having a condition of interest (cancer is used below as a representative condition), cultured primary cells/tissues isolated from a subject such as a normal subject or the cancer patient, adjacent normal cells/tissues obtained from the same organ or body location of the cancer patient, a tissue or cell sample isolated from a normal subject, or a primary cells/tissues obtained from a depository. In another embodiment, the control may comprise a reference standard expression product level from any suitable source, including but not limited to housekeeping genes, an expression product level range from normal tissue (or other previously analyzed control sample), a previously determined expression product level range within a test sample from a group of patients, or a set of patients with a certain outcome (for example, survival for one, two, three, four years, etc.) or receiving a certain treatment (for example, standard of care cancer therapy). It will be understood by those of skill in the art that such control samples and reference standard expression product levels can be used in combination as controls in the methods of the present invention.
The term “homology” or “identity” as used herein refers to the percentage of likeness between nucleic acid molecules. To determine the homology or percent identity of two amino acid sequences or of two nucleic acid sequences, the sequences are aligned for optimal comparison purposes (e.g., gaps can be introduced in one or both of a first and a second amino acid or nucleic acid sequence for optimal alignment and non-homologous sequences can be disregarded for comparison purposes). In a preferred embodiment, the length of a reference sequence aligned for comparison purposes is at least 30%, preferably at least 40%, more preferably at least 50%, even more preferably at least 60%, and even more preferably at least 70%, 80%, or 90% of the length of the reference sequence. The amino acid residues or nucleotides at corresponding amino acid positions or nucleotide positions are then compared. When a position in the first sequence is occupied by the same amino acid residue or nucleotide as the corresponding position in the second sequence, then the molecules are identical at that position (as used herein amino acid or nucleic acid “identity” is equivalent to amino acid or nucleic acid “homology”). The percent identity between the two sequences is a function of the number of identical positions shared by the sequences, taking into account the number of gaps, and the length of each gap, which need to be introduced for optimal alignment of the two sequences.
The term “non-naturally occurring” as used herein refers to any peptide, polypeptide, protein and/or lipid coat with one or more non-naturally occurring amino acid sequences. The term also refers to a viral protein coat with at least one non-native amino acid sequence from a virus, such as herpesvirus, adenovirus, lentivirus, retrovirus, Epstein-Barr virus and vaccinia virus, and the like.
The terms “polypeptide” and “protein” are used interchangeably herein and refer to a polymer of amino acids and includes full-length proteins and fragments thereof. As will be appreciated by those skilled in the art, the invention also includes nucleic acids that encode those polypeptides having slight variations in amino acid sequences or other properties from a known amino acid sequence. Amino acid substitutions can be selected by known parameters to be neutral and can be introduced into the nucleic acid sequence encoding it by standard methods such as induced point, deletion, insertion and substitution mutants. Minor changes in amino acid sequence are generally preferred, such as conservative amino acid replacements, small internal deletions or insertions, and additions or deletions at the ends of the molecules. These modifications can result in changes in the amino acid sequence, provide silent mutations, modify a restriction site, or provide other specific mutations. Additionally, they can result in a beneficial change to the encoded protein.
The terms “subject,” “individual,” and “patient” are used interchangeably herein to refer to a vertebrate, preferably a mammal, more preferably a human. Mammals include, but are not limited to, murines, simians, humans, farm animals, sport animals, and pets. Tissues, cells and their progeny of a biological entity obtained in vivo or cultured in vitro are also encompassed.
The term “vector” as used herein refers to any element, such as a plasmid, phage, capsid, transposon, cosmid, chromosome, virus, virion, and the like, which is capable of replication when associated with the proper control elements and which can transfer gene sequences into cells. Thus, the term includes cloning and expression vehicles, as well as viral vectors.
The practice of the present invention employs, unless otherwise indicated, conventional techniques of immunology, biochemistry, chemistry, molecular biology, microbiology, cell biology, genomics and recombinant DNA, which are within the skill of the art. See MOLECULAR CLONING: A LABORATORY MANUAL, 2nd edition (1989) (Sambrook, Fritsch and Maniatis); MOLECULAR CLONING: A LABORATORY MANUAL, 4th edition (2012) (Green and Sambrook); CURRENT PROTOCOLS IN MOLECULAR BIOLOGY (1987) (F. M. Ausubel, et al. eds.); the series METHODS IN ENZYMOLOGY (Academic Press, Inc.); PCR 2: A PRACTICAL APPROACH (1995) (M. J. MacPherson, B. D. Hames and G. R. Taylor eds.); ANTIBODIES, A LABORATORY MANUAL (1988) (Harlow and Lane, eds.); ANTIBODIES A LABORATORY MANUAL, 2nd edition (2013) (E. A. Greenfield ed.); and ANIMAL CELL CULTURE (1987) (R. I. Freshney, ed.).
Various embodiments are described hereinafter. It should be noted that the specific embodiments are not intended as an exhaustive description or as a limitation to the broader aspects discussed herein. One aspect described in conjunction with a particular embodiment is not necessarily limited to that embodiment and can be practiced with any other embodiment(s). Reference throughout this specification to “one embodiment”, “an embodiment,” “an example embodiment,” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” or “an example embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention. For example, in the appended claims, any of the claimed embodiments can be used in any combination.
All publications, published patent documents, and patent applications cited herein are hereby incorporated by reference to the same extent as though each individual publication, published patent document, or patent application was specifically and individually indicated as being incorporated by reference.
In one aspect, embodiments disclosed herein provide compositions comprising engineered non-naturally occurring polypeptides that self-assemble into an export compartment.
In another aspect, embodiments disclosed herein provide methods for engineering a programmable in vivo system for selective delivery of mRNA cargo to desired cell types. In some embodiments, such methods include producing non-naturally occurring capsids for transferring nucleic acids and/or proteins to a cell. Certain embodiments involve combining unassembled recombinant GAG-like proteins, nucleic acids and/or proteins in a solution in low salt conditions, and increasing the ionic strength of the solution. Other embodiments involve expressing a GAG-like protein, nucleic acids and/or proteins in a population of cultured cells, obtaining a cell lysate from the population of cells, and purifying capsids from the cell lysate. Yet other embodiments involve expressing a GAG-like protein, nucleic acids and/or proteins in a population of cultured cells and purifying extracellular vesicles comprising capsids from the cell culture media.
In another aspect, embodiments disclosed herein provide a plurality of non-naturally occurring capsids comprising a CRISPR system obtained by any of the methods disclosed herein. Such capsids may be provided in a pharmaceutical composition, and may be introduced to one or more cells by any of the methods disclosed herein.
Also provided herein are methods of treatment using capsids, pharmaceutical compositions, or any of the methods described herein for transferring nucleic acids and/or proteins to a cell.
Export Compartments that Self-Assemble from Non-Naturally Occurring Polypeptides
Engineered non-naturally occurring polypeptides are provided that self-assemble into an export compartment. The non-naturally occurring polypeptides may comprise an export compartment domain and/or a nucleic acid binding domain. The export compartment domain and/or the nucleic acid binding domain may be modified relative to their native domains. In embodiments, the polypeptide further comprises an epitope tag.
Non-naturally occurring polypeptides can be generated by a number of known methods. Such methods include, but are not necessarily limited to, combining in a solution, unassembled recombinant GAG-like proteins, nucleic acids and/or proteins in low salt conditions.
The neuronal gene Arc bears homology to the Gag component of Ty3/gypsy retrotransposons and exhibits biochemical properties that are reminiscent of retroviral Gag proteins. The Arc protein assembles into virus-like capsids both in cells and when recombinantly expressed in bacteria. Arc capsids are able to encapsulate their own mRNA, mediating their intercellular transfer in extracellular vesicles. Purified Arc proteins may be used to reconstitute capsids with different DNA or RNA or proteins or some mixture thereof and can be packaged into the capsid for delivery into cells. In some embodiments, capsids may be assembled using lipids to aid uptake by cells. Various embodiments may utilize different Arc orthologs.
Genes encoding viral polypeptides capable of self-assembly into defective, non-self-propagating viral particles can be obtained from the genomic DNA of a DNA virus or the genomic cDNA of an RNA virus or from available subgenomic clones containing the genes. These genes will include those encoding viral capsid proteins (i.e., proteins that comprise the viral protein shell) and, in the case of enveloped viruses, such as retroviruses, the genes encoding viral envelope glycoproteins. Additional viral genes may also be required for capsid protein maturation and particle self-assembly. These may encode viral proteases responsible for processing of capsid protein or envelope glycoproteins. As an example, the genomic structure of picornaviruses has been well characterized, and the patterns of protein synthesis leading to virion assembly are clear. Rueckert, R. in Virology (1985), B. N. Fields et al. (eds.) Raven Press, New York, pp 705-738. In picornaviruses, the viral capsid proteins are encoded by an RNA genome containing a single long reading frame and are synthesized as part of a polyprotein which is processed to yield the mature capsid proteins by a combination of cellular and viral proteases. Thus, the picornavirus genes required for capsid self-assembly include both the capsid structural genes and the viral proteases required for their maturation. Another virus class from which genes encoding self-assembling capsid proteins can be isolated is the lentiviruses, of which HIV is an example. Like the picornaviral capsid proteins, the HIV gag protein is synthesized as a precursor polypeptide that is subsequently processed, by a viral protease, into the mature capsid polypeptides. However, the gag precursor polypeptide can self-assemble into virus-like particles in the absence of protein processing. Gheysen et al., Cell 59:103 (1989); Delchambre et al., The EMBO J. 8:2653-2660 (1989). Unlike picornavirus capsids, HIV capsids are surrounded by a loose membranous envelope that contains the viral glycoproteins. These are encoded by the viral env gene.
In alternative embodiments, additional human proteins with Gag homology may be used to assemble viral-like capsids that mediate intercellular mRNA transfer. Such proteins include, but are not necessarily limited to, the extended PNMA gene family including ZCC18, ZCH12, PNM8B, PNM8B, PNM6A, PMA6F, PMA6E, PNMA2, PNM8A, PNMA3, PNMA5, PNMA1, MOAP1, and CCDC8. In specific embodiments, the GAG-like protein is ARC.
In specific embodiments, nucleic acids (DNA or RNA) or proteins may be packaged into extracellular vesicles and may be used to transduce cells. In specific embodiments, purified Arc proteins may be used to reconstitute capsids with different DNA or RNA or proteins or some mixture of these, and package them into the capsid for delivery.
In some embodiments, the export compartment domain in the non-naturally occurring polypeptide described herein directs self-assembly of the polypeptide into the export compartment. In some embodiments, the polypeptide may also comprise a programmable nucleic acid or protein binding domain that binds target nucleic acids or proteins to be packaged within the export compartment.
In some embodiments, the polypeptide as described herein may comprise a Gag-homology protein or functional domain thereof.
Molecular and genetic determinants of Gag-mediated intercellular communication may be determined by characterizing the mechanisms of capsid-mediated intercellular mRNA transfer, with particular focus on features that could enable use of this system for programmable nucleic acid delivery. Different Gag proteins evolved diverse RNA-binding domains for mediating specific encapsidation of their RNA genomes. The RNA binding sequence specificity of the human Gag homology proteins can be tested through protein pull-down and sequencing of associated RNA and/or through sequencing of the extracellular vesicle fraction from HEK293 cells that over-express each protein. The nucleic-acid binding domains can be swapped between proteins, or additional RNA-binding domains with known specificity can be fused to test the extent to which binding specificity can be reprogrammed. Accordingly, the Gag-homology protein or functional domain thereof can comprise both the export compartment domain and nucleic acid binding complain.
A genetic screen can be performed on the recipient cells to better understand the pathways involved in uptake of either extracellular vesicle-enclosed or non-enveloped capsids. Recipient cells may be pre-treated with a genome-wide CRISPR knockout library. Following uptake of fluorescent signal, the cells can be sorted and guide frequency quantified by next-generation sequencing. Genetic perturbations that inhibit or enhance uptake may lead to under and over-representation of associated guides in the sorted cell population, respectively. This may reveal that uptake of enveloped or non-enveloped capsids is dependent on specific membrane receptors, which would provide a basis for engineering target cell specificity. Likewise, given that Gag homology proteins are able to transfer their own mRNA, a mutagenesis screen of the Gag protein can be performed to look for mutations that alter transfer efficiency. Following sorting the transferred mRNA in sorted recipient cells can be selectively amplified to reveal which mutations increase transfer efficiency.
The Gag-homology protein can be selected from Arc, ASPRV1, a Sushi-Class protein, a SCAN protein, or a PNMA protein. In particular instances, the Gag-homology protein is a PNMA protein, for example, ZCC18, ZCH12, PNM8B, PNM6A, PNMA6E_i2, PMA6F, PMAGE, PNMA2, PNM8A, PNMA3, PNMA5, PNMA1, MOAP1, or CCD8. In embodiments, the Gag-homology protein is an Arc protein, in certain embodiments, hARC or dARC1. The Gag-homology protein can comprise ASPRV1. In other instances, the Gag-homology protein is a Sushi-Class protein like PEG10, RTL3, RTL10, or RTL1. In certain embodiments, the Gag Homology protein is a SCAN protein, for example, PGBD1. In instances, the PEG10 Gag homology protein is PEG10_i6 or PEG10_i2.
In some embodiments, the Gag-homology protein or functional domain thereof comprises both the export compartment domain and the nucleic acid binding domain. In some embodiments, the nucleic acid binding domain is modified relative to the native nucleic acid binding domain of the Gag-homology protein. In some embodiments, the nucleic acid binding domain is a non-native nucleic acid binding domain relative to the Gag-homology protein.
In some embodiments, the polypeptides described herein may comprise a Gag-homology protein or functional domain thereof. The terms “effector domain” or “regulatory and functional domain” refer to a polypeptide sequence that has an activity other than binding to the nucleic acid sequence recognized by the nucleic acid binding domain. By combining a nucleic acid binding domain with one or more effector domains, the polypeptides of the invention may be used to target the one or more functions or activities mediated by the effector domain to a particular target DNA sequence to which the nucleic acid binding domain specifically binds.
In some embodiments, the effector domain or functional domain is a protein domain which exhibits activities which include but are not limited to transposase activity, integrase activity, recombinase activity, resolvase activity, invertase activity, protease activity, DNA methyltransferase activity, DNA demethylase activity, histone acetylase activity, histone deacetylase activity, nuclease activity, nuclear-localization signaling activity, transcriptional repressor activity, transcriptional activator activity, transcription factor recruiting activity, or cellular uptake signaling activity. Other preferred embodiments of the invention may include any combination of the activities described herein.
In some embodiments, the Gag-homology protein or functional domain thereof may comprise both the export compartment domain and the nucleic acid binding domain. In specific embodiments, the nucleic acid binding domain may be modified relative to the native nucleic acid binding domain of the Gag-homology protein. In specific embodiments, the nucleic acid binding domain may be a non-native nucleic acid binding domain relative to the Gag-homology protein. In some embodiments, the Gag-homology protein may be Arc or a paraneoplastic Ma antigen (PNMA) protein.
In some embodiments, the recombinant GAG-like proteins may be expressed and purified from bacteria, yeast, insect cells, or mammalian cells. The recombinant GAG-like proteins may be purified under denaturing conditions and transferred to non-denaturing conditions by buffer exchange.
In some embodiments, the polypeptide described herein may further comprise an epitope tag for expression on the surface of the export compartment. Epitope tags are peptide sequences that are linked to a recombinant protein. The epitope tag may be cleavable using chemical agents or by enzymatic means, such as proteolysis or intein splicing.
In some embodiments, the GAG-like proteins may comprise an epitope tag. Such epitope tags may include, but are not necessarily limited to, V5-tag, Myc-tag, HA-tag, SPOT-tag, and NE-tag. The epitope tag may be cleaved from the GAG-like proteins before producing capsids. The epitope tag can comprise a glycoprotein of vesicular stomatitis virus (VSVG). In certain embodiments, the epitope tag is a cleavable epitope tag.
In particular embodiments, the export compart is a gesicle. In preferred embodiments, the gesicle is as described in the examples and figures provided herein.
In certain example embodiments, the invention further comprises pharmaceutical compositions comprising one or more of the non-naturally occurring polypeptides or capsids described herein.
Capsids may be purified by any means known in the art, such as, but not necessarily limited to, differential centrifugation, density gradient centrifugation or gradient sedimentation, size exclusion chromatography, ultrafiltration, immune-capture, or precipitation. In specific embodiments, the capsids are purified by gradient sedimentation.
In other example embodiments, non-naturally occurring capsids for transferring nucleic acids and/or proteins to a cell may be produced by expressing in a population of cultured cells a GAG-like protein, nucleic acids and/or proteins, obtaining a cell lysate from the population of cells, and purifying capsids from the cell lysate.
In other example embodiments, non-naturally occurring capsids for transferring nucleic acids and/or proteins to a cell may be produced by expressing in a population of cultured cells a GAG-like protein, nucleic acids and/or proteins, and purifying extracellular vesicles comprising capsids from the cell culture media.
In specific embodiments, the GAG-like protein may be tagged with an epitope tag as previously described. In embodiments, the GAG-like protein may be tagged with a fluorescent marker. Suitable fluorescent tags include, but are not necessarily limited to, green fluorescent protein (GFP), yellow fluorescent protein, blue fluorescent protein, cyan fluorescent protein, mCherry, etc.
In some embodiments, the export compartment domain directs self-assembly of the polypeptide into the export compartment. In certain embodiments, cargo can be enriched by affinity tags. A variety of suitable affinity cargo/carrier tag pairs are available in the art. In some embodiments, the polypeptide may also comprise a carrier tag having a programmable nucleic acid or protein binding domain that binds a target molecule to be packaged into the export compartment. The target molecule may comprise a cargo tag. In some embodiments, the target molecule may be RNA. Suitable carrier tags for RNA cargo include, but are not necessarily limited to, LambdaN, L7Ae peptide, MS2 domain, or TAT peptide. Suitable cargo tags for RNA cargo include, but are not necessarily limited to, BoxB, C/D box, MS2 RNA, or TAR RNA. In some embodiments, the target molecule may be protein. Suitable carrier tags for protein cargo include, but are not necessarily limited to, B2 nanobody, Sun tag antibody, SUMO domain, or 4WW domain. Suitable cargo tags for protein cargo include, but are not necessarily limited to, BC2 peptide, Sun tag antibody, SIM peptide, or PPXY domain. In embodiments, cargo and carrier tags are provided in pairs that allow for enrichment of the cargo.
In some aspects or embodiments, a composition comprising an export compartment formulation may be used. The term “export compartment” as used herein, refers to any particle delivery system and/or formulation that may be used for delivery. Particle delivery systems within the scope of the present invention may be provided in any form, including but not limited to solid, semi-solid, emulsion, or colloidal particles. As such any of the delivery systems described herein, including but not limited to, e.g., lipid-based systems, liposomes, micelles, microvesicles, exosomes, or gene gun may be provided as particle delivery systems within the scope of the present invention.
In some embodiments, the export compartment domain of the non-naturally occurring polypeptides described herein may be engineered to provide cell-specific uptake of the assembled export compartment.
In general, a “nanoparticle” refers to any particle having a diameter of less than 1000 nm. In certain preferred embodiments, nanoparticles of the invention have a greatest dimension (e.g., diameter) of 500 nm or less. In other preferred embodiments, nanoparticles of the invention have a greatest dimension ranging between 25 nm and 200 nm. In other preferred embodiments, nanoparticles of the invention have a greatest dimension of 100 nm or less. In other preferred embodiments, nanoparticles of the invention have a greatest dimension ranging between 35 nm and 60 nm. It will be appreciated that reference made herein to particles or nanoparticles can be interchangeable, where appropriate.
It will be understood that the size of the particle will differ depending as to whether it is measured before or after loading. Accordingly, in particular embodiments, the term “nanoparticles” may apply only to the particles pre-loading.
Nanoparticles encompassed in the present invention may be provided in different forms, e.g., as solid nanoparticles (e.g., metal such as silver, gold, iron, titanium), non-metal, lipid-based solids, polymers), suspensions of nanoparticles, or combinations thereof. Metal, dielectric, and semiconductor nanoparticles may be prepared, as well as hybrid structures (e.g., core-shell nanoparticles). Nanoparticles made of semiconducting material may also be labeled quantum dots if they are small enough (typically sub 10 nm) that quantization of electronic energy levels occurs. Such nanoscale particles are used in biomedical applications as drug carriers or imaging agents and may be adapted for similar purposes in the present invention.
Semi-solid and soft nanoparticles have been manufactured and are within the scope of the present invention. A prototype nanoparticle of semi-solid nature is the liposome. Various types of liposome nanoparticles are currently used clinically as delivery systems for anticancer drugs and vaccines. Nanoparticles with one half hydrophilic and the other half hydrophobic are termed Janus particles and are particularly effective for stabilizing emulsions. They can self-assemble at water/oil interfaces and act as solid surfactants.
Particle characterization (including e.g., characterizing morphology, dimension, etc.) is done using a variety of different techniques. Common techniques are electron microscopy (TEM, SEM), atomic force microscopy (AFM), dynamic light scattering (DLS), X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF), ultraviolet-visible spectroscopy, dual polarization interferometry and nuclear magnetic resonance (NMR). Characterization (dimension measurements) may be made as to native particles (i.e., preloading) or after loading of the cargo (herein cargo refers to e.g., one or more components of a CRISPR-Cas system e.g., CRISPR enzyme or mRNA or guide RNA, or any combination thereof, and may include additional carriers and/or excipients) to provide particles of an optimal size for delivery for any in vitro, ex vivo and/or in vivo application of the present invention. In certain preferred embodiments, particle dimension (e.g., diameter) characterization is based on measurements using dynamic laser scattering (DLS). Mention is made of U.S. Pat. Nos. 8,709,843, 6,007,845, 5,855,913, 5,985,309, and 5,543,158; and the publication by James E. Dahlman and Carmen Barnes et al. Nature Nanotechnology (2014) published online 11 May 2014, doi:10.1038/nnano.2014.84, concerning particles, methods of making and using them and measurements thereof.
Self-assembling export compartments or nanoparticles with RNA may be constructed with polyethyleneimine (PEI) that is PEGylated with an Arg-Gly-Asp (RGD) peptide ligand attached at the distal end of the polyethylene glycol (PEG). This system has been used, for example, as a means to target tumor neovasculature expressing integrins and deliver siRNA inhibiting vascular endothelial growth factor receptor-2 (VEGF R2) expression and thereby achieve tumor angiogenesis (see, e.g., Schiffelers et al., Nucleic Acids Research, 2004, Vol. 32, No. 19). Nanoplexes may be prepared by mixing equal volumes of aqueous solutions of cationic polymer and nucleic acid to give a net molar excess of ionizable nitrogen (polymer) to phosphate (nucleic acid) over the range of 2 to 6. The electrostatic interactions between cationic polymers and nucleic acid resulted in the formation of polyplexes with average particle size distribution of about 100 nm, hence referred to here as nanoplexes. A dosage of about 100 to 200 mg of CRISPR Cas is envisioned for delivery in the self-assembling nanoparticles of Schiffelers et al.
The nanoplexes of Bartlett et al. (PNAS, Sep. 25, 2007, vol. 104, no. 39) may also be applied to the present invention. The nanoplexes of Bartlett et al. are prepared by mixing equal volumes of aqueous solutions of cationic polymer and nucleic acid to give a net molar excess of ionizable nitrogen (polymer) to phosphate (nucleic acid) over the range of 2 to 6. The electrostatic interactions between cationic polymers and nucleic acid resulted in the formation of polyplexes with average particle size distribution of about 100 nm, hence referred to here as nanoplexes. The DOTA-siRNA of Bartlett et al. was synthesized as follows: 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid mono(N-hydroxysuccinimide ester) (DOTA-NHSester) was ordered from Macrocyclics (Dallas, Tex.). The amine modified RNA sense strand with a 100-fold molar excess of DOTA-NHS-ester in carbonate buffer (pH 9) was added to a microcentrifuge tube. The contents were reacted by stirring for 4 h at room temperature. The DOTA-RNAsense conjugate was ethanol-precipitated, resuspended in water, and annealed to the unmodified antisense strand to yield DOTA-siRNA. All liquids were pretreated with Chelex-100 (Bio-Rad, Hercules, Calif.) to remove trace metal contaminants. Tf-targeted and nontargeted siRNA nanoparticles may be formed by using cyclodextrin-containing polycations. Typically, nanoparticles were formed in water at a charge ratio of 3 (+/−) and an siRNA concentration of 0.5 g/liter. One percent of the adamantane-PEG molecules on the surface of the targeted nanoparticles were modified with Tf (adamantane-PEG-Tf). The nanoparticles were suspended in a 5% (wt/vol) glucose carrier solution for injection.
The lipid particles developed by the Qiaobing Xu's lab at Tufts University may be used/adapted to the present delivery system. See Wang et al., J. Control Release, 2017 Jan. 31. pii: 50168-3659(17)30038-X. doi: 10.1016/j.jconrel.2017.01.037. [Epub ahead of print]; Altino{hacek over (g)}lu et al., Biomater Sci., 4(12):1773-80, Nov. 15, 2016; Wang et al., PNAS, 113(11):2868-73 Mar. 15, 2016; Wang et al., PloS One, 10(11): e0141860. doi: 10.1371/journal.pone.0141860. eCollection 2015, Nov. 3, 2015; Takeda et al., Neural Regen Res. 10(5):689-90, May 2015; Wang et al., Adv. Healthc Mater., 3(9):1398-403, Sep. 2014; and Wang et al., Agnew Chem Int Ed Engl., 53(11):2893-8, Mar. 10, 2014.
US Patent Publication No. 2011/0293703 relating to lipidoid compounds describes embodiments that are also particularly useful in the administration of polynucleotides, which may be applied to the delivery systems of the present invention. In one aspect, the aminoalcohol lipidoid compounds are combined with an agent to be delivered to a cell or a subject to form microparticles, nanoparticles, liposomes, or micelles. The agent to be delivered by the particles, liposomes, or micelles may be in the form of a gas, liquid, or solid, and the agent may be a polynucleotide, protein, peptide, or small molecule. The aminoalcohol lipidoid compounds may be combined with other aminoalcohol lipidoid compounds, polymers (synthetic or natural), surfactants, cholesterol, carbohydrates, proteins, lipids, etc. to form the particles. These particles may then optionally be combined with a pharmaceutical excipient to form a pharmaceutical composition.
US Patent Publication No. 2011/0293703 also provides methods of preparing the aminoalcohol lipidoid compounds. One or more equivalents of an amine are allowed to react with one or more equivalents of an epoxide-terminated compound under suitable conditions to form an aminoalcohol lipidoid compound of the present invention. In certain embodiments, all the amino groups of the amine are fully reacted with the epoxide-terminated compound to form tertiary amines. In other embodiments, all the amino groups of the amine are not fully reacted with the epoxide-terminated compound to form tertiary amines thereby resulting in primary or secondary amines in the aminoalcohol lipidoid compound. These primary or secondary amines are left as is or may be reacted with another electrophile such as a different epoxide-terminated compound. As will be appreciated by one skilled in the art, reacting an amine with less than excess of epoxide-terminated compound will result in a plurality of different aminoalcohol lipidoid compounds with various numbers of tails. Certain amines may be fully functionalized with two epoxide-derived compound tails while other molecules will not be completely functionalized with epoxide-derived compound tails. For example, a diamine or polyamine may include one, two, three, or four epoxide-derived compound tails off the various amino moieties of the molecule resulting in primary, secondary, and tertiary amines. In certain embodiments, all the amino groups are not fully functionalized. In certain embodiments, two of the same types of epoxide-terminated compounds are used. In other embodiments, two or more different epoxide-terminated compounds are used. The synthesis of the aminoalcohol lipidoid compounds is performed with or without solvent, and the synthesis may be performed at higher temperatures ranging from 30-100° C., preferably at approximately 50-90° C. The prepared aminoalcohol lipidoid compounds may be optionally purified. For example, the mixture of aminoalcohol lipidoid compounds may be purified to yield an aminoalcohol lipidoid compound with a particular number of epoxide-derived compound tails. Or the mixture may be purified to yield a particular stereo- or regioisomer. The aminoalcohol lipidoid compounds may also be alkylated using an alkyl halide (e.g., methyl iodide) or other alkylating agent, and/or they may be acylated.
US Patent Publication No. 2011/0293703 also provides libraries of aminoalcohol lipidoid compounds prepared by the inventive methods. These aminoalcohol lipidoid compounds may be prepared and/or screened using high-throughput techniques involving liquid handlers, robots, microtiter plates, computers, etc. In certain embodiments, the aminoalcohol lipidoid compounds are screened for their ability to transfect polynucleotides or other agents (e.g., proteins, peptides, small molecules) into the cell.
US Patent Publication No. 2013/0302401 relates to a class of poly(beta-amino alcohols) (PBAAs) that are prepared using combinatorial polymerization. The inventive PBAAs may be used in biotechnology and biomedical applications as coatings (such as coatings of films or multilayer films for medical devices or implants), additives, materials, excipients, non-biofouling agents, micropatterning agents, and cellular encapsulation agents. When used as surface coatings, these PBAAs elicited different levels of inflammation, both in vitro and in vivo, depending on their chemical structures. The large chemical diversity of this class of materials allowed us to identify polymer coatings that inhibit macrophage activation in vitro. Furthermore, these coatings reduce the recruitment of inflammatory cells, and reduce fibrosis, following the subcutaneous implantation of carboxylated polystyrene microparticles. These polymers may be used to form polyelectrolyte complex capsules for cell encapsulation. The invention may also have many other biological applications such as antimicrobial coatings, DNA or siRNA delivery, and stem cell tissue engineering. The teachings of US Patent Publication No. 2013/0302401 may be applied to a CRISPR Cas system or any other system of the present invention.
In another embodiment, lipid nanoparticles (LNPs) are contemplated. An antitransthyretin small interfering RNA has been encapsulated in lipid nanoparticles and delivered to humans (see, e.g., Coelho et al., N Engl J Med 2013; 369:819-29), and such a system may be adapted and applied to a CRISPR Cas system or any other system of the present invention. Doses of about 0.01 to about 1 mg per kg of body weight administered intravenously are contemplated. Medications to reduce the risk of infusion-related reactions are contemplated, such as dexamethasone, acetaminophen, diphenhydramine or cetirizine, and ranitidine. Multiple doses of about 0.3 mg per kilogram every 4 weeks for five doses are also contemplated.
Zhu et al. (US Patent Publication No. 2014/0348900) provides for a process for preparing liposomes, lipid discs, and other lipid nanoparticles using a multi-port manifold, wherein the lipid solution stream, containing an organic solvent, is mixed with two or more streams of aqueous solution (e.g., buffer). In some aspects, at least some of the streams of the lipid and aqueous solutions are not directly opposite of each other. Thus, the process does not require dilution of the organic solvent as an additional step. In some embodiments, one of the solutions may also contain an active pharmaceutical ingredient (API). This invention provides a robust process of liposome manufacturing with different lipid formulations and different payloads. Particle size, morphology, and the manufacturing scale can be controlled by altering the port size and number of the manifold ports, and by selecting the flow rate or flow velocity of the lipid and aqueous solutions.
Cullis et al. (US Patent Publication No. 2014/0328759) provides limit size lipid nanoparticles with a diameter from 10-100 nm, in particular comprising a lipid bilayer surrounding an aqueous core. Methods and apparatus for preparing such limit size lipid nanoparticles are also disclosed.
Manoharan et al. (US Patent Publication No 2014/0308304) provides cationic lipids of formula (I)
or a salt thereof, wherein X is N or P; R′ is absent, hydrogen, or alkyl; with respect to R1 and R2, (i) R1 and R2 are each, independently, optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, heterocycle or R10; (ii) R1 and R2, together with the nitrogen atom to which they are attached, form an optionally substituted heterocyclic ring; or (iii) one of R1 and R2 is optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, or heterocycle, and the other forms a 4-10 member heterocyclic ring or heteroaryl with (a) the adjacent nitrogen atom and (b) the (R)a group adjacent to the nitrogen atom; each occurrence of R is, independently, —(CR3R4)-; each occurrence of R3 and R4 are, independently H, halogen, OH, alkyl, alkoxy, —NH.sub.2, alkylamino, or dialkylamino; or R3 and R4, together with the carbon atom to which they are directly attached, form a cycloalkyl group, wherein no more than three R groups in each chain attached to the atom X* are cycloalkyl; each occurrence of R.sup.10 is independently selected from PEG and polymers based on poly(oxazoline), poly(ethylene oxide), poly(vinyl alcohol), poly(glycerol), poly(N-vinylpyrrolidone), poly [N-(2-hydroxypropyl)methacrylamide] and poly(amino acid)s, wherein (i) the PEG or polymer is linear or branched, (ii) the PEG or polymer is polymerized by n subunits, (iii) n is a number-averaged degree of polymerization between 10 and 200 units, and (iv) wherein the compound of formula has at most two R10 groups; Q is absent or is —O—, —NH—, —C(O)O—, —OC(O)—, —C(O)N(R4)-, —N(R5)C(O)—, —S—S—, OC(O)O—, —O—N.dbd.C(R5)-, —C(R5).dbd.N—O—, —OC(O)N(R5)-, —N(R5)C(O)N(R5)-, —N(R5)C(O)O—, —C(O)S—, —C(S)O— or —C(R5).dbd.N—O—C(O)—; Q1 and Q2 are each, independently, absent, —O—, —OC(O)—, —C(O)O—, —SC(O)—, —C(O)S—, —OC(S)—, —C(S)O—, —S—S—, —C(O)(NR5)-, —N(R5)C(O)—, —C(S)(NR5)-, —N(R5)C(O)—, —N(R5)C(O)N(R5)-, or —OC(O)O—; Q3 and Q4 are each, independently, H, —(CR3R4)-, aryl, or a cholesterol moiety; each occurrence of A1, A2, A3 and A4 is, independently, —(CR5R5-CR5.dbd.CR5)-; each occurrence of R5 is, independently, H or alkyl; M1 and M2 are each, independently, a biodegradable group (e.g., —OC(O)—, —C(O)O—, —SC(O)—, —C(O)S—, —OC(S)—, —C(S)O—, —S—S—, —C(R5).dbd.N—, —N.dbd.C(R5)-, —C(R5).dbd.N—O—, —O—N.dbd.C(R5)-, —C(O)(NR5)-, —N(R5)C(O)—, —C(S)(NR5)-, —N(R5)C(O)—, —N(R5)C(O)N(R5)-, OC(O)O—, —0Si(R5).sub.2O—, —C(O)(CR3R4)C(O)O—, or —OC(O)(CR3R4)C(O)—); Z is absent, alkylene or —O—P(O)(OH)—O—; each attached to Z is an optional bond, such that when Z is absent, Q3 and Q4 are not directly covalently bound together; a is 1, 2, 3, 4, 5 or 6; b is 0, 1, 2, or 3; c, d, e, f, i, j, m, n, q and r are each, independently, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10; g and h are each, independently, 0, 1 or 2; k and 1 are each, independently, 0 or 1, where at least one of k and 1 is 1; and o and p are each, independently, 0, 1 or 2, wherein Q3 and Q4 are each, independently, separated from the tertiary atom marked with an asterisk (X*) by a chain of 8 or more atoms. The cationic lipid can be used with other lipid components such as cholesterol and PEG-lipids to form lipid nanoparticles with oligonucleotides, to facilitate the cellular uptake and endosomal escape, and to knockdown target mRNA both in vitro and in vivo.
LNPs have been shown to be highly effective in delivering siRNAs to the liver (see, e.g., Tabernero et al., Cancer Discovery, April 2013, Vol. 3, No. 4, pages 363-470) and are therefore contemplated for delivering RNA encoding CRISPR Cas to the liver. A dosage of about four doses of 6 mg/kg of the LNP every two weeks may be contemplated. Tabernero et al. demonstrated that tumor regression was observed after the first 2 cycles of LNPs dosed at 0.7 mg/kg, and by the end of 6 cycles the patient had achieved a partial response with complete regression of the lymph node metastasis and substantial shrinkage of the liver tumors. A complete response was obtained after 40 doses in this patient, who has remained in remission and completed treatment after receiving doses over 26 months. Two patients with RCC and extrahepatic sites of disease including kidney, lung, and lymph nodes that were progressing following prior therapy with VEGF pathway inhibitors had stable disease at all sites for approximately 8 to 12 months, and a patient with PNET and liver metastases continued on the extension study for 18 months (36 doses) with stable disease.
However, the charge of the LNP must be taken into consideration, as cationic lipids combined with negatively charged lipids induce nonbilayer structures that facilitate intracellular delivery. Because charged LNPs are rapidly cleared from circulation following intravenous injection, ionizable cationic lipids with pKa values below 7 were developed (see, e.g., Rosin et al, Molecular Therapy, vol. 19, no. 12, pages 1286-2200, Dec. 2011). Negatively charged polymers such as RNA may be loaded into LNPs at low pH values (e.g., pH 4) where the ionizable lipids display a positive charge. However, at physiological pH values, the LNPs exhibit a low surface charge compatible with longer circulation times. Four species of ionizable cationic lipids have been focused upon, namely 1,2-dilineoyl-3-dimethylammonium-propane (DLinDAP), 1,2-dilinoleyloxy-3-N,N-dimethylaminopropane (DLinDMA), 1,2-dilinoleyloxy-keto-N,N-dimethyl-3-aminopropane (DLinKDMA), and 1,2-dilinoleyl-4-(2-dimethylaminoethyl)[1,3]-dioxolane (DLinKC2-DMA). It has been shown that LNP siRNA systems containing these lipids exhibit remarkably different gene silencing properties in hepatocytes in vivo, with potencies varying according to the series DLinKC2-DMA>DLinKDMA>DLinDMA>>DLinDAP employing a Factor VII gene silencing model (see, e.g., Rosin et al, Molecular Therapy, vol. 19, no. 12, pages 1286-2200, Dec. 2011). A dosage of 1 μg/ml of LNP or CRISPR-Cas RNA in or associated with the LNP may be contemplated, especially for a formulation containing DLinKC2-DMA.
Preparation of LNPs and CRISPR Cas encapsulation may be used/and or adapted from Rosin et al, Molecular Therapy, vol. 19, no. 12, pages 1286-2200, Dec. 2011). The cationic lipids 1,2-dilineoyl-3-dimethylammonium-propane (DLinDAP), 1,2-dilinoleyloxy-3-N,N-dimethylaminopropane (DLinDMA), 1,2-dilinoleyloxyketo-N,N-dimethyl-3-aminopropane (DLinK-DMA), 1,2-dilinoleyl-4-(2-dimethylaminoethyl)-[1,3]-dioxolane (DLinKC2-DMA), (3-o-[2″-(methoxypolyethyleneglycol 2000) succinoyl]-1,2-dimyristoyl-sn-glycol (PEG-S-DMG), and R-3-[(w-methoxy-poly(ethylene glycol)2000) carbamoyl]-1,2-dimyristyloxlpropyl-3-amine (PEG-C-DOMG) may be provided by Tekmira Pharmaceuticals (Vancouver, Canada) or synthesized. Cholesterol may be purchased from Sigma (St Louis, Mo.). The specific CRISPR Cas RNA may be encapsulated in LNPs containing DLinDAP, DLinDMA, DLinK-DMA, and DLinKC2-DMA (cationic lipid:DSPC:CHOL: PEGS-DMG or PEG-C-DOMG at 40:10:40:10 molar ratios). When required, 0.2% SP-DiOC18 (Invitrogen, Burlington, Canada) may be incorporated to assess cellular uptake, intracellular delivery, and biodistribution. Encapsulation may be performed by dissolving lipid mixtures comprised of cationic lipid:DSPC:cholesterol:PEG-c-DOMG (40:10:40:10 molar ratio) in ethanol to a final lipid concentration of 10 mmol/1. This ethanol solution of lipid may be added drop-wise to 50 mmol/1 citrate, pH 4.0 to form multilamellar vesicles to produce a final concentration of 30% ethanol vol/vol. Large unilamellar vesicles may be formed following extrusion of multilamellar vesicles through two stacked 80 nm Nucleopore polycarbonate filters using the Extruder (Northern Lipids, Vancouver, Canada). Encapsulation may be achieved by adding RNA dissolved at 2 mg/ml in 50 mmol/1 citrate, pH 4.0 containing 30% ethanol vol/vol drop-wise to extruded preformed large unilamellar vesicles and incubation at 31° C. for 30 minutes with constant mixing to a final RNA/lipid weight ratio of 0.06/1 wt/wt. Removal of ethanol and neutralization of formulation buffer were performed by dialysis against phosphate-buffered saline (PBS), pH 7.4 for 16 hours using Spectra/Por 2 regenerated cellulose dialysis membranes. Nanoparticle size distribution may be determined by dynamic light scattering using a NICOMP 370 particle sizer, the vesicle/intensity modes, and Gaussian fitting (Nicomp Particle Sizing, Santa Barbara, Calif.). The particle size for all three LNP systems may be ˜70 nm in diameter. RNA encapsulation efficiency may be determined by removal of free RNA using VivaPureD MiniH columns (Sartorius Stedim Biotech) from samples collected before and after dialysis. The encapsulated RNA may be extracted from the eluted nanoparticles and quantified at 260 nm. RNA to lipid ratio was determined by measurement of cholesterol content in vesicles using the Cholesterol E enzymatic assay from Wako Chemicals USA (Richmond, Va.). In conjunction with the herein discussion of LNPs and PEG lipids, PEGylated liposomes or LNPs are likewise suitable for delivery of a CRISPR-Cas system or components thereof.
Preparation of large LNPs may be used/and or adapted from Rosin et al, Molecular Therapy, vol. 19, no. 12, pages 1286-2200, Dec. 2011. A lipid premix solution (20.4 mg/ml total lipid concentration) may be prepared in ethanol containing DLinKC2-DMA, DSPC, and cholesterol at 50:10:38.5 molar ratios. Sodium acetate may be added to the lipid premix at a molar ratio of 0.75:1 (sodium acetate:DLinKC2-DMA). The lipids may be subsequently hydrated by combining the mixture with 1.85 volumes of citrate buffer (10 mmol/1, pH 3.0) with vigorous stirring, resulting in spontaneous liposome formation in aqueous buffer containing 35% ethanol. The liposome solution may be incubated at 37° C. to allow for time-dependent increase in particle size. Aliquots may be removed at various times during incubation to investigate changes in liposome size by dynamic light scattering (Zetasizer Nano Z S, Malvern Instruments, Worcestershire, UK). Once the desired particle size is achieved, an aqueous PEG lipid solution (stock=10 mg/ml PEG-DMG in 35% (vol/vol) ethanol) may be added to the liposome mixture to yield a final PEG molar concentration of 3.5% of total lipid. Upon addition of PEG-lipids, the liposomes should their size, effectively quenching further growth. RNA may then be added to the empty liposomes at an RNA to total lipid ratio of approximately 1:10 (wt:wt), followed by incubation for 30 minutes at 37° C. to form loaded LNPs. The mixture may be subsequently dialyzed overnight in PBS and filtered with a 0.45-μm syringe filter.
In some embodiments, the LNP also includes at least one helper lipid. In some embodiments, the helper lipid is selected from phospholipids and steroids. In some embodiments, the phospholipids are di- and/or monoester of the phosphoric acid. In some embodiments, the phospholipids are phosphoglycerides and/or sphingolipids. In some embodiments, the steroids are naturally occurring and/or synthetic compounds based on the partially hydrogenated cyclopenta[a]phenanthrene. In some embodiments, the steroids contain 21 to 30 C atoms. In some embodiments, the steroid is cholesterol. In some embodiments, the helper lipid is selected from 1,2-diphytanoyl-sn-glycero-3-phosphoethanolamine (DPhyPE), ceramide, and 1,2-dioleylsn-glycero-3-phosphoethanolamine (DOPE).
In some embodiments, the at least one helper lipid comprises a moiety selected from the group comprising a PEG moiety, a HEG moiety, a polyhydroxyethyl starch (polyHES) moiety and a polypropylene moiety. In some embodiments, the moiety has a molecule weight between about 500 to 10,000 Da or between about 2,000 to 5,000 Da. In some embodiments, the PEG moiety is selected from 1,2-distearoyl-sn-glycero-3 phosphoethanolamine, 1,2-dialkyl-sn-glycero-3-phosphoethanolamine, and Ceramide-PEG. In some embodiments, the PEG moiety has a molecular weight between about 500 to 10,000 Da or between about 2,000 to 5,000 Da. In some embodiments, the PEG moiety has a molecular weight of 2,000 Da.
In some embodiments, the helper lipid is between about 20 mol % to 80 mol % of the total lipid content of the composition. In some embodiments, the helper lipid component is between about 35 mol % to 65 mol % of the total lipid content of the LNP. In some embodiments, the LNP includes lipids at 50 mol % and the helper lipid at 50 mol % of the total lipid content of the LNP.
In some embodiments, the second helper lipid is between about 0.05 mol % to 4.9 mol % or between about 1 mol % to 3 mol % of the total lipid content. In some embodiments, the LNP includes lipids at between about 45 mol % to 50 mol % of the total lipid content, a first helper lipid between about 45 mol % to 50 mol % of the total lipid content, under the proviso that there is a PEGylated second helper lipid between about 0.1 mol % to 5 mol %, between about 1 mol % to 4 mol %, or at about 2 mol % of the total lipid content, wherein the sum of the content of the lipids, the first helper lipid, and of the second helper lipid is 100 mol % of the total lipid content and wherein the sum of the first helper lipid and the second helper lipid is 50 mol % of the total lipid content. In some embodiments, the LNP comprises: (a) 50 mol % of β-arginyl-2,3-diamino propionic acid-N-palmityl-N-oleyl-amide trihydrochloride, 48 mol % of 1,2-diphytanoyl-sn-glycero-3-phosphoethanolamine; and 2 mol % 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-PEG2000; or (b) 50 mol % of β-arginyl-2,3-diamino propionic acid-N-palmityl-N-oleyl-amide trihydrochloride, 49 mol % 1,2-diphytanoyl-sn-glycero-3-phosphoethanolamine; and 1 mol % N(Carbonyl-methoxypolyethylenglycol-2000)-1,2-distearoyl-sn-glycero3-phosphoethanolamine, or a sodium salt thereof. In some embodiments, the LNP contains a nucleic acid, wherein the charge ratio of nucleic acid backbone phosphates to cationic lipid nitrogen atoms is about 1:1.5-7 or about 1:4.
In some embodiments, the LNP also includes a shielding compound, which is removable from the lipid composition under in vivo conditions. In some embodiments, the shielding compound is a biologically inert compound. In some embodiments, the shielding compound does not carry any charge on its surface or on the molecule as such. In some embodiments, the shielding compounds are polyethylenglycoles (PEGs), hydroxyethylglucose (HEG) based polymers, polyhydroxyethyl starch (polyHES) and polypropylene. In some embodiments, the PEG, HEG, polyHES, and a polypropylene weigh between about 500 to 10,000 Da or between about 2000 to 5000 Da. In some embodiments, the shielding compound is PEG2000 or PEG5000.
In some embodiments, the LNP includes at least one lipid, a first helper lipid, and a shielding compound that is removable from the lipid composition under in vivo conditions. In some embodiments, the LNP also includes a second helper lipid. In some embodiments, the first helper lipid is ceramide. In some embodiments, the second helper lipid is ceramide. In some embodiments, the ceramide comprises at least one short carbon chain substituent of from 6 to 10 carbon atoms. In some embodiments, the ceramide comprises 8 carbon atoms. In some embodiments, the shielding compound is attached to a ceramide. In some embodiments, the shielding compound is attached to a ceramide. In some embodiments, the shielding compound is covalently attached to the ceramide. In some embodiments, the shielding compound is attached to a nucleic acid in the LNP. In some embodiments, the shielding compound is covalently attached to the nucleic acid. In some embodiments, the shielding compound is attached to the nucleic acid by a linker. In some embodiments, the linker is cleaved under physiological conditions. In some embodiments, the linker is selected from ssRNA, ssDNA, dsRNA, dsDNA, peptide, S—S-linkers and pH sensitive linkers. In some embodiments, the linker moiety is attached to the 3′ end of the sense strand of the nucleic acid. In some embodiments, the shielding compound comprises a pH-sensitive linker or a pH-sensitive moiety. In some embodiments, the pH-sensitive linker or pH-sensitive moiety is an anionic linker or an anionic moiety. In some embodiments, the anionic linker or anionic moiety is less anionic or neutral in an acidic environment. In some embodiments, the pH-sensitive linker or the pH-sensitive moiety is selected from the oligo (glutamic acid), oligophenolate(s) and diethylene triamine penta acetic acid.
In any of the LNP embodiments in the previous paragraph, the LNP can have an osmolality between about 50 to 600 mosmole/kg, between about 250 to 350 mosmole/kg, or between about 280 to 320 mosmole/kg, and/or wherein the LNP formed by the lipid and/or one or two helper lipids and the shielding compound have a particle size between about 20 to 200 nm, between about 30 to 100 nm, or between about 40 to 80 nm.
In some embodiments, sugar-based particles may be used, for example GalNAc, as described herein and with reference to WO2014118272 (incorporated herein by reference) and Nair, J K et al., 2014, Journal of the American Chemical Society 136 (49), 16958-16961) and the teaching herein, especially in respect of delivery applies to all particles unless otherwise apparent. This may be considered to be a sugar-based particle and further details on other particle delivery systems and/or formulations are provided herein. GalNAc can therefore be considered to be a particle in the sense of the other particles described herein, such that general uses and other considerations, for instance delivery of said particles, apply to GalNAc particles as well. A solution-phase conjugation strategy may for example be used to attach triantennary GalNAc clusters (mol. wt. ˜2000) activated as PFP (pentafluorophenyl) esters onto 5′-hexylamino modified oligonucleotides (5′-HA ASOs, mol. wt. ˜8000 Da; Ostergaard et al., Bioconjugate Chem., 2015, 26 (8), pp 1451-1455). Similarly, poly(acrylate) polymers have been described for in vivo nucleic acid delivery (see International Patent Publication No. WO 2013/158141 incorporated herein by reference). In further alternative embodiments, pre-mixing CRISPR nanoparticles (or protein complexes) with naturally occurring serum proteins may be used in order to improve delivery (Akinc A et al, 2010, Molecular Therapy vol. 18 no. 7, 1357-1364).
Literature that may be employed in conjunction with herein teachings include: Cutler et al., J. Am. Chem. Soc. 2011 133:9254-9257, Hao et al., Small. 2011 7:3158-3162, Zhang et al., ACS Nano. 2011 5:6962-6970, Cutler et al., J. Am. Chem. Soc. 2012 134:1376-1391, Young et al., Nano Lett. 2012 12:3867-71, Zheng et al., Proc. Natl. Acad. Sci. USA. 2012 109:11975-80, Mirkin, Nanomedicine 2012 7:635-638 Zhang et al., J. Am. Chem. Soc. 2012 134:16488-1691, Weintraub, Nature 2013 495:S14-S16, Choi et al., Proc. Natl. Acad. Sci. USA. 2013 110(19):7625-7630, Jensen et al., Sci. Transl. Med. 5, 209ra152 (2013) and Mirkin, et al., Small, 10:186-192.
Measurement of cell-to-cell transfer may be evaluated at multiple steps as described in Patsuzyn et al. (Cell 172(1-2):275-288; 2018). In specific embodiments, indirect testing of capsid formation in transfected HEK293 cells may be done by chemical cross-linking followed by SDS-PAGE to probe for appearance of higher molecular weight bands corresponding to protein oligomers. Export in extracellular vesicles may be performed by purifying the extracellular vesicle fraction from the media following transfection and using western blots to look for the protein in addition to reported extracellular vesicle markers. Finally, the ability of capsid-containing extracellular vesicles to be taken up by recipient cells may be tested by placing either the media or the purified extracellular vesicle fraction from cells transfected with a GFP-tagged Gag onto untransfected cells and looking for uptake of fluorescence using microscopy and/or FACS. In addition to extracellular vesicle-mediated transfer, recombinant Arc can form capsids in vitro that transfer enclosed RNA to recipient cells in the absence of an endosomal membrane. The proteins may also be either purified from bacteria or translated in vitro and tested for this activity. The formation of capsid structures in the different assays may be confirmed using methods including, but not necessarily limited to, electron microscopy, dynamic light scattering, or Spectradyne particle analysis.
Particle delivery systems within the scope of the present invention may be provided in any form, including but not limited to solid, semi-solid, emulsion, or colloidal particles. As such any of the delivery systems described herein, including but not limited to, e.g., lipid-based systems, liposomes, micelles, microvesicles, exosomes, or gene gun may be provided as particle delivery systems within the scope of the present invention.
Exosomes (or extracellular vesicles) are endogenous nano-vesicles that transport RNAs and proteins, and which can deliver RNA to the brain and other target organs. To reduce immunogenicity, Alvarez-Erviti et al. (2011, Nat Biotechnol 29: 341) used self-derived dendritic cells for exosome production. Targeting to the brain was achieved by engineering the dendritic cells to express Lamp2b, an exosomal membrane protein, fused to the neuron-specific RVG peptide. Purified exosomes were loaded with exogenous RNA by electroporation. Intravenously injected RVG-targeted exosomes delivered GAPDH siRNA specifically to neurons, microglia, oligodendrocytes in the brain, resulting in a specific gene knockdown. Pre-exposure to RVG exosomes did not attenuate knockdown, and non-specific uptake in other tissues was not observed. The therapeutic potential of exosome-mediated siRNA delivery was demonstrated by the strong mRNA (60%) and protein (62%) knockdown of BACE1, a therapeutic target in Alzheimer's disease.
In another embodiment, the plasma exosomes of Wahlgren et al. (Nucleic Acids Research, 2012, Vol. 40, No. 17 e130) are contemplated. Exosomes are nano-sized vesicles (30-90 nm in size) produced by many cell types, including dendritic cells (DC), B cells, T cells, mast cells, epithelial cells and tumor cells. These vesicles are formed by inward budding of late endosomes and are then released to the extracellular environment upon fusion with the plasma membrane. Because exosomes naturally carry RNA between cells, this property may be useful in gene therapy, and from this disclosure can be employed in the practice of the instant invention.
Exosomes from plasma can be prepared by centrifugation of buffy coat at 900 g for 20 min to isolate the plasma followed by harvesting cell supernatants, centrifuging at 300 g for 10 min to eliminate cells and at 16 500 g for 30 min followed by filtration through a 0.22 mm filter. Exosomes are pelleted by ultracentrifugation at 120 000 g for 70 min. Chemical transfection of siRNA into exosomes is carried out according to the manufacturer's instructions in RNAi Human/Mouse Starter Kit (Quiagen, Hilden, Germany). siRNA is added to 100 ml PBS at a final concentration of 2 mmol/ml. After adding HiPerFect transfection reagent, the mixture is incubated for 10 min at RT. In order to remove the excess of micelles, the exosomes are re-isolated using aldehyde/sulfate latex beads. The chemical transfection of CRISPR Cas into exosomes may be conducted similarly to siRNA. The exosomes may be co-cultured with monocytes and lymphocytes isolated from the peripheral blood of healthy donors. Therefore, it may be contemplated that exosomes containing CRISPR Cas may be introduced to monocytes and lymphocytes of and autologously reintroduced into a human. Accordingly, delivery or administration according to the invention may be performed using plasma exosomes.
Also contemplated within the scope of the invention are liposomes. Liposomes are spherical vesicle structures composed of a uni- or multilamellar lipid bilayer surrounding internal aqueous compartments and a relatively impermeable outer lipophilic phospholipid bilayer. Liposomes have gained considerable attention as drug delivery carriers because they are biocompatible, nontoxic, can deliver both hydrophilic and lipophilic drug molecules, protect their cargo from degradation by plasma enzymes, and transport their load across biological membranes and the blood brain barrier (BBB) (see, e.g., Spuch and Navarro, Journal of Drug Delivery, vol. 2011, Article ID 469679, 12 pages, 2011. doi:10.1155/2011/469679 for review).
Liposomes can be made from several different types of lipids; however, phospholipids are most commonly used to generate liposomes as drug carriers. Although liposome formation is spontaneous when a lipid film is mixed with an aqueous solution, it can also be expedited by applying force in the form of shaking by using a homogenizer, sonicator, or an extrusion apparatus (see, e.g., Spuch and Navarro, Journal of Drug Delivery, vol. 2011, Article ID 469679, 12 pages, 2011. doi:10.1155/2011/469679 for review).
Several other additives may be added to liposomes in order to modify their structure and properties. For instance, either cholesterol or sphingomyelin may be added to the liposomal mixture in order to help stabilize the liposomal structure and to prevent the leakage of the liposomal inner cargo. Further, liposomes are prepared from hydrogenated egg phosphatidylcholine or egg phosphatidylcholine, cholesterol, and dicetyl phosphate, and their mean vesicle sizes were adjusted to about 50 and 100 nm. (see, e.g., Spuch and Navarro, Journal of Drug Delivery, vol. 2011, Article ID 469679, 12 pages, 2011. doi:10.1155/2011/469679 for review).
A liposome formulation may be mainly comprised of natural phospholipids and lipids such as 1,2-di stearoryl-sn-glycero-3-phosphatidyl choline (DSPC), sphingomyelin, egg phosphatidylcholines and monosialoganglioside. Since this formulation is made up of phospholipids only, liposomal formulations have encountered many challenges, one of the ones being the instability in plasma. Several attempts to overcome these challenges have been made, specifically in the manipulation of the lipid membrane. One of these attempts focused on the manipulation of cholesterol. Addition of cholesterol to conventional formulations reduces rapid release of the encapsulated bioactive compound into the plasma or 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) increases the stability (see, e.g., Spuch and Navarro, Journal of Drug Delivery, vol. 2011, Article ID 469679, 12 pages, 2011. doi:10.1155/2011/469679 for review).
In a particularly advantageous embodiment, Trojan Horse liposomes (also known as Molecular Trojan Horses) are desirable and protocols may be found at http://cshprotocols.cshlp.org/content/2010/4/pdb.prot5407.long. These particles allow delivery of a transgene to the entire brain after an intravascular injection. Without being bound by limitation, it is believed that neutral lipid particles with specific antibodies conjugated to their surfaces allow crossing of the blood brain barrier via endocytosis. Applicant postulates utilizing Trojan Horse Liposomes to deliver the CRISPR family of nucleases to the brain via an intravascular injection, which would allow whole brain transgenic animals without the need for embryonic manipulation. About 1-5 g of DNA or RNA may be contemplated for in vivo administration in liposomes.
The vesicle composition and concentration may be selected to cause fusion of the vesicles with the cell without causing cell lysis. The fusogenic activity versus toxicity of a vesicle preparation and conditions for cell fusion and material transfer can be tested and optimized with cells in vitro. The fusogenic activity of vesicles can be modulated by forming the vesicles with a blend of non-phospholipids composed of a highly fusogenic non-phospholipid and a non-fusogenic phospholipid. For example, the fusogenic activity of vesicles containing polyoxyethylene (2) cetyl ether can be downmodulated by incorporating batyl alcohol into the vesicles. Formation of blended lipid vesicles is described in U.S. Pat. No. 5,260,065, the disclosure of which is incorporated herein by reference. Additionally, a vesicle in which the primary wall forming material is non-phospholipid material can further include a phospholipid.
When a material is to be delivered specifically to a particular type of cell but the vesicle is delivered to a location proximate to more than one type of cell (e.g., many in vivo situations), the vesicle can be directed to the target cell of interest by incorporating a targeting molecule into the vesicle. The targeting molecule functions to seek out the target cell of interest and bind to the target cell, thereby directing the vesicle to the target cell. Preferred targeting molecules include antibodies, e.g. monoclonal antibodies, which bind to a surface structure on the target cell of interest, ligands for receptors on the surface of the target cell of interest and vital proteins, e.g. membrane proteins from enveloped viruses, which mediate binding of the virus to a particular cell type. The targeting molecule can be modified such that it can be incorporated into the lipid bilayer of the vesicle. For example, a soluble protein can be provided with a hydrophobic anchor molecule which allows the protein to be tethered to the lipid vesicle. Alternatively, a targeting molecule can be incorporated using a bispecific coupling reagent, such as by the procedure disclosed in U.S. Pat. No. 5,000,960 (incorporated herein by reference). In this procedure, thiocholesterol is first incorporated into the non-phospholipid vesicle and then a coupling reagent which is reactive with sulfhydryl and amino groups is used to crosslink proteins, via their amino groups, to the vesicle, via the sulfhydryl group of thiocholesterol.
When a non-phospholipid vesicle encapsulating a biologically active material contains a targeting molecule, the vesicle can be delivered to a cell by delivering the vesicle to a location proximate to the cell and allowing the targeting molecule to seek the cell. When the cell to which the biologically active material is to be delivered is in vivo, e.g., in a mammal, the vesicle can be delivered to the cell by delivering the vesicle to the bloodstream of the mammal and allowing the targeting molecule to seek the cell.
In one preferred embodiment, the invention provides non-naturally occurring capsids produced by combining in a solution, unassembled recombinant GAG-like proteins, nucleic acids and/or proteins in low salt conditions; and increasing the ionic strength of the solution, wherein the ionic strength is about the ionic strength of a 0.3 M NaCl or 0.5 M NaPO4 solution.
In another preferred embodiment, the invention provides non-naturally occurring capsids produced by expressing in a population of cultured cells a GAG-like protein, nucleic acids and/or proteins; obtaining a cell lysate from the population of cells; and purifying capsids from the cell lysate.
In another preferred embodiment, the invention provides non-naturally occurring capsids produced by expressing in a population of cultured cells a GAG-like protein, nucleic acids and/or proteins; and purifying extracellular vesicles comprising capsids from the cell culture media.
In specific embodiments, unassembled recombinant GAG-like proteins, nucleic acids and/or proteins are combined in solution in low salt conditions.
In specific embodiments, the ionic strength of the solution may be increased, wherein the ionic strength is about the ionic strength of a 0.3 M NaCl or 0.5 M NaPO4 solution. In some embodiments, increasing ionic strength comprises salt gradient dialysis, wherein the target ionic strength is obtained over a time course of 4-48 hours.
Some embodiments involve the addition of NaCl to the solution of GAG-like proteins, nucleic acids and/or proteins. Other embodiments involve the addition of NaPO4.
In certain embodiments, the nucleic acids used for encapsulation and/or transfer to cells may be one or more mRNAs.
Embodiments disclosed herein may be used to deliver a number of synthetic small molecules and/or biological molecules. Such synthetic small molecules and/or biological molecules may include, but are not necessarily limited to, RNA, DNA, protein, peptides, antibodies, enzymes, sugars, lipids, amino acids, fatty acids, phenolic compounds, or other molecules.
In certain embodiments, the nucleic acids and/or proteins used for encapsulation and/or transfer to cells may be a site-specific nuclease or one or more sequences encoding a site specific nuclease.
As disclosed herein editing can be made by way of the transcription activator-like effector nucleases (TALENs) system. Transcription activator-like effectors (TALEs) can be engineered to bind practically any desired DNA sequence. Exemplary methods of genome editing using the TALEN system can be found for example in Cermak T. Doyle EL. Christian M. Wang L. Zhang Y. Schmidt C, et al. Efficient design and assembly of custom TALEN and other TAL effector-based constructs for DNA targeting. Nucleic Acids Res. 2011; 39:e82; Zhang F. Cong L. Lodato S. Kosuri S. Church GM. Arlotta P Efficient construction of sequence-specific TAL effectors for modulating mammalian transcription. Nat Biotechnol. 2011; 29:149-153 and U.S. Pat. Nos. 8,450,471, 8,440,431 and 8,440,432, all of which are specifically incorporated by reference.
In advantageous embodiments of the invention, the methods provided herein use isolated, non-naturally occurring, recombinant or engineered DNA binding proteins that comprise TALE monomers as a part of their organizational structure that enable the targeting of nucleic acid sequences with improved efficiency and expanded specificity.
Naturally occurring TALEs or “wild type TALEs” are nucleic acid binding proteins secreted by numerous species of proteobacteria. TALE polypeptides contain a nucleic acid binding domain composed of tandem repeats of highly conserved monomer polypeptides that are predominantly 33, 34 or 35 amino acids in length and that differ from each other mainly in amino acid positions 12 and 13. In advantageous embodiments the nucleic acid is DNA. As used herein, the term “polypeptide monomers”, or “TALE monomers” will be used to refer to the highly conserved repetitive polypeptide sequences within the TALE nucleic acid binding domain and the term “repeat variable di-residues” or “RVD” will be used to refer to the highly variable amino acids at positions 12 and 13 of the polypeptide monomers. As provided throughout the disclosure, the amino acid residues of the RVD are depicted using the IUPAC single letter code for amino acids. A general representation of a TALE monomer which is comprised within the DNA binding domain is X1-11-(X12X13)-X14-33 or 34 or 35, where the subscript indicates the amino acid position and X represents any amino acid. X12X13 indicate the RVDs. In some polypeptide monomers, the variable amino acid at position 13 is missing or absent and in such polypeptide monomers, the RVD consists of a single amino acid. In such cases the RVD may be alternatively represented as X*, where X represents X12 and (*) indicates that X13 is absent. The DNA binding domain comprises several repeats of TALE monomers and this may be represented as (X1-11-(X12X13)-X14-33 or 34 or 35)z, where in an advantageous embodiment, z is at least 5 to 40. In a further advantageous embodiment, z is at least 10 to 26.
The TALE monomers have a nucleotide binding affinity that is determined by the identity of the amino acids in its RVD. For example, polypeptide monomers with an RVD of NI preferentially bind to adenine (A), polypeptide monomers with an RVD of NG preferentially bind to thymine (T), polypeptide monomers with an RVD of HD preferentially bind to cytosine (C) and polypeptide monomers with an RVD of NN preferentially bind to both adenine (A) and guanine (G). In yet another embodiment of the invention, polypeptide monomers with an RVD of IG preferentially bind to T. Thus, the number and order of the polypeptide monomer repeats in the nucleic acid binding domain of a TALE determines its nucleic acid target specificity. In still further embodiments of the invention, polypeptide monomers with an RVD of NS recognize all four base pairs and may bind to A, T, G or C. The structure and function of TALEs is further described in, for example, Moscou et al., Science 326:1501 (2009); Boch et al., Science 326:1509-1512 (2009); and Zhang et al., Nature Biotechnology 29:149-153 (2011), each of which is incorporated by reference in its entirety.
The TALE polypeptides used in methods of the invention are isolated, non-naturally occurring, recombinant or engineered nucleic acid-binding proteins that have nucleic acid or DNA binding regions containing polypeptide monomer repeats that are designed to target specific nucleic acid sequences.
As described herein, polypeptide monomers having an RVD of HN or NH preferentially bind to guanine and thereby allow the generation of TALE polypeptides with high binding specificity for guanine containing target nucleic acid sequences. In a preferred embodiment of the invention, polypeptide monomers having RVDs RN, NN, NK, SN, NH, KN, HN, NQ, HH, RG, KH, RH and SS preferentially bind to guanine. In a much more advantageous embodiment of the invention, polypeptide monomers having RVDs RN, NK, NQ, HH, KH, RH, SS and SN preferentially bind to guanine and thereby allow the generation of TALE polypeptides with high binding specificity for guanine containing target nucleic acid sequences. In an even more advantageous embodiment of the invention, polypeptide monomers having RVDs HH, KH, NH, NK, NQ, RH, RN and SS preferentially bind to guanine and thereby allow the generation of TALE polypeptides with high binding specificity for guanine containing target nucleic acid sequences. In a further advantageous embodiment, the RVDs that have high binding specificity for guanine are RN, NH RH and KH. Furthermore, polypeptide monomers having an RVD of NV preferentially bind to adenine and guanine. In more preferred embodiments of the invention, polypeptide monomers having RVDs of H*, HA, KA, N*, NA, NC, NS, RA, and S* bind to adenine, guanine, cytosine and thymine with comparable affinity.
The predetermined N-terminal to C-terminal order of the one or more polypeptide monomers of the nucleic acid or DNA binding domain determines the corresponding predetermined target nucleic acid sequence to which the TALE polypeptides will bind. As used herein the polypeptide monomers and at least one or more half polypeptide monomers are “specifically ordered to target” the genomic locus or gene of interest. In plant genomes, the natural TALE-binding sites always begin with a thymine (T), which may be specified by a cryptic signal within the non-repetitive N-terminus of the TALE polypeptide; in some cases this region may be referred to as repeat 0. In animal genomes, TALE binding sites do not necessarily have to begin with a thymine (T) and TALE polypeptides may target DNA sequences that begin with T, A, G or C. The tandem repeat of TALE monomers always ends with a half-length repeat or a stretch of sequence that may share identity with only the first 20 amino acids of a repetitive full length TALE monomer and this half repeat may be referred to as a half-monomer (
As described in Zhang et al., Nature Biotechnology 29:149-153 (2011), TALE polypeptide binding efficiency may be increased by including amino acid sequences from the “capping regions” that are directly N-terminal or C-terminal of the DNA binding region of naturally occurring TALEs into the engineered TALEs at positions N-terminal or C-terminal of the engineered TALE DNA binding region. Thus, in certain embodiments, the TALE polypeptides described herein further comprise an N-terminal capping region and/or a C-terminal capping region.
As used herein the predetermined “N-terminus” to “C terminus” orientation of the N-terminal capping region, the DNA binding domain comprising the repeat TALE monomers and the C-terminal capping region provide structural basis for the organization of different domains in the d-TALEs or polypeptides of the invention.
The entire N-terminal and/or C-terminal capping regions are not necessary to enhance the binding activity of the DNA binding region. Therefore, in certain embodiments, fragments of the N-terminal and/or C-terminal capping regions are included in the TALE polypeptides described herein.
In certain embodiments, the TALE polypeptides described herein contain a N-terminal capping region fragment that included at least 10, 20, 30, 40, 50, 54, 60, 70, 80, 87, 90, 94, 100, 102, 110, 117, 120, 130, 140, 147, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260 or 270 amino acids of an N-terminal capping region. In certain embodiments, the N-terminal capping region fragment amino acids are of the C-terminus (the DNA-binding region proximal end) of an N-terminal capping region. As described in Zhang et al., Nature Biotechnology 29:149-153 (2011), N-terminal capping region fragments that include the C-terminal 240 amino acids enhance binding activity equal to the full length capping region, while fragments that include the C-terminal 147 amino acids retain greater than 80% of the efficacy of the full length capping region, and fragments that include the C-terminal 117 amino acids retain greater than 50% of the activity of the full-length capping region.
In some embodiments, the TALE polypeptides described herein contain a C-terminal capping region fragment that included at least 6, 10, 20, 30, 37, 40, 50, 60, 68, 70, 80, 90, 100, 110, 120, 127, 130, 140, 150, 155, 160, 170, 180 amino acids of a C-terminal capping region. In certain embodiments, the C-terminal capping region fragment amino acids are of the N-terminus (the DNA-binding region proximal end) of a C-terminal capping region. As described in Zhang et al., Nature Biotechnology 29:149-153 (2011), C-terminal capping region fragments that include the C-terminal 68 amino acids enhance binding activity equal to the full length capping region, while fragments that include the C-terminal 20 amino acids retain greater than 50% of the efficacy of the full length capping region.
In certain embodiments, the capping regions of the TALE polypeptides described herein do not need to have identical sequences to the capping region sequences provided herein. Thus, in some embodiments, the capping region of the TALE polypeptides described herein have sequences that are at least 50%, 60%, 70%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identical or share identity to the capping region amino acid sequences provided herein. Sequence identity is related to sequence homology. Homology comparisons may be conducted by eye, or more usually, with the aid of readily available sequence comparison programs. These commercially available computer programs may calculate percent (%) homology between two or more sequences and may also calculate the sequence identity shared by two or more amino acid or nucleic acid sequences. In some preferred embodiments, the capping region of the TALE polypeptides described herein have sequences that are at least 95% identical or share identity to the capping region amino acid sequences provided herein.
Sequence homologies may be generated by any of a number of computer programs known in the art, which include but are not limited to BLAST or FASTA. Suitable computer program for carrying out alignments like the GCG Wisconsin Bestfit package may also be used. Once the software has produced an optimal alignment, it is possible to calculate % homology, preferably % sequence identity. The software typically does this as part of the sequence comparison and generates a numerical result.
In advantageous embodiments described herein, the TALE polypeptides of the invention include a nucleic acid binding domain linked to the one or more effector domains. The terms “effector domain” or “regulatory and functional domain” refer to a polypeptide sequence that has an activity other than binding to the nucleic acid sequence recognized by the nucleic acid binding domain. By combining a nucleic acid binding domain with one or more effector domains, the polypeptides of the invention may be used to target the one or more functions or activities mediated by the effector domain to a particular target DNA sequence to which the nucleic acid binding domain specifically binds.
In some embodiments of the TALE polypeptides described herein, the activity mediated by the effector domain is a biological activity. For example, in some embodiments the effector domain is a transcriptional inhibitor (i.e., a repressor domain), such as an mSin interaction domain (SID). SID4X domain or a Kruppel-associated box (KRAB) or fragments of the KRAB domain. In some embodiments the effector domain is an enhancer of transcription (i.e. an activation domain), such as the VP16, VP64 or p65 activation domain. In some embodiments, the nucleic acid binding is linked, for example, with an effector domain that includes but is not limited to a transposase, integrase, recombinase, resolvase, invertase, protease, DNA methyltransferase, DNA demethylase, histone acetylase, histone deacetylase, nuclease, transcriptional repressor, transcriptional activator, transcription factor recruiting, protein nuclear-localization signal or cellular uptake signal.
In some embodiments, the effector domain is a protein domain which exhibits activities which include but are not limited to transposase activity, integrase activity, recombinase activity, resolvase activity, invertase activity, protease activity, DNA methyltransferase activity, DNA demethylase activity, histone acetylase activity, histone deacetylase activity, nuclease activity, nuclear-localization signaling activity, transcriptional repressor activity, transcriptional activator activity, transcription factor recruiting activity, or cellular uptake signaling activity. Other preferred embodiments of the invention may include any combination the activities described herein.
Other preferred tools for genome editing for use in the context of this invention include zinc finger systems and TALE systems. One type of programmable DNA-binding domain is provided by artificial zinc-finger (ZF) technology, which involves arrays of ZF modules to target new DNA-binding sites in the genome. Each finger module in a ZF array targets three DNA bases. A customized array of individual zinc finger domains is assembled into a ZF protein (ZFP).
ZFPs can comprise a functional domain. The first synthetic zinc finger nucleases (ZFNs) were developed by fusing a ZF protein to the catalytic domain of the Type IIS restriction enzyme FokI. (Kim, Y. G. et al., 1994, Chimeric restriction endonuclease, Proc. Natl. Acad. Sci. U.S.A. 91, 883-887; Kim, Y. G. et al., 1996, Hybrid restriction enzymes: zinc finger fusions to Fok I cleavage domain. Proc. Natl. Acad. Sci. U.S.A. 93, 1156-1160). Increased cleavage specificity can be attained with decreased off target activity by use of paired ZFN heterodimers, each targeting different nucleotide sequences separated by a short spacer. (Doyon, Y. et al., 2011, Enhancing zinc-finger-nuclease activity with improved obligate heterodimeric architectures. Nat. Methods 8, 74-79). ZFPs can also be designed as transcription activators and repressors and have been used to target many genes in a wide variety of organisms. Exemplary methods of genome editing using ZFNs can be found for example in U.S. Pat. Nos. 6,534,261, 6,607,882, 6,746,838, 6,794,136, 6,824,978, 6,866,997, 6,933,113, 6,979,539, 7,013,219, 7,030,215, 7,220,719, 7,241,573, 7,241,574, 7,585,849, 7,595,376, 6,903,185, and 6,479,626, all of which are specifically incorporated by reference.
As disclosed herein editing can be made by way of meganucleases, which are endodeoxyribonucleases characterized by a large recognition site (double-stranded DNA sequences of 12 to 40 base pairs). Exemplary method for using meganucleases can be found in U.S. Pat. Nos. 8,163,514; 8,133,697; 8,021,867; 8,119,361; 8,119,381; 8,124,369; and 8,129,134, which are specifically incorporated by reference.
In certain example embodiments, the cargo may comprise a Cas protein and/or a guide molecule, or a CRISPR-Cas complex. In general, a CRISPR-Cas or CRISPR system as used herein and in other documents, such as WO 2014/093622 (PCT/US2013/074667), refers collectively to transcripts and other elements involved in the expression of or directing the activity of CRISPR-associated (“Cas”) genes, including sequences encoding a Cas gene, a tracr (trans-activating CRISPR) sequence (e.g., tracrRNA or an active partial tracrRNA), a tracr-mate sequence (encompassing a “direct repeat” and a tracrRNA-processed partial direct repeat in the context of an endogenous CRISPR system), a guide sequence (also referred to as a “spacer” in the context of an endogenous CRISPR system), or “RNA(s)” as that term is herein used (e.g., RNA(s) to guide Cas, such as Cas9, e.g., CRISPR RNA and transactivating (tracr) RNA or a single guide RNA (sgRNA) (chimeric RNA)) or other sequences and transcripts from a CRISPR locus. In general, a CRISPR system is characterized by elements that promote the formation of a CRISPR complex at the site of a target sequence (also referred to as a protospacer in the context of an endogenous CRISPR system). See, e.g, Shmakov et al. (2015) “Discovery and Functional Characterization of Diverse Class 2 CRISPR-Cas Systems”, Molecular Cell, DOI: dx.doi.org/10.1016/j.molcel.2015.10.008.
CRISPR-Cas systems can generally fall into two classes based on their architectures of their effector molecules, which are each further subdivided by type and subtype. The two class are Class 1 and Class 2. Class 1 CRISPR-Cas systems have effector modules composed of multiple Cas proteins, some of which form crRNA-binding complexes, while Class 2 CRISPR-Cas systems include a single, multi-domain crRNA-binding protein.
In some embodiments, the CRISPR-Cas system that can be used to modify a polynucleotide of the present invention described herein can be a Class 1 CRISPR-Cas system. In some embodiments, the CRISPR-Cas system that can be used to modify a polynucleotide of the present invention described herein can be a Class 2 CRISPR-Cas system.
In some embodiments, the CRISPR-Cas system that can be used to modify a polynucleotide of the present invention described herein can be a Class 1 CRISPR-Cas system. Class 1 CRISPR-Cas systems are divided into types I, II, and IV. Makarova et al. 2020. Nat. Rev. 18: 67-83., particularly as described in
The Class 1 systems typically use a multi-protein effector complex, which can, in some embodiments, include ancillary proteins, such as one or more proteins in a complex referred to as a CRISPR-associated complex for antiviral defense (Cascade), one or more adaptation proteins (e.g., Cas1, Cas2, RNA nuclease), and/or one or more accessory proteins (e.g., Cas 4, DNA nuclease), CRISPR associated Rossman fold (CARF) domain containing proteins, and/or RNA transcriptase.
The backbone of the Class 1 CRISPR-Cas system effector complexes can be formed by RNA recognition motif domain-containing protein(s) of the repeat-associated mysterious proteins (RAIVIPs) family subunits (e.g., Cas 5, Cas6, and/or Cas7). RAMP proteins are characterized by having one or more RNA recognition motif domains. In some embodiments, multiple copies of RAIVIPs can be present. In some embodiments, the Class I CRISPR-Cas system can include 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more Cas5, Cas6, and/or Cas 7 proteins. In some embodiments, the Cas6 protein is an RNAse, which can be responsible for pre-crRNA processing. When present in a Class 1 CRISPR-Cas system, Cas6 can be optionally physically associated with the effector complex.
Class 1 CRISPR-Cas system effector complexes can, in some embodiments, also include a large subunit. The large subunit can be composed of or include a Cas8 and/or Cas10 protein. See, e.g.,
Class 1 CRISPR-Cas system effector complexes can, in some embodiments, include a small subunit (for example, Cash 1). See, e.g.,
In some embodiments, the Class 1 CRISPR-Cas system can be a Type I CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-A CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-B CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-C CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-D CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-E CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-F1 CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-F2 CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-F3 CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a subtype I-G CRISPR-Cas system. In some embodiments, the Type I CRISPR-Cas system can be a CRISPR Cas variant, such as a Type I-A, I-B, I-E, I-F and I-U variants, which can include variants carried by transposons and plasmids, including versions of subtype I-F encoded by a large family of Tn7-like transposon and smaller groups of Tn7-like transposons that encode similarly degraded subtype I-B systems as previously described.
In some embodiments, the Class 1 CRISPR-Cas system can be a Type III CRISPR-Cas system. In some embodiments, the Type III CRISPR-Cas system can be a subtype III-A CRISPR-Cas system. In some embodiments, the Type III CRISPR-Cas system can be a subtype III-B CRISPR-Cas system. In some embodiments, the Type III CRISPR-Cas system can be a subtype III-C CRISPR-Cas system. In some embodiments, the Type III CRISPR-Cas system can be a subtype III-D CRISPR-Cas system. In some embodiments, the Type III CRISPR-Cas system can be a subtype III-E CRISPR-Cas system. In some embodiments, the Type III CRISPR-Cas system can be a subtype III-F CRISPR-Cas system.
In some embodiments, the Class 1 CRISPR-Cas system can be a Type IV CRISPR-Cas-system. In some embodiments, the Type IV CRISPR-Cas system can be a subtype IV-A CRISPR-Cas system. In some embodiments, the Type IV CRISPR-Cas system can be a subtype IV-B CRISPR-Cas system. In some embodiments, the Type IV CRISPR-Cas system can be a subtype IV-C CRISPR-Cas system.
The effector complex of a Class 1 CRISPR-Cas system can, in some embodiments, include a Cas3 protein that is optionally fused to a Cas2 protein, a Cas4, a Cas5, a Cash, a Cas7, a Cas8, a Cas10, a Cas11, or a combination thereof. In some embodiments, the effector complex of a Class 1 CRISPR-Cas system can have multiple copies, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or 14, of any one or more Cas proteins.
The compositions, systems, and methods described in greater detail elsewhere herein can be designed and adapted for use with Class 2 CRISPR-Cas systems. Thus, in some embodiments, the CRISPR-Cas system is a Class 2 CRISPR-Cas system. Class 2 systems are distinguished from Class 1 systems in that they have a single, large, multi-domain effector protein. In certain example embodiments, the Class 2 system can be a Type II, Type V, or Type VI system, which are described in Makarova et al. “Evolutionary classification of CRISPR-Cas systems: a burst of class 2 and derived variants” Nature Reviews Microbiology, 18:67-81 (February 2020), incorporated herein by reference. Each type of Class 2 system is further divided into subtypes. See Markova et al. 2020, particularly at Figure. 2. Class 2, Type II systems can be divided into 4 subtypes: II-A, II-B, II-C1, and II-C2. Class 2, Type V systems can be divided into 17 subtypes: V-A, V-B1, V-B2, V-C, V-D, V-E, V-F1, V-F1(V-U3), V-F2, V-F3, V-G, V-H, V-I, V-K (V-U5), V-U1, V-U2, and V-U4. Class 2, Type IV systems can be divided into 5 subtypes: VI-A, VI-B1, VI-B2, VI-C, and VI-D.
The distinguishing feature of these types is that their effector complexes consist of a single, large, multi-domain protein. Type V systems differ from Type II effectors (e.g., Cas9), which contain two nuclear domains that are each responsible for the cleavage of one strand of the target DNA, with the HNH nuclease inserted inside the Ruv-C like nuclease domain sequence. The Type V systems (e.g., Cas12) only contain a RuvC-like nuclease domain that cleaves both strands. Type VI (Cas13) are unrelated to the effectors of Type II and V systems and contain two HEPN domains and target RNA. Cas13 proteins also display collateral activity that is triggered by target recognition. Some Type V systems have also been found to possess this collateral activity with two single-stranded DNA in in vitro contexts.
In some embodiments, the Class 2 system is a Type II system. In some embodiments, the Type II CRISPR-Cas system is a II-A CRISPR-Cas system. In some embodiments, the Type II CRISPR-Cas system is a II-B CRISPR-Cas system. In some embodiments, the Type II CRISPR-Cas system is a II-C1 CRISPR-Cas system. In some embodiments, the Type II CRISPR-Cas system is a II-C2 CRISPR-Cas system. In some embodiments, the Type II system is a Cas9 system. In some embodiments, the Type II system includes a Cas9.
In some embodiments, the Class 2 system is a Type V system. In some embodiments, the Type V CRISPR-Cas system is a V-A CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-B 1 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-B2 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-C CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-D CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-E CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-F1 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-F1 (V-U3) CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-F2 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-F3 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-G CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-H CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-I CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-K (V-U5) CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-U1 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-U2 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system is a V-U4 CRISPR-Cas system. In some embodiments, the Type V CRISPR-Cas system includes a Cas12a (Cpf1), Cas12b (C2c1), Cas12c (C2c3), CasX, and/or Cas14.
In some embodiments the Class 2 system is a Type VI system. In some embodiments, the Type VI CRISPR-Cas system is a VI-A CRISPR-Cas system. In some embodiments, the Type VI CRISPR-Cas system is a VI-B1 CRISPR-Cas system. In some embodiments, the Type VI CRISPR-Cas system is a VI-B2 CRISPR-Cas system. In some embodiments, the Type VI CRISPR-Cas system is a VI-C CRISPR-Cas system. In some embodiments, the Type VI CRISPR-Cas system is a VI-D CRISPR-Cas system. In some embodiments, the Type VI CRISPR-Cas system includes a Cas13a (C2c2), Cas13b (Group 29/30), Cas13c, and/or Cas13d.
In some embodiments, the system is a Cas-based system that is capable of performing a specialized function or activity. For example, the Cas protein may be fused, operably coupled to, or otherwise associated with one or more functionals domains. In certain example embodiments, the Cas protein may be a catalytically dead Cas protein (“dCas”) and/or have nickase activity. A nickase is a Cas protein that cuts only one strand of a double stranded target. In such embodiments, the dCas or nickase provide a sequence specific targeting functionality that delivers the functional domain to or proximate a target sequence. Example functional domains that may be fused to, operably coupled to, or otherwise associated with a Cas protein can be or include, but are not limited to a nuclear localization signal (NLS) domain, a nuclear export signal (NES) domain, a translational activation domain, a transcriptional activation domain (e.g. VP64, p65, MyoD1, HSF1, RTA, and SETT/9), a translation initiation domain, a transcriptional repression domain (e.g., a KRAB domain, NuE domain, NcoR domain, and a SID domain such as a SID4X domain), a nuclease domain (e.g., FokI), a histone modification domain (e.g., a histone acetyltransferase), a light inducible/controllable domain, a chemically inducible/controllable domain, a transposase domain, a homologous recombination machinery domain, a recombinase domain, an integrase domain, and combinations thereof. Methods for generating catalytically dead Cas9 or a nickase Cas9 (WO 2014/204725, Ran et al. Cell. 2013 Sep. 12; 154(6):1380-1389), Cas12 (Liu et al. Nature Communications, 8, 2095 (2017), and Cas13 (WO 2019/005884, WO2019/060746) are known in the art and incorporated herein by reference.
In some embodiments, the functional domains can have one or more of the following activities: methylase activity, demethylase activity, translation activation activity, translation initiation activity, translation repression activity, transcription activation activity, transcription repression activity, transcription release factor activity, histone modification activity, nuclease activity, single-strand RNA cleavage activity, double-strand RNA cleavage activity, single-strand DNA cleavage activity, double-strand DNA cleavage activity, molecular switch activity, chemical inducibility, light inducibility, and nucleic acid binding activity. In some embodiments, the one or more functional domains may comprise epitope tags or reporters. Non-limiting examples of epitope tags include histidine (His) tags, V5 tags, FLAG tags, influenza hemagglutinin (HA) tags, Myc tags, VSV-G tags, and thioredoxin (Trx) tags. Examples of reporters include, but are not limited to, glutathione-S-transferase (GST), horseradish peroxidase (HRP), chloramphenicol acetyltransferase (CAT) beta-galactosidase, beta-glucuronidase, luciferase, green fluorescent protein (GFP), HcRed, DsRed, cyan fluorescent protein (CFP), yellow fluorescent protein (YFP), and auto-fluorescent proteins including blue fluorescent protein (BFP).
The one or more functional domain(s) may be positioned at, near, and/or in proximity to a terminus of the effector protein (e.g., a Cas protein). In embodiments having two or more functional domains, each of the two can be positioned at or near or in proximity to a terminus of the effector protein (e.g., a Cas protein). In some embodiments, such as those where the functional domain is operably coupled to the effector protein, the one or more functional domains can be tethered or linked via a suitable linker (including, but not limited to, GlySer linkers) to the effector protein (e.g., a Cas protein). When there is more than one functional domain, the functional domains can be same or different. In some embodiments, all the functional domains are the same. In some embodiments, all of the functional domains are different from each other. In some embodiments, at least two of the functional domains are different from each other. In some embodiments, at least two of the functional domains are the same as each other.
Other suitable functional domains can be found, for example, in International Application Publication No. WO 2019/018423.
Split CRISPR-Cas systems
In some embodiments, the CRISPR-Cas system is a split CRISPR-Cas system. See e.g., Zetche et al., 2015. Nat. Biotechnol. 33(2): 139-142 and WO 2019/018423, the compositions and techniques of which can be used in and/or adapted for use with the present invention. Split CRISPR-Cas proteins are set forth herein and in documents incorporated herein by reference in further detail herein. In certain embodiments, each part of a split CRISPR protein are attached to a member of a specific binding pair, and when bound with each other, the members of the specific binding pair maintain the parts of the CRISPR protein in proximity. In certain embodiments, each part of a split CRISPR protein is associated with an inducible binding pair. An inducible binding pair is one which is capable of being switched “on” or “off” by a protein or small molecule that binds to both members of the inducible binding pair. In some embodiments, CRISPR proteins may preferably split between domains, leaving domains intact. In particular embodiments, said Cas split domains (e.g., RuvC and HNH domains in the case of Cas9) can be simultaneously or sequentially introduced into the cell such that said split Cas domain(s) process the target nucleic acid sequence in the algae cell. The reduced size of the split Cas compared to the wild type Cas allows other methods of delivery of the systems to the cells, such as the use of cell penetrating peptides as described herein.
In some embodiments, a polynucleotide of the present invention described elsewhere herein can be modified using a base editing system. In some embodiments, a Cas protein is connected or fused to a nucleotide deaminase. Thus, in some embodiments the Cas-based system can be a base editing system. As used herein “base editing” refers generally to the process of polynucleotide modification via a CRISPR-Cas-based or Cas-based system that does not include excising nucleotides to make the modification. Base editing can convert base pairs at precise locations without generating excess undesired editing byproducts that can be made using traditional CRISPR-Cas systems.
In certain example embodiments, the nucleotide deaminase may be a DNA base editor used in combination with a DNA binding Cas protein such as, but not limited to, Class 2 Type II and Type V systems. Two classes of DNA base editors are generally known: cytosine base editors (CBEs) and adenine base editors (ABEs). CBEs convert a C⋅G base pair into a T⋅A base pair (Komor et al. 2016. Nature. 533:420-424; Nishida et al. 2016. Science. 353; and Li et al. Nat. Biotech. 36:324-327) and ABEs convert an A⋅T base pair to a G⋅C base pair. Collectively, CBEs and ABEs can mediate all four possible transition mutations (C to T, A to G, T to C, and G to A). Rees and Liu. 2018.Nat. Rev. Genet. 19(12): 770-788, particularly at
Other Example Type V base editing systems are described in WO 2018/213708, WO 2018/213726, PCT/US2018/067207, PCT/US2018/067225, and PCT/US2018/067307 which are incorporated by referenced herein.
In certain example embodiments, the base editing system may be a RNA base editing system. As with DNA base editors, a nucleotide deaminase capable of converting nucleotide bases may be fused to a Cas protein. However, in these embodiments, the Cas protein will need to be capable of binding RNA. Example RNA binding Cas proteins include, but are not limited to, RNA-binding Cas9s such as Francisella novicida Cas9 (“FnCas9”), and Class 2 Type VI Cas systems. The nucleotide deaminase may be a cytidine deaminase or an adenosine deaminase, or an adenosine deaminase engineered to have cytidine deaminase activity. In certain example embodiments, the RNA based editor may be used to delete or introduce a post-translation modification site in the expressed mRNA. In contrast to DNA base editors, whose edits are permanent in the modified cell, RNA base editors can provide edits where finer temporal control may be needed, for example in modulating a particular immune response. Example Type VI RNA-base editing systems are described in Cox et al. 2017. Science 358: 1019-1027, WO 2019/005884, WO 2019/005886, WO 2019/071048, PCT/US20018/05179, PCT/US2018/067207, which are incorporated herein by reference. An example FnCas9 system that may be adapted for RNA base editing purposes is described in WO 2016/106236, which is incorporated herein by reference.
An example method for delivery of base-editing systems, including use of a split-intein approach to divide CBE and ABE into reconstituble halves, is described in Levy et al. Nature Biomedical Engineering doi.org/10.1038/s41441-019-0505-5 (2019), which is incorporated herein by reference.
In some embodiments, a polynucleotide of the present invention described elsewhere herein can be modified using a prime editing system See e.g. Anzalone et al. 2019. Nature. 576: 149-157. Like base editing systems, prime editing systems can be capable of targeted modification of a polynucleotide without generating double stranded breaks and does not require donor templates. Further prime editing systems can be capable of all 12 possible combination swaps. Prime editing can operate via a “search-and-replace” methodology and can mediate targeted insertions, deletions, all 12 possible base-to-base conversion, and combinations thereof. Generally, a prime editing system, as exemplified by PE1, PE2, and PE3 (Id.), can include a reverse transcriptase fused or otherwise coupled or associated with an RNA-programmable nickase, and a prime-editing extended guide RNA (pegRNA) to facility direct copying of genetic information from the extension on the pegRNA into the target polynucleotide. Embodiments that can be used with the present invention include these and variants thereof. Prime editing can have the advantage of lower off-target activity than traditional CRIPSR-Cas systems along with few byproducts and greater or similar efficiency as compared to traditional CRISPR-Cas systems.
In some embodiments, the prime editing guide molecule can specify both the target polynucleotide information (e.g. sequence) and contain a new polynucleotide cargo that replaces target polynucleotides. To initiate transfer from the guide molecule to the target polynucleotide, the PE system can nick the target polynucleotide at a target side to expose a 3′hydroxyl group, which can prime reverse transcription of an edit-encoding extension region of the guide molecule (e.g. a prime editing guide molecule or peg guide molecule) directly into the target site in the target polynucleotide. See e.g. Anzalone et al. 2019. Nature. 576: 149-157, particularly at
In some embodiments, a prime editing system can be composed of a Cas polypeptide having nickase activity, a reverse transcriptase, and a guide molecule. The Cas polypeptide can lack nuclease activity. The guide molecule can include a target binding sequence as well as a primer binding sequence and a template containing the edited polynucleotide sequence. The guide molecule, Cas polypeptide, and/or reverse transcriptase can be coupled together or otherwise associate with each other to form an effector complex and edit a target sequence. In some embodiments, the Cas polypeptide is a Class 2, Type V Cas polypeptide. In some embodiments, the Cas polypeptide is a Cas9 polypeptide (e.g. is a Cas9 nickase). In some embodiments, the Cas polypeptide is fused to the reverse transcriptase. In some embodiments, the Cas polypeptide is linked to the reverse transcriptase.
In some embodiments, the prime editing system can be a PE1 system or variant thereof, a PE2 system or variant thereof, or a PE3 (e.g. PE3, PE3b) system. See e.g., Anzalone et al. 2019. Nature. 576: 149-157, particularly at pgs. 2-3,
The peg guide molecule can be about 10 to about 200 or more nucleotides in length, such as 10 to/or 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, or 200 or more nucleotides in length. Optimization of the peg guide molecule can be accomplished as described in Anzalone et al. 2019. Nature. 576: 149-157, particularly at pg. 3,
In some embodiments, a polynucleotide of the present invention described elsewhere herein can be modified using a CRISPR Associated Transposase (“CAST”) system. CAST system can include a Cas protein that is catalytically inactive, or engineered to be catalytically active, and further comprises a transposase (or subunits thereof) that catalyze RNA-guided DNA transposition. Such systems are able to insert DNA sequences at a target site in a DNA molecule without relying on host cell repair machinery. CAST systems can be Class1 or Class 2 CAST systems. An example Class 1 system is described in Klompe et al. Nature, doi:10.1038/s41586-019-1323, which is in incorporated herein by reference. An example Class 2 system is described in Strecker et al. Science. 10/1126/science. aax9181 (2019), and PCT/US2019/066835 which are incorporated herein by reference.
The CRISPR-Cas or Cas-Based system described herein can, in some embodiments, include one or more guide molecules. The terms guide molecule, guide sequence and guide polynucleotide, refer to polynucleotides capable of guiding Cas to a target genomic locus and are used interchangeably as in foregoing cited documents such as WO 2014/093622 (PCT/US2013/074667). In general, a guide sequence is any polynucleotide sequence having sufficient complementarity with a target polynucleotide sequence to hybridize with the target sequence and direct sequence-specific binding of a CRISPR complex to the target sequence. The guide molecule can be a polynucleotide.
The ability of a guide sequence (within a nucleic acid-targeting guide RNA) to direct sequence-specific binding of a nucleic acid-targeting complex to a target nucleic acid sequence may be assessed by any suitable assay. For example, the components of a nucleic acid-targeting CRISPR system sufficient to form a nucleic acid-targeting complex, including the guide sequence to be tested, may be provided to a host cell having the corresponding target nucleic acid sequence, such as by transfection with vectors encoding the components of the nucleic acid-targeting complex, followed by an assessment of preferential targeting (e.g., cleavage) within the target nucleic acid sequence, such as by Surveyor assay (Qui et al. 2004. BioTechniques. 36(4)702-707). Similarly, cleavage of a target nucleic acid sequence may be evaluated in a test tube by providing the target nucleic acid sequence, components of a nucleic acid-targeting complex, including the guide sequence to be tested and a control guide sequence different from the test guide sequence, and comparing binding or rate of cleavage at the target sequence between the test and control guide sequence reactions. Other assays are possible and will occur to those skilled in the art.
In some embodiments, the guide molecule is an RNA. The guide molecule(s) (also referred to interchangeably herein as guide polynucleotide and guide sequence) that are included in the CRISPR-Cas or Cas based system can be any polynucleotide sequence having sufficient complementarity with a target nucleic acid sequence to hybridize with the target nucleic acid sequence and direct sequence-specific binding of a nucleic acid-targeting complex to the target nucleic acid sequence. In some embodiments, the degree of complementarity, when optimally aligned using a suitable alignment algorithm, can be about or more than about 50%, 60%, 75%, 80%, 85%, 90%, 95%, 97.5%, 99%, or more. Optimal alignment may be determined with the use of any suitable algorithm for aligning sequences, non-limiting examples of which include the Smith-Waterman algorithm, the Needleman-Wunsch algorithm, algorithms based on the Burrows-Wheeler Transform (e.g., the Burrows Wheeler Aligner), ClustalW, Clustal X, BLAT, Novoalign (Novocraft Technologies; available at www.novocraft.com), ELAND (Illumina, San Diego, Calif.), SOAP (available at soap.genomics.org.cn), and Maq (available at maq.sourceforge.net).
In some embodiments, the composition for engineering cells comprise a template, e.g., a recombination template. A template may be a component of another vector as described herein, contained in a separate vector, or provided as a separate polynucleotide. In some embodiments, a recombination template is designed to serve as a template in homologous recombination, such as within or near a target sequence nicked or cleaved by a nucleic acid-targeting effector protein as a part of a nucleic acid-targeting complex.
In an embodiment, the template nucleic acid alters the sequence of the target position. In an embodiment, the template nucleic acid results in the incorporation of a modified, or non-naturally occurring base into the target nucleic acid.
The template sequence may undergo a breakage mediated or catalyzed recombination with the target sequence. In an embodiment, the template nucleic acid may include sequence that corresponds to a site on the target sequence that is cleaved by a Cas protein mediated cleavage event. In an embodiment, the template nucleic acid may include sequence that corresponds to both, a first site on the target sequence that is cleaved in a first Cas protein mediated event, and a second site on the target sequence that is cleaved in a second Cas protein mediated event.
In certain embodiments, the template nucleic acid can include sequence which results in an alteration in the coding sequence of a translated sequence, e.g., one which results in the substitution of one amino acid for another in a protein product, e.g., transforming a mutant allele into a wild type allele, transforming a wild type allele into a mutant allele, and/or introducing a stop codon, insertion of an amino acid residue, deletion of an amino acid residue, or a nonsense mutation. In certain embodiments, the template nucleic acid can include sequence which results in an alteration in a non-coding sequence, e.g., an alteration in an exon or in a 5′ or 3′ non-translated or non-transcribed region. Such alterations include an alteration in a control element, e.g., a promoter, enhancer, and an alteration in a cis-acting or trans-acting control element.
A template nucleic acid having homology with a target position in a target gene may be used to alter the structure of a target sequence. The template sequence may be used to alter an unwanted structure, e.g., an unwanted or mutant nucleotide. The template nucleic acid may include sequence which, when integrated, results in: decreasing the activity of a positive control element; increasing the activity of a positive control element; decreasing the activity of a negative control element; increasing the activity of a negative control element; decreasing the expression of a gene; increasing the expression of a gene; increasing resistance to a disorder or disease; increasing resistance to viral entry; correcting a mutation or altering an unwanted amino acid residue conferring, increasing, abolishing or decreasing a biological property of a gene product, e.g., increasing the enzymatic activity of an enzyme, or increasing the ability of a gene product to interact with another molecule.
The template nucleic acid may include sequence which results in: a change in sequence of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 or more nucleotides of the target sequence.
A template polynucleotide may be of any suitable length, such as about or more than about 10, 15, 20, 25, 50, 75, 100, 150, 200, 500, 1000, or more nucleotides in length. In an embodiment, the template nucleic acid may be 20+/−10, 30+/−10, 40+/−10, 50+/−10, 60+/−10, 70+/−10, 80+/−10, 90+/−10, 100+/−10, 1 10+/−10, 120+/−10, 130+/−10, 140+/−10, 150+/−10, 160+/−10, 170+/−10, 1 80+/−10, 190+/−10, 200+/−10, 210+/−10, of 220+/−10 nucleotides in length. In an embodiment, the template nucleic acid may be 30+/−20, 40+/−20, 50+/−20, 60+/−20, 70+/−20, 80+/−20, 90+/−20, 100+/−20, 1 10+/−20, 120+/−20, 130+/−20, 140+/−20, I 50+/−20, 160+/−20, 170+/−20, 180+/−20, 190+/−20, 200+/−20, 210+/−20, of 220+/−20 nucleotides in length. In an embodiment, the template nucleic acid is 10 to 1,000, 20 to 900, 30 to 800, 40 to 700, 50 to 600, 50 to 500, 50 to 400, 50 to 300, 50 to 200, or 50 to 100 nucleotides in length.
In some embodiments, the template polynucleotide is complementary to a portion of a polynucleotide comprising the target sequence. When optimally aligned, a template polynucleotide might overlap with one or more nucleotides of a target sequences (e.g. about or more than about 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 100 or more nucleotides). In some embodiments, when a template sequence and a polynucleotide comprising a target sequence are optimally aligned, the nearest nucleotide of the template polynucleotide is within about 1, 5, 10, 15, 20, 25, 50, 75, 100, 200, 300, 400, 500, 1000, 5000, 10000, or more nucleotides from the target sequence.
The exogenous polynucleotide template comprises a sequence to be integrated (e.g., a mutated gene). The sequence for integration may be a sequence endogenous or exogenous to the cell. Examples of a sequence to be integrated include polynucleotides encoding a protein or a non-coding RNA (e.g., a microRNA). Thus, the sequence for integration may be operably linked to an appropriate control sequence or sequences. Alternatively, the sequence to be integrated may provide a regulatory function.
An upstream or downstream sequence may comprise from about 20 bp to about 2500 bp, for example, about 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, 2300, 2400, or 2500 bp. In some methods, the exemplary upstream or downstream sequence have about 200 bp to about 2000 bp, about 600 bp to about 1000 bp, or more particularly about 700 bp to about 1000.
An upstream or downstream sequence may comprise from about 20 bp to about 2500 bp, for example, about 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, 2300, 2400, or 2500 bp. In some methods, the exemplary upstream or downstream sequence have about 200 bp to about 2000 bp, about 600 bp to about 1000 bp, or more particularly about 700 bp to about 1000
In certain embodiments, one or both homology arms may be shortened to avoid including certain sequence repeat elements. For example, a 5′ homology arm may be shortened to avoid a sequence repeat element. In other embodiments, a 3′ homology arm may be shortened to avoid a sequence repeat element. In some embodiments, both the 5′ and the 3′ homology arms may be shortened to avoid including certain sequence repeat elements.
In some methods, the exogenous polynucleotide template may further comprise a marker. Such a marker may make it easy to screen for targeted integrations. Examples of suitable markers include restriction sites, fluorescent proteins, or selectable markers. The exogenous polynucleotide template of the disclosure can be constructed using recombinant techniques (see, for example, Sambrook et al., 2001 and Ausubel et al., 1996).
In certain embodiments, a template nucleic acid for correcting a mutation may designed for use as a single-stranded oligonucleotide. When using a single-stranded oligonucleotide, 5′ and 3′ homology arms may range up to about 200 base pairs (bp) in length, e.g., at least 25, 50, 75, 100, 125, 150, 175, or 200 by in length.
Suzuki et al. describe in vivo genome editing via CRISPR/Cas9 mediated homology-independent targeted integration (2016, Nature 540:144-149).
In some embodiments, the nucleic acids and/or proteins may comprise ribonucleoproteins (RNP). In specific embodiments, the RNPs may comprise a CRISPR system. In specific embodiments, the CRISPR system may comprise a CRISPR effector protein and one or more guide sequences specific for one or more target nucleic acids. RNPs have the advantage that they lead to rapid editing effects even more so than the RNA method because this process avoids the need for transcription. An important advantage is that RNP delivery is transient, reducing off-target effects and toxicity issues. Efficient genome editing in different cell types has been observed by Kim et al. (2014, Genome Res. 24(6):1012-9), Paix et al. (2015, Genetics 204(1):47.
The polypeptides described herein may be encoded by a nucleic acid sequence, which may be comprised in a vector. For example, a vector encoding the non-naturally occurring polypeptide that self-assembles into an export compartment may be delivered to a target cell or population of cells to facilitate export of a target biomolecule from that cell or population of cells.
Certain vectors are capable of directing the expression of genes to which they are operatively-linked. Such vectors are referred to herein as “expression vectors.” Common expression vectors of utility in recombinant DNA techniques are often in the form of plasmids. Recombinant expression vectors can comprise a nucleic acid of the invention in a form suitable for expression of the nucleic acid in a host cell, which means that the recombinant expression vectors include one or more regulatory elements, which may be selected on the basis of the host cells to be used for expression, that is operatively-linked to the nucleic acid sequence to be expressed. Within a recombinant expression vector, “operably linked” is intended to mean that the nucleotide sequence of interest is linked to the regulatory element(s) in a manner that allows for expression of the nucleotide sequence (e.g. in an in vitro transcription/translation system or in a host cell when the vector is introduced into the host cell). With regards to recombination and cloning methods, mention is made of U.S. patent application Ser. No. 10/815,730, published Sep. 2, 2004 as US 2004-0171156 A1, the contents of which are herein incorporated by reference in their entirety.
In some embodiments, the population of cells may include, but is not necessarily limited to, yeast, insect cells, or mammalian cells, as previously described. In specific embodiments, the population of cells are mammalian neurons and the cells are activated to release extracellular vesicles.
In some embodiments, the cells may be activated with KCl treatment. In some embodiments, the extracellular vesicle fraction may be purified by gradient sedimentation. In some embodiments, the purified extracellular vesicles may be treated with RNase.
As previously described, the GAG-like protein may be selected from the group consisting of ARC, ZCC18, ZCH12, PNM8B, PNM8B, PNM6A, PMA6F, PMA6E, PNMA2, PNM8A, PNMA3, PNMA5, PNMA1, MOAP1, and CCDC8. In specific embodiments, the GAG-like protein is ARC.
The nucleic acids and/or proteins may comprise one or more sequences encoding a CRISPR effector protein and one or more guide sequences specific for one or more target nucleic acids, as previously described.
In certain embodiments, compositions are envisioned comprising any of the polypeptides, nucleic acid sequences, and vectors described herein. Specific embodiments comprise one or more suitable pharmaceutical carriers and/or excipients.
A “pharmaceutical composition” refers to a composition that usually contains an excipient, such as a pharmaceutically acceptable carrier that is conventional in the art and that is suitable for administration to cells or to a subject.
The pharmaceutical compositions (or “medicaments”) of the invention are prepared in a manner known to those skilled in the art, for example, by means of conventional dissolving, lyophilizing, mixing, granulating or confectioning processes. Methods well known in the art for making formulations are found, for example, in Remington: The Science and Practice of Pharmacy, 20th ed., ed. A. R. Gennaro, 2000, Lippincott Williams & Wilkins, Philadelphia, and Encyclopedia of Pharmaceutical Technology, eds. J. Swarbrick and J. C. Boylan, 1988-1999, Marcel Dekker, New York.
The term “pharmaceutically acceptable” as used throughout this specification is consistent with the art and means compatible with the other ingredients of a pharmaceutical composition and not deleterious to the recipient thereof.
The agents disclosed herein may be used in a pharmaceutical composition when combined with a pharmaceutically acceptable carrier. Such compositions comprise a therapeutically effective amount of the agent and a pharmaceutically acceptable carrier. Such a composition may also further comprise (in addition to an agent and a carrier) diluents, fillers, salts, buffers, stabilizers, solubilizers, and other materials well known in the art. Compositions comprising the agent can be administered in the form of salts provided the salts are pharmaceutically acceptable. Salts may be prepared using standard procedures known to those skilled in the art of synthetic organic chemistry.
As used herein, “carrier” or “excipient” includes any and all solvents, diluents, buffers (such as, e.g., neutral buffered saline or phosphate buffered saline), solubilizers, colloids, dispersion media, vehicles, fillers, chelating agents (such as, e.g., EDTA or glutathione), amino acids (such as, e.g., glycine), proteins, disintegrants, binders, lubricants, wetting agents, emulsifiers, sweeteners, colorants, flavourings, aromatisers, thickeners, agents for achieving a depot effect, coatings, antifungal agents, preservatives, stabilisers, antioxidants, tonicity controlling agents, absorption delaying agents, and the like. The use of such media and agents for pharmaceutical active components is well known in the art. Such materials should be non-toxic and should not interfere with the activity of the cells or active components.
The precise nature of the carrier or excipient or other material will depend on the route of administration. For example, the composition may be in the form of a parenterally acceptable aqueous solution, which is pyrogen-free and has suitable pH, isotonicity and stability. For general principles in medicinal formulation, the reader is referred to Cell Therapy: Stem Cell Transplantation, Gene Therapy, and Cellular Immunotherapy, by G. Morstyn & W. Sheridan eds., Cambridge University Press, 1996; and Hematopoietic Stem Cell Therapy, E. D. Ball, J. Lister & P. Law, Churchill Livingstone, 2000.
Other excipients suitable for pharmaceutical compositions intended for delivery of antibodies to the respiratory tract mucosa may be a) carbohydrates, e.g., monosaccharides such as fructose, galactose, glucose. D-mannose, sorbiose, and the like; disaccharides, such as lactose, trehalose, cellobiose, and the like; cyclodextrins, such as 2-hydroxypropyl-β-cyclodextrin; and polysaccharides, such as raffinose, maltodextrins, dextrans, and the like; b) amino acids, such as glycine, arginine, aspartic acid, glutamic acid, cysteine, lysine and the like; c) organic salts prepared from organic acids and bases, such as sodium citrate, sodium ascorbate, magnesium gluconate, sodium gluconate, tromethamine hydrochloride, and the like: d) peptides and proteins, such as aspartame, human serum albumin, gelatin, and the like; e) alditols, such mannitol, xylitol, and the like, and f) polycationic polymers, such as chitosan or a chitosan salt or derivative.
The term “pharmaceutically acceptable salts” refers to salts prepared from pharmaceutically acceptable non-toxic bases or acids including inorganic or organic bases and inorganic or organic acids. Salts derived from inorganic bases include aluminum, ammonium, calcium, copper, ferric, ferrous, lithium, magnesium, manganic salts, manganous, potassium, sodium, zinc, and the like. Particularly preferred are the ammonium, calcium, magnesium, potassium, and sodium salts. Salts derived from pharmaceutically acceptable organic non-toxic bases include salts of primary, secondary, and tertiary amines, substituted amines including naturally occurring substituted amines, cyclic amines, and basic ion exchange resins, such as arginine, betaine, caffeine, choline, N,N′-dibenzylethylenediamine, diethylamine, 2-diethylaminoethanol, 2-dimethylaminoethanol, ethanolamine, ethylenediamine, N-ethyl-morpholine, N-ethylpiperidine, glucamine, glucosamine, histidine, hydrabamine, isopropylamine, lysine, methylglucamine, morpholine, piperazine, piperidine, polyamine resins, procaine, purines, theobromine, triethylamine, trimethylamine, tripropylamine, tromethamine, and the like. The term “pharmaceutically acceptable salt” further includes all acceptable salts such as acetate, lactobionate, benzenesulfonate, laurate, benzoate, malate, bicarbonate, maleate, bisulfate, mandelate, bitartrate, mesylate, borate, methylbromide, bromide, methylnitrate, calcium edetate, methylsulfate, camsylate, mucate, carbonate, napsylate, chloride, nitrate, clavulanate, N-methylglucamine, citrate, ammonium salt, dihydrochloride, oleate, edetate, oxalate, edisylate, pamoate (embonate), estolate, palmitate, esylate, pantothenate, fumarate, phosphate/diphosphate, gluceptate, polygalacturonate, gluconate, salicylate, glutamate, stearate, glycollylarsanilate, sulfate, hexylresorcinate, subacetate, hydrabamine, succinate, hydrobromide, tannate, hydrochloride, tartrate, hydroxynaphthoate, teoclate, iodide, tosylate, isothionate, triethiodide, lactate, panoate, valerate, and the like which can be used as a dosage form for modifying the solubility or hydrolysis characteristics or can be used in sustained release or pro-drug formulations. It will be understood that, as used herein, references to specific agents (e.g., neuromedin U receptor agonists or antagonists), also include the pharmaceutically acceptable salts thereof.
The pharmaceutical composition can be applied parenterally, rectally, orally or topically. Preferably, the pharmaceutical composition may be used for intravenous, intramuscular, subcutaneous, peritoneal, peridural, rectal, nasal, pulmonary, mucosal, or oral application. In a preferred embodiment, the pharmaceutical composition according to the invention is intended to be used as an infusion. The skilled person will understand that compositions which are to be administered orally or topically will usually not comprise cells, although they may be envisioned for oral compositions to also comprise cells, for example when gastro-intestinal tract indications are treated. Each of the cells or active components (e.g., immunomodulants) as discussed herein may be administered by the same route or may be administered by a different route. By means of example, and without limitation, cells may be administered parenterally and other active components may be administered orally.
Liquid pharmaceutical compositions may generally include a liquid carrier such as water or a pharmaceutically acceptable aqueous solution. For example, physiological saline solution, tissue or cell culture media, dextrose or other saccharide solution or glycols such as ethylene glycol, propylene glycol or polyethylene glycol may be included.
The composition may include one or more cell protective molecules, cell regenerative molecules, growth factors, anti-apoptotic factors or factors that regulate gene expression in the cells. Such substances may render the cells independent of their environment.
Such pharmaceutical compositions may contain further components ensuring the viability of the cells therein. For example, the compositions may comprise a suitable buffer system (e.g., phosphate or carbonate buffer system) to achieve desirable pH, more usually near neutral pH, and may comprise sufficient salt to ensure isoosmotic conditions for the cells to prevent osmotic stress. For example, suitable solutions for these purposes may be phosphate-buffered saline (PBS), sodium chloride solution, Ringer's Injection or Lactated Ringer's Injection, as known in the art. Further, the composition may comprise a carrier protein, e.g., albumin (e.g., bovine or human albumin), which may increase the viability of the cells.
Further suitable pharmaceutically acceptable carriers or additives are well known to those skilled in the art and for instance may be selected from proteins such as collagen or gelatine, carbohydrates such as starch, polysaccharides, sugars (dextrose, glucose and sucrose), cellulose derivatives like sodium or calcium carboxymethylcellulose, hydroxypropyl cellulose or hydroxypropylmethyl cellulose, pregelatinized starches, pectin agar, carrageenan, clays, hydrophilic gums (acacia gum, guar gum, arabic gum and xanthan gum), alginic acid, alginates, hyaluronic acid, polyglycolic and polylactic acid, dextran, pectins, synthetic polymers such as water-soluble acrylic polymer or polyvinylpyrrolidone, proteoglycans, calcium phosphate and the like.
In certain embodiments, a pharmaceutical cell preparation as taught herein may be administered in a form of liquid composition. In embodiments, the cells or pharmaceutical composition comprising such can be administered systemically, topically, within an organ or at a site of organ dysfunction or lesion.
Preferably, the pharmaceutical compositions may comprise a therapeutically effective amount of the specified immune cells and/or other active components (e.g., immunomodulants). The term “therapeutically effective amount” refers to an amount which can elicit a biological or medicinal response in a tissue, system, animal or human that is being sought by a researcher, veterinarian, medical doctor or other clinician, and in particular can prevent or alleviate one or more of the local or systemic symptoms or features of a disease or condition being treated.
Examples of solvents are e.g. water, alcohols, vegetable or marine oils (e.g. edible oils like almond oil, castor oil, cacao butter, coconut oil, corn oil, cottonseed oil, linseed oil, olive oil, palm oil, peanut oil, poppy seed oil, rapeseed oil, sesame oil, soybean oil, sunflower oil, and tea seed oil), mineral oils, fatty oils, liquid paraffin, polyethylene glycols, propylene glycols, glycerol, liquid polyalkylsiloxanes, and mixtures thereof.
Examples of buffering agents are e.g. citric acid, acetic acid, tartaric acid, lactic acid, hydrogenphosphoric acid, diethyl amine etc. Suitable examples of preservatives for use in compositions are parabens, such as methyl, ethyl, propyl p-hydroxybenzoate, butylparaben, isobutylparaben, isopropylparaben, potassium sorbate, sorbic acid, benzoic acid, methyl benzoate, phenoxyethanol, bronopol, bronidox, MDM hydantoin, iodopropynyl butylcarbamate, EDTA, benzalconium chloride, and benzylalcohol, or mixtures of preservatives.
Examples of humectants are glycerin, propylene glycol, sorbitol, lactic acid, urea, and mixtures thereof.
Examples of antioxidants are butylated hydroxy anisole (BHA), ascorbic acid and derivatives thereof, tocopherol and derivatives thereof, cysteine, and mixtures thereof.
Examples of emulsifying agents are naturally occurring gums, e.g. gum acacia or gum tragacanth; naturally occurring phosphatides, e.g. soybean lecithin, sorbitan monooleate derivatives: wool fats; wool alcohols; sorbitan esters; monoglycerides; fatty alcohols; fatty acid esters (e.g. triglycerides of fatty acids); and mixtures thereof.
Examples of suspending agents are e.g. celluloses and cellulose derivatives such as, e.g., carboxymethyl cellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, carrageenan, acacia gum, arabic gum, tragacanth, and mixtures thereof.
Examples of gel bases, viscosity-increasing agents or components which are able to take up exudate from a wound are: liquid paraffin, polyethylene, fatty oils, colloidal silica or aluminum, zinc soaps, glycerol, propylene glycol, tragacanth, carboxyvinyl polymers, magnesium-aluminum silicates, Carbopol®, hydrophilic polymers such as, e.g. starch or cellulose derivatives such as, e.g., carboxymethylcellulose, hydroxyethylcellulose and other cellulose derivatives, water-swellable hydrocolloids, carrageenans, hyaluronates (e.g. hyaluronate gel optionally containing sodium chloride), and alginates including propylene glycol alginate.
Examples of ointment bases are e.g. beeswax, paraffin, cetanol, cetyl palmitate, vegetable oils, sorbitan esters of fatty acids (Span), polyethylene glycols, and condensation products between sorbitan esters of fatty acids and ethylene oxide, e.g. polyoxyethylene sorbitan monooleate (Tween).
Examples of hydrophobic or water-emulsifying ointment bases are paraffins, vegetable oils, animal fats, synthetic glycerides, waxes, lanolin, and liquid polyalkylsiloxanes. Examples of hydrophilic ointment bases are solid macrogols (polyethylene glycols). Other examples of ointment bases are triethanolamine soaps, sulphated fatty alcohol and polysorbates.
Examples of other excipients are polymers such as carmelose, sodium carmelose, hydroxypropylmethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, pectin, xanthan gum, locust bean gum, acacia gum, gelatin, carbomer, emulsifiers like vitamin E, glyceryl stearates, cetanyl glucoside, collagen, carrageenan, hyaluronates and alginates and chitosans.
In specific embodiments, the pharmaceutical compositions comprise nucleic acids and/or proteins in a non-naturally occurring capsid as described herein.
Methods of Delivering Nucleic Acids and/or Protein to a Cell or Between Populations of Cells
In certain example embodiments, the invention further includes a method of delivering nucleic acids and/or proteins to cells by expressing any of the self-assembling polypeptides described herein in a population of culture cells comprising the nucleic acids or proteins to be delivered, such that the nucleic acids and/or proteins are captured and packaged within export compartments by the self-assembling polypeptide. Advantageously, the export compartment exported by the population of cultured cells may be isolated and delivered to a target cell or cell population for uptake by the target cell or cell population.
In certain example embodiments, the invention provides a method of delivering nucleic acids and/or proteins between populations of cells. The method may comprise delivering any of the nucleic acids or vectors described herein to a first population of donor cells cultured in the presence of one or more recipient cell populations. The self-assembling polypeptide may be expressed such that the target nucleic acids and/or proteins from the donor cells are packaged in export compartments and are delivered to the one or more recipient cell populations by exporting of the export compartments from the donor cells to the one or more cell populations.
In certain example embodiments, the invention further includes a method of transferring or delivering nucleic acids and/or proteins to a cell comprising introducing to one or more cells, non-naturally occurring capsids obtained by any of the methods described herein.
There are a variety of techniques available for introducing nucleic acids into viable cells. The techniques vary depending upon whether the nucleic acid is transferred into cultured cells in vitro, or in vivo in the cells of the intended host. Techniques suitable for the transfer of nucleic acid into mammalian cells in vitro include the use of liposomes, electroporation, microinjection, cell fusion, DEAE-dextran, the calcium phosphate precipitation method, etc. The currently preferred in vivo gene transfer techniques include transfection with viral (typically retroviral) vectors and viral coat protein-liposome mediated transfection.
Electroporation has been used in both in vitro and in vivo procedures to introduce foreign material into living cells. With in vitro applications, a sample of live cells is first mixed with the agent of interest and placed between electrodes such as parallel plates. Then, the electrodes apply an electrical field to the cell/implant mixture. Examples of systems that perform in vitro electroporation include the Electro Cell Manipulator ECM600 product, and the Electro Square Porator T820, both made by the BTX Division of Genetronics, Inc (see U.S. Pat. No. 5,869,326).
The known electroporation techniques (both in vitro and in vivo) function by applying a brief high voltage pulse to electrodes positioned around the treatment region. The electric field generated between the electrodes causes the cell membranes to temporarily become porous, whereupon molecules of the agent of interest enter the cells. In known electroporation applications, this electric field comprises a single square wave pulse on the order of 1000 V/cm, of about 100 .mu.s duration. Such a pulse may be generated, for example, in known applications of the Electro Square Porator T820.
Preferably, the electric field has a strength of from about 1 V/cm to about 10 kV/cm under in vitro conditions. Thus, the electric field may have a strength of 1 V/cm, 2 V/cm, 3 V/cm, 4 V/cm, 5 V/cm, 6 V/cm, 7 V/cm, 8 V/cm, 9 V/cm, 10 V/cm, 20 V/cm, 50 V/cm, 100 V/cm, 200 V/cm, 300 V/cm, 400 V/cm, 500 V/cm, 600 V/cm, 700 V/cm, 800 V/cm, 900 V/cm, 1 kV/cm, 2 kV/cm, 5 kV/cm, 10 kV/cm, 20 kV/cm, 50 kV/cm or more. More preferably from about 0.5 kV/cm to about 4.0 kV/cm under in vitro conditions. Preferably the electric field has a strength of from about 1 V/cm to about 10 kV/cm under in vivo conditions. However, the electric field strengths may be lowered where the number of pulses delivered to the target site are increased. Thus, pulsatile delivery of electric fields at lower field strengths is envisaged.
Preferably the application of the electric field is in the form of multiple pulses such as double pulses of the same strength and capacitance or sequential pulses of varying strength and/or capacitance. As used herein, the term “pulse” includes one or more electric pulses at variable capacitance and voltage and including exponential and/or square wave and/or modulated wave/square wave forms.
Preferably the electric pulse is delivered as a waveform selected from an exponential wave form, a square wave form, a modulated wave form and a modulated square wave form.
A preferred embodiment employs direct current at low voltage. Thus, Applicants disclose the use of an electric field which is applied to the cell, tissue or tissue mass at a field strength of between 1V/cm and 20V/cm, for a period of 100 milliseconds or more, preferably 15 minutes or more.
Ultrasound is advantageously administered at a power level of from about 0.05 W/cm2 to about 100 W/cm2. Diagnostic or therapeutic ultrasound may be used, or combinations thereof.
As used herein, the term “ultrasound” refers to a form of energy which consists of mechanical vibrations the frequencies of which are so high they are above the range of human hearing. Lower frequency limit of the ultrasonic spectrum may generally be taken as about 20 kHz. Most diagnostic applications of ultrasound employ frequencies in the range 1 and 15 MHz′ (From Ultrasonics in Clinical Diagnosis, P. N. T. Wells, ed., 2nd. Edition, Publ. Churchill Livingstone [Edinburgh, London & NY, 1977]).
Ultrasound has been used in both diagnostic and therapeutic applications. When used as a diagnostic tool (“diagnostic ultrasound”), ultrasound is typically used in an energy density range of up to about 100 mW/cm2 (FDA recommendation), although energy densities of up to 750 mW/cm2 have been used. In physiotherapy, ultrasound is typically used as an energy source in a range up to about 3 to 4 W/cm2 (WHO recommendation). In other therapeutic applications, higher intensities of ultrasound may be employed, for example, HIFU at 100 W/cm up to 1 kW/cm2 (or even higher) for short periods of time. The term “ultrasound” as used in this specification is intended to encompass diagnostic, therapeutic and focused ultrasound.
Focused ultrasound (FUS) allows thermal energy to be delivered without an invasive probe (see Morocz et al 1998 Journal of Magnetic Resonance Imaging Vol. 8, No. 1, pp. 136-142. Another form of focused ultrasound is high intensity focused ultrasound (HIFU) which is reviewed by Moussatov et al in Ultrasonics (1998) Vol. 36, No. 8, pp. 893-900 and TranHuuHue et al in Acustica (1997) Vol. 83, No. 6, pp. 1103-1106.
Preferably, a combination of diagnostic ultrasound and a therapeutic ultrasound is employed. This combination is not intended to be limiting, however, and the skilled reader will appreciate that any variety of combinations of ultrasound may be used. Additionally, the energy density, frequency of ultrasound, and period of exposure may be varied.
Preferably the exposure to an ultrasound energy source is at a power density of from about 0.05 to about 100 Wcm-2. Even more preferably, the exposure to an ultrasound energy source is at a power density of from about 1 to about 15 Wcm-2.
Preferably the exposure to an ultrasound energy source is at a frequency of from about 0.015 to about 10.0 MHz. More preferably the exposure to an ultrasound energy source is at a frequency of from about 0.02 to about 5.0 MHz or about 6.0 MHz. Most preferably, the ultrasound is applied at a frequency of 3 MHz.
Preferably the exposure is for periods of from about 10 milliseconds to about 60 minutes. Preferably the exposure is for periods of from about 1 second to about 5 minutes. More preferably, the ultrasound is applied for about 2 minutes. Depending on the particular target cell to be disrupted, however, the exposure may be for a longer duration, for example, for 15 minutes.
Advantageously, the target tissue is exposed to an ultrasound energy source at an acoustic power density of from about 0.05 Wcm-2 to about 10 Wcm-2 with a frequency ranging from about 0.015 to about 10 MHz (see WO 98/52609). However, alternatives are also possible, for example, exposure to an ultrasound energy source at an acoustic power density of above 100 Wcm-2, but for reduced periods of time, for example, 1000 Wcm-2 for periods in the millisecond range or less.
Preferably the application of the ultrasound is in the form of multiple pulses; thus, both continuous wave and pulsed wave (pulsatile delivery of ultrasound) may be employed in any combination. For example, continuous wave ultrasound may be applied, followed by pulsed wave ultrasound, or vice versa. This may be repeated any number of times, in any order and combination. The pulsed wave ultrasound may be applied against a background of continuous wave ultrasound, and any number of pulses may be used in any number of groups.
Preferably, the ultrasound may comprise pulsed wave ultrasound. In a highly preferred embodiment, the ultrasound is applied at a power density of 0.7 Wcm-2 or 1.25 Wcm-2 as a continuous wave. Higher power densities may be employed if pulsed wave ultrasound is used.
Use of ultrasound is advantageous as, like light, it may be focused accurately on a target. Moreover, ultrasound is advantageous as it may be focused more deeply into tissues unlike light. It is therefore better suited to whole-tissue penetration (such as but not limited to a lobe of the liver) or whole organ (such as but not limited to the entire liver or an entire muscle, such as the heart) therapy. Another important advantage is that ultrasound is a non-invasive stimulus which is used in a wide variety of diagnostic and therapeutic applications. By way of example, ultrasound is well known in medical imaging techniques and, additionally, in orthopedic therapy. Furthermore, instruments suitable for the application of ultrasound to a subject vertebrate are widely available and their use is well known in the art.
In example embodiments involving delivery of nucleic acids and/or proteins between populations of cells, delivery of the export compartment to one or more donor cell populations may be used to induce differentiation of one or more recipient cell populations. In some embodiments, differentiation may include inducing a shift in cell state by triggering the activating and/or silencing of one or more gene products and/or cell pathways. In some embodiments, the recipient populations may be stem cells that may be induced to differentiate into one or more cell types. Delivery of the export compartment to the one or more recipient cell populations may be used to induce production of one or more biomolecules by one or more donor cell populations. Such biomolecules may include, but are not necessarily limited to antibodies.
In some embodiments, biomolecules may include aptamers. Aptamers are ssDNA or RNA oligonucleotides that impart high affinity and specific recognition of the target molecules by electrostatic interactions, hydrogen bonding and hydrophobic interactions as opposed to the Watson-Crick base pairing, which is typical for the bonding interactions of oligonucleotides. Aptamers as a targeting moiety can have advantages over antibodies: aptamers can demonstrate higher target antigen recognition as compared with antibodies; aptamers can be more stable and smaller in size as compared with antibodies; aptamers can be easily synthesized and chemically modified for molecular conjugation; and aptamers can be changed in sequence for improved selectivity and can be developed to recognize poorly immunogenic targets.
In some embodiments, delivery of the export compartment to one or more recipient cell populations may be used to induce a shift in cell state by triggering the activating and/or silencing of one or more cell pathways. In some embodiments, exhausted T cells may be reactivated. In some embodiments, cells may be induced to a pro-inflammatory state or to an anti-inflammatory state. In some embodiments, the recipient populations may be isolated ex vivo cells. The isolated ex vivo cells may be modified and used for an adoptive cell therapy. As used herein, “ACT”, “adoptive cell therapy” and “adoptive cell transfer” may be used interchangeably. Adoptive cell therapy (ACT) can refer to the transfer of cells, most commonly immune-derived cells, back into the same patient or into a new recipient host with the goal of transferring the immunologic functionality and characteristics into the new host. If possible, use of autologous cells helps the recipient by minimizing graft-versus-host disease (GVHD) issues. The adoptive transfer of autologous tumor infiltrating lymphocytes (TIL) (Besser et al., (2010) Clin. Cancer Res 16 (9) 2646-55; Dudley et al., (2002) Science 298 (5594): 850-4; and Dudley et al., (2005) Journal of Clinical Oncology 23 (10): 2346-57) or genetically re-directed peripheral blood mononuclear cells (Johnson et al., (2009) Blood 114 (3): 535-46; and Morgan et al., (2006) Science 314(5796) 126-9) has been used to successfully treat patients with advanced solid tumors, including melanoma and colorectal carcinoma, as well as patients with CD19-expressing hematologic malignancies (Kalos et al., (2011) Science Translational Medicine 3 (95): 95ra73).
In some embodiments, delivery of vectors or nucleic acids as described herein may be done in vivo. The donor population may be at or proximate to diseased tissue. One or more cell types that are part of the diseased tissue may be the one or more recipient cells. In some embodiments, uptake of the export compartments may lead to senescence or apoptosis of the recipient cells. Uptake of the export compartments may lead to a shift in cell states within the diseased tissue that treats or ameliorates the disease.
In some embodiments, the invention provides methods of sampling live cells by delivering any of the vectors or nucleic acids described herein to a target population of cells, and inducing expression of the polypeptide to induce export compartment formation and packaging of target nucleic acids and proteins. Export compartments comprising cellular nucleic acid and/or proteins may then be isolated at one or more time points. Methods of sampling live cells at one or more time points can be used for assaying cellular response to stimuli, including differential expression, signaling or other responses to delivery of cargo.
CRISPR based screening methods may also be used, such as for example, by using sgRNA for targeting extracellular vesicle related genes, sgRNA targeting essential genes and non-targeting sgRNA in different cell lines, as shown in the Examples.
The invention may further include a method of treatment comprising administering a pharmaceutical composition as described herein to a subject in need thereof.
As used in this context, to “treat” means to cure, ameliorate, stabilize, prevent, or reduce the severity of at least one symptom or a disease, pathological condition, or disorder. This term includes active treatment, that is, treatment directed specifically toward the improvement of a disease, pathological condition, or disorder, and also includes causal treatment, that is, treatment directed toward removal of the cause of the associated disease, pathological condition, or disorder. In addition, this term includes palliative treatment, that is, treatment designed for the relief of symptoms rather than the curing of the disease, pathological condition, or disorder; preventative treatment, that is, treatment directed to minimizing or partially or completely inhibiting the development of the associated disease, pathological condition, or disorder; and supportive treatment, that is, treatment employed to supplement another specific therapy directed toward the improvement of the associated disease, pathological condition, or disorder. It is understood that treatment, while intended to cure, ameliorate, stabilize, or prevent a disease, pathological condition, or disorder, need not actually result in the cure, amelioration, stabilization or prevention. The effects of treatment can be measured or assessed as described herein and as known in the art as is suitable for the disease, pathological condition, or disorder involved. Such measurements and assessments can be made in qualitative and/or quantitative terms. Thus, for example, characteristics or features of a disease, pathological condition, or disorder and/or symptoms of a disease, pathological condition, or disorder can be reduced to any effect or to any amount.
The term “in need of treatment” as used herein refers to a judgment made by a caregiver (e.g. physician, nurse, nurse practitioner, or individual in the case of humans; veterinarian in the case of animals, including non-human animals) that a subject requires or will benefit from treatment. This judgment is made based on a variety of factors that are in the realm of a caregiver's experience, but that include the knowledge that the subject is ill, or will be ill, as the result of a condition that is treatable by the compounds of the invention.
The administration of compositions, agents, cells, or populations of cells, as disclosed herein may be carried out in any convenient manner including by aerosol inhalation, injection, ingestion, transfusion, implantation or transplantation. The composition may be administered to a patient subcutaneously, intradermally, intratumorally, intranodally, intramedullary, intramuscularly, intrathecally, by intravenous or intralymphatic injection, or intraperitoneally.
It will be appreciated that therapeutic entities in accordance with the invention will be administered with suitable carriers, excipients, and other agents that are incorporated into formulations to provide improved transfer, delivery, tolerance, and the like. A multitude of appropriate formulations can be found in the formulary known to all pharmaceutical chemists: Remington's Pharmaceutical Sciences (15th ed, Mack Publishing Company, Easton, Pa. (1975)), particularly Chapter 87 by Blaug, Seymour, therein. These formulations include, for example, powders, pastes, ointments, jellies, waxes, oils, lipids, lipid (cationic or anionic) containing vesicles (such as Lipofectin™), DNA conjugates, anhydrous absorption pastes, oil-in-water and water-in-oil emulsions, emulsions carbowax (polyethylene glycols of various molecular weights), semi-solid gels, and semi-solid mixtures containing carbowax. Any of the foregoing mixtures may be appropriate in treatments and therapies in accordance with the present invention, provided that the active ingredient in the formulation is not inactivated by the formulation and the formulation is physiologically compatible and tolerable with the route of administration. See also Baldrick P. “Pharmaceutical excipient development: the need for preclinical guidance.” Regul. Toxicol Pharmacol. 32(2):210-8 (2000), Wang W. “Lyophilization and development of solid protein pharmaceuticals.” Int. J. Pharm. 203(1-2):1-60 (2000), Charman W N “Lipids, lipophilic drugs, and oral drug delivery-some emerging concepts.” J Pharm Sci. 89(8):967-78 (2000), Powell et al. “Compendium of excipients for parenteral formulations” PDA J Pharm Sci Technol. 52:238-311 (1998) and the citations therein for additional information related to formulations, excipients and carriers well known to pharmaceutical chemists.
Administration of medicaments of the invention may be by any suitable means that results in a compound concentration that is effective for treating or inhibiting (e.g., by delaying) the development of a disease. The compound is admixed with a suitable carrier substance, e.g., a pharmaceutically acceptable excipient that preserves the therapeutic properties of the compound with which it is administered. One exemplary pharmaceutically acceptable excipient is physiological saline. The suitable carrier substance is generally present in an amount of 1-95% by weight of the total weight of the medicament. The medicament may be provided in a dosage form that is suitable for administration. Thus, the medicament may be in form of, e.g., tablets, capsules, pills, powders, granulates, suspensions, emulsions, solutions, gels including hydrogels, pastes, ointments, creams, plasters, drenches, delivery devices, injectables, implants, sprays, or aerosols.
Methods of administrating the pharmacological compositions, including agonists, antagonists, antibodies or fragments thereof, to an individual include, but are not limited to, intradermal, intrathecal, intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal, epidural, by inhalation, and oral routes. The compositions can be administered by any convenient route, for example by infusion or bolus injection, by absorption through epithelial or mucocutaneous linings (for example, oral mucosa, rectal and intestinal mucosa, and the like), ocular, and the like and can be administered together with other biologically-active agents. Administration can be systemic or local. In addition, it may be advantageous to administer the composition into the central nervous system by any suitable route, including intraventricular and intrathecal injection. Pulmonary administration may also be employed by use of an inhaler or nebulizer, and formulation with an aerosolizing agent. It may also be desirable to administer the agent locally to the area in need of treatment; this may be achieved by, for example, and not by way of limitation, local infusion during surgery, topical application, by injection, by means of a catheter, by means of a suppository, or by means of an implant.
Various delivery systems are known and can be used to administer the pharmacological compositions including, but not limited to, encapsulation in liposomes, microparticles, microcapsules; minicells; polymers; capsules; tablets; and the like. In one embodiment, the agent may be delivered in a vesicle, in particular a liposome. In a liposome, the agent is combined, in addition to other pharmaceutically acceptable carriers, with amphipathic agents such as lipids which exist in aggregated form as micelles, insoluble monolayers, liquid crystals, or lamellar layers in aqueous solution. Suitable lipids for liposomal formulation include, without limitation, monoglycerides, diglycerides, sulfatides, lysolecithin, phospholipids, saponin, bile acids, and the like. Preparation of such liposomal formulations is within the level of skill in the art, as disclosed, for example, in U.S. Pat. Nos. 4,837,028 and 4,737,323. In yet another embodiment, the pharmacological compositions can be delivered in a controlled release system including, but not limited to: a delivery pump (See, for example, Saudek, et al., New Engl. J. Med. 321: 574 (1989) and a semi-permeable polymeric material (See, for example, Howard, et al., J. Neurosurg. 71: 105 (1989)). Additionally, the controlled release system can be placed in proximity of the therapeutic target (e.g., a tumor), thus requiring only a fraction of the systemic dose. See, for example, Goodson, In: Medical Applications of Controlled Release, 1984. (CRC Press, Boca Raton, Fla.).
The amount of the agents which will be effective in the treatment of a particular disorder or condition will depend on the nature of the disorder or condition, and may be determined by standard clinical techniques by those of skill within the art. In addition, in vitro assays may optionally be employed to help identify optimal dosage ranges. The precise dose to be employed in the formulation will also depend on the route of administration, and the overall seriousness of the disease or disorder, and should be decided according to the judgment of the practitioner and each patient's circumstances. Ultimately, the attending physician will decide the amount of the agent with which to treat each individual patient. In certain embodiments, the attending physician will administer low doses of the agent and observe the patient's response. Larger doses of the agent may be administered until the optimal therapeutic effect is obtained for the patient, and at that point the dosage is not increased further. In general, the daily dose range lie within the range of from about 0.001 mg to about 100 mg per kg body weight of a mammal, preferably 0.01 mg to about 50 mg per kg, and most preferably 0.1 to 10 mg per kg, in single or divided doses. On the other hand, it may be necessary to use dosages outside these limits in some cases. In certain embodiments, suitable dosage ranges for intravenous administration of the agent are generally about 5-500 micrograms (μg) of active compound per kilogram (Kg) body weight. Suitable dosage ranges for intranasal administration are generally about 0.01 pg/kg body weight to 1 mg/kg body weight. In certain embodiments, a composition containing an agent of the present invention is subcutaneously injected in adult patients with dose ranges of approximately 5 to 5000 μg/human and preferably approximately 5 to 500 μg/human as a single dose. It is desirable to administer this dosage 1 to 3 times daily. Effective doses may be extrapolated from dose-response curves derived from in vitro or animal model test systems. Suppositories generally contain active ingredient in the range of 0.5% to 10% by weight; oral formulations preferably contain 10% to 95% active ingredient. Ultimately the attending physician will decide on the appropriate duration of therapy using compositions of the present invention. Dosage will also vary according to the age, weight and response of the individual patient.
Methods for administering antibodies for therapeutic use are well known to one skilled in the art. In certain embodiments, small particle aerosols of antibodies or fragments thereof may be administered (see e.g., Piazza et al., J. Infect. Dis., Vol. 166, pp. 1422-1424, 1992; and Brown, Aerosol Science and Technology, Vol. 24, pp. 45-56, 1996). In certain embodiments, antibodies (e.g., anti-CGRP receptor or anti-CGRP antibodies) are administered in metered-dose propellant driven aerosols. In preferred embodiments, antibodies are used as agonists to depress inflammatory diseases or allergen-induced asthmatic responses. In certain embodiments, antibodies may be administered in liposomes, i.e., immunoliposomes (see, e.g., Maruyama et al., Biochim. Biophys. Acta, Vol. 1234, pp. 74-80, 1995). In certain embodiments, immunoconjugates, immunoliposomes or immunomicrospheres containing an agent of the present invention are administered by inhalation.
In certain embodiments, antibodies may be topically administered to mucosa, such as the oropharynx, nasal cavity, respiratory tract, gastrointestinal tract, eye, such as the conjunctival mucosa, vagina, urogenital mucosa, or for dermal application. In certain embodiments, antibodies are administered to the nasal, bronchial or pulmonary mucosa. In order to obtain optimal delivery of the antibodies to the pulmonary cavity in particular, it may be advantageous to add a surfactant such as a phosphoglyceride, e.g. phosphatidylcholine, and/or a hydrophilic or hydrophobic complex of a positively or negatively charged excipient and a charged antibody of the opposite charge.
For dermal application, the antibodies of the present invention may suitably be formulated with one or more of the following excipients: solvents, buffering agents, preservatives, humectants, chelating agents, antioxidants, stabilizers, emulsifying agents, suspending agents, gel-forming agents, ointment bases, penetration enhancers, and skin protective agents.
The dose of antibody required in humans to be effective in the treatment or prevention of allergic inflammation differs with the type and severity of the allergic condition to be treated, the type of allergen, the age and condition of the patient, etc. Typical doses of antibody to be administered are in the range of 1 μg to 1 g, preferably 1-1000 more preferably 2-500, even more preferably 5-50, most preferably 10-20 μg per unit dosage form. In certain embodiments, infusion of antibodies of the present invention may range from 10-500 mg/m2.
In another aspect, provided is a pharmaceutical pack or kit, comprising one or more containers filled with one or more of the ingredients of the pharmaceutical compositions.
A schematic for differential centrifugation, which was the main method used to purify particles, is shown in
Most proteins are located around the lipid dye fractions, as illustrated in
Extracellular vesicles were analyzed by dynamic light scattering, as shown in
The vesicles were also analyzed by Spectradyne particle analysis (
Applicants also tested whether these vesicles are able to transfer these proteins into recipient cells. Multiple methods were used (transwell co-culture, purified EV addition and GFP labeled cell). Overall, results were found to be inconsistent and uptakes to be rare.
Applicants also performed RNA-Seq on extracellular vesicle samples. The general trend was similar with other RNA-Seq that were performed. Future work will involve a deeper Next Generation Sequencing method with more replicates.
Cellular localization of these proteins was also analyzed and there wasn't strong evidence that these proteins localized in vesicles. The localization patterns of these proteins are very different from HIV-gag as well.
Different purification strategies for purifying extracellular vesicles were also tested. Considering the complexity of the protocol and the purity of the samples, differentiation centrifugation and density gradient fractionation seems the most optimal method at the moment.
By using extracellular vesicle enriched protein as carrier, Applicant tagged different cargo with affinity tags (
Four different affinity tags and four different carriers were tested (
Disruption of the exosome pathway appeared to affect cargo enrichment. VPS4B-dn is known to disrupt the ARRDC1 related exosome pathway, while VPS4B-wt does not. VPS4B-dn had an effect on L7 tagged ARRDC1 mediated cargo enrichment (
One proposed reason for low level of transfer is because the extracellular vesicles enter the endosome to lysosome pathway. To increase the direct fusion of the extracellular vesicle and the cytoplasm, Applicants attempted to decorate the surface with the glycoprotein of vesicular stomatitis virus (VSVG). Previous reports suggested that VSVG is able to induce direct fusion between membranes (
Commercially available gesicles showed high level of induction. Gesicles are able to induce over 90% of cells in higher concentration (
Applicants set up a system to produce gesicles in house and test their uptake. Different directing systems using different carrier:VSVG ratios were employed (
Applicants tested the base editor as cargo. Recipient cell to production cell ratio was 1:20 or 1:10 (
Applicants also developed a CRISPR based screening method to better understand the biological pathway related to extracellular vesicle production. Different sgRNA strategies, test enrichments and lenti titers of these libraries were tested. Applicants decided to settle on a construct similar to CROP-Seq (
Applicants performed a preliminary screen with sgRNA targeting extracellular vesicle related genes, sgRNA targeting essential genes and non-targeting sgRNA. The CROP-Seq construct showed clear enrichment of sgRNA targeting certain extracellular vesicle related genes (
A full sized screen was also performed.
Various modifications and variations of the described methods, pharmaceutical compositions, and kits of the invention will be apparent to those skilled in the art without departing from the scope and spirit of the invention. Although the invention has been described in connection with specific embodiments, it will be understood that it is capable of further modifications and that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention that are obvious to those skilled in the art are intended to be within the scope of the invention. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure come within known customary practice within the art to which the invention pertains and may be applied to the essential features herein before set forth.
This application claims the benefit of U.S. Provisional Application No. 62/819,320, filed Mar. 15, 2019. The entire contents of the above-identified application are hereby fully incorporated herein by reference.
This invention was made with government support under Grant No.(s) HL141201 and MH110049 awarded by the National Institutes of Health. The government has certain rights in the invention.
| Number | Date | Country | |
|---|---|---|---|
| 62819320 | Mar 2019 | US |
