Despite antiretroviral therapy (ART), HIV-1 persists in a stable latent reservoir1,2, primarily in resting memory CD4+ T cells3, 4. This reservoir presents a major barrier to the cure of HIV-1 infection. To purge the reservoir, pharmacological reactivation of latent HIV-1 has been proposed5 and tested both in vitro and in vivo6-8. A key remaining question is whether virus-specific immune mechanisms including cytolytic T lymphocytes (CTL) can clear infected cells in ART-treated patients after latency is reversed. Here we show that there is a striking all or none pattern for CTL escape mutations in HIV-1 Gag epitopes. Unless ART is started early, the vast majority (>98%) of latent viruses carry CTL escape mutations that render infected cells insensitive to CTLs directed at common epitopes. To solve this problem, we identified CTLs that could recognize epitopes from latent HIV-1 that were unmutated in every chronically infected patient tested. Upon stimulation, these CTLs eliminated target cells infected with autologous virus derived from the latent reservoir, both in vitro and in patient-derived humanized mice. The predominance of CTL-resistant viruses in the latent reservoir poses a major challenge to viral eradication. Our results demonstrate that chronically infected patients retain a broad spectrum viral-specific CTL response and that appropriate boosting of this response may be required for the elimination of the latent reservoir.
HIV-1 establishes latent infection in resting CD4+ T cells3, 4. Recent efforts to eradicate HIV-1 infection have focused on reversing latency without global T cell activation5. However, inducing HIV-1 gene expression in latently infected cells is not sufficient to cause the death of these cells if they remain in a resting state9. Boosting HIV-1-specific immune responses including CTL responses may be required for clearance of the latent reservoir9. CTLs play a significant role in suppressing HIV-1 replication in acute infection10-14. Because of this strong selective pressure, HIV-1 quickly acquires mutations to evade CTL recognition12, 13, 15-18. CTL escape has been studied primarily through the analysis of plasma virus12, 13, 16, 18-20, and CTL-based vaccines have been designed based on conserved epitopes21, 22. A systematic investigation of CTL escape in the latent reservoir will be of great importance to the ongoing CTL-based eradication efforts, because latent HIV-1 likely represents the major source of viral rebound after treatment interruption. Earlier studies have suggested the presence of CTL escape mutations in proviral DNA15, 17, but it still remains unclear to what extent the latent reservoir in resting CD4+ T cells is affected by CTL escape, whether mutations detected in proviral DNA are representative of the very small fraction of proviruses that are replication-competent, and most importantly, whether the CTL response can recognize and clear infected cells after latency is reversed. Provided herein, in part, is a CD8+ T cell vaccine or therapy for use against latent HIV-1 infection.
Provided herein are methods of preventing or treating a HIV infection in a mammal, such as a human. The methods involve administrating to a mammal in need thereof, a therapeutically effective amount of a CD8+ T cell vaccine composition. Such methods comprise using a CD8+ T cell vaccine composition which has been pre-stimulated with at least one HIV epitope, such as a HIV-1 Gag epitope, or a pool or mixture of HIV epitopes. The vaccine induces and enhances a CD8+ T cell immune response against HIV/AIDS in said mammal.
One aspect of the invention relates to a method of preventing or treating a HIV infection comprising administering to a mammal in need thereof, a therapeutically effective amount of a CD8+ T cell vaccine composition, wherein the CD8+ T cell has been pre-stimulated with at least one HIV epitope, to thereby enhance a CD8+ T cell immune response against HIV.
In certain embodiments, the pre-stimulation occurs ex-vivo.
In certain embodiments, the CD8+ T cell has been pre-stimulated with at least two, three, four, five, six, seven, eight, nine, or ten HIV epitopes.
In certain embodiments, the at least one HIV epitope is a subdominant epitope.
In certain embodiments, the at least one HIV epitope is a dominant epitope.
In certain embodiments, the HIV epitopes comprise subdominant and dominant epitopes.
In certain embodiments, the at least one HIV epitope is from HIV-1.
In certain embodiments, the at least one HIV epitope is selected from an epitope in the HIV-1 Gag, HIV-1 Nef, HIV-1 Rev, HIV-1 Tat, or HIV-1 Env, or combination thereof.
In certain embodiments, the at least one HIV epitope is provided in a pool or mixture of HIV epitopes.
In certain embodiments, the pool or mixture of HIV epitope is a pool or mixture of HIV-1 Gag, HIV-1 Nef, HIV-1 Rev, HIV-1 Tat, HIV-1 Env, or combination thereof.
In certain embodiments, the pool or mixture of HIV epitope is a pool or mixture of HIV-1 Gag represented by the peptide sequences set forth in Table 2, Table 4, or both.
In certain embodiments, the pool or mixture of HIV epitope is a pool or mixture of HIV-1 Nef represented by the peptide sequences set forth in Table 3.
In certain embodiments, the pool or mixture of HIV epitope is a pool or mixture of HIV-1 Rev represented by the peptide sequences set forth in Table 5.
In certain embodiments, the pool or mixture of HIV epitope is a pool or mixture of HIV-1 Tat represented by the peptide sequences set forth in Table 7.
In certain embodiments, the pool or mixture of HIV epitope is a pool or mixture of HIV-1 Env represented by the peptide sequences set forth in Table 6.
In certain embodiments, the at least one HIV epitope is an epitope in the HIV-1 Gag.
In certain embodiments, the epitope in the HIV-1 Gag is selected from any one of SEQ ID NOs: 1-17, or combination thereof.
In certain embodiments, the HIV-1 Gag is from proviral HIV-1 DNA in resting CD4+ T cells from mammals during the acute phase or chronic phase of infection.
In certain embodiments, the at least one HIV epitope is synthetic.
In certain embodiments, the at least one HIV epitope is unmutated.
In certain embodiments, the at least one HIV epitope is mutated.
In certain embodiments, the CD8+ T cell immune response is to subdominant epitope in HIV-1.
In certain embodiments, the CD8+ T cell is from CP36 or CP39.
In certain embodiments, the CD8+ T cell is autologous.
In certain embodiments, the CD8+ T cell has been pre-stimulated with at least one HIV epitope and at lease one cytokine.
In certain embodiments, the at least one cytokine is interleukin-2 (IL-2).
In certain embodiments, the CD8+ T cell to CD4+ T cell ratio is enhanced.
In certain embodiments, the CD8+ T cell response targets latent or reactivated HIV-1 infected cells.
In certain embodiments, the CD8+ T cell immune response is greater in magnitude than a CD8+ T cell immune response induced by administration of an unstimulated CD8+ T cell composition.
In certain embodiments, the CD8+ T cell immune response is greater in magnitude than a CD8+ T cell immune response induced by administration of the HIV epitope alone.
In certain embodiments, the efficacy of the immune response against HIV results in a reduction of the levels of HIV viral replication.
In certain embodiments, the reduction of levels of HIV viral replication is decreased in log10 reductions of about 2-logs, 3-logs, 4-logs, 5-logs, 6-logs, 7-logs, 8-logs, or 9-logs.
In certain embodiments, the efficacy of the immune response against HIV results in a reduction of levels of plasma HIV-1 RNA.
In certain embodiments, the reduction of the levels of plasma HIV-1 RNA is in log10 reductions of about 2-logs, 3-logs, 4-logs, 5-logs, 6-logs, 7-logs, 8-logs, or 9-logs.
In certain embodiments, the efficacy of the immune response against HIV results in a reduction of levels of proviral HIV-1 DNA.
In certain embodiments, the levels of provrial HIV-1 DNA is decreased 100-, 200-, 300-, 400-, 500-, 600-, 700-, 800-, 900-, 1000-, 1500-, or 2000-fold.
In certain embodiments, the efficacy of the immune response against HIV results in a reduction of the HIV-1 latent reservoir.
In certain embodiments, the HIV-1 latent reservoir is decreased 100-, 200-, 300-, 400-, 500-, 600-, 700-, 800-, 900-, 1000-, 1500-, or 2000-fold when compared to the resting CD4+ T cell population in any healthy or infected individual or total latently infected resting CD4+ T cell population.
In certain embodiments, the resting CD4+ T cell population in any healthy or infected individual about 1012 cells.
In certain embodiments, the total latently infected resting CD4+T cell population is from about 106 to about 107 cells.
In certain embodiments, the efficacy of the immune response against HIV results in a delay in rebound of HIV viremia after cessation of antiretroviral therapy.
In certain embodiments, the delay is measured in months of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 months.
In certain embodiments, the mammal is a human.
In certain embodiments, the human is afflicted with HIV-1.
In certain embodiments, the human is chronically infected with HIV-1.
In certain embodiments, the human is acutely infected with HIV-1.
In certain embodiments, the CD8+ T cell vaccine composition is administered to a human on suppressive antiretroviral therapy.
In certain embodiments, the CD8+ T cell vaccine composition is administered to the antiretroviral-treated human followed by antiretroviral treatment interruption.
In certain embodiments, the CD8+ T cell vaccine composition is administered to the antiretroviral-treated human in combination with latency reversing therapy.
In certain embodiments, the composition is administered to the mammal more than one time over the course of treating or preventing.
In certain embodiments, the composition is administered to the mammal in need thereof at about weeks two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen, and sixteen post-HIV infection.
In certain embodiments, the therapeutically effective amount is about 102, 103, 104, 105, 106, 107, 108, 109, 1010, 1011, or 1012 prestimulated CD8+ T cells per infusion into a patient.
In certain embodiments, the effective amount is between about 107 to 109 prestimulated CD8+ T cells per infusion into a patient.
Other objects, features and advantages of the present invention will become apparent from the following detailed description. It should be understood, however, that the detailed description and the specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
For convenience, certain terms employed in the specification, examples, and appended claims are collected here. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
The articles “a” and “an” are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element.
The term “administering” includes any method of delivery of a compound of the present invention, including but not limited to, a pharmaceutical composition, therapeutic agent, or CD8+ T cell vaccine composition into a subject's system or to a particular region in or on a subject. The phrases “systemic administration,” “administered systemically,” “peripheral administration,” “administered peripherally,” “infusion,” and “reinfusion” as used herein mean the administration of a compound, drug, CD8+ T cell vaccine composition, or other material other than directly into the central nervous system, such that it enters the patient's system and, thus, is subject to metabolism and other like processes, for example, subcutaneous administration. “Parenteral administration” and “administered parenterally” means modes of administration other than enteral and topical administration, usually by injection, and includes, without limitation, intravenous, intramuscular, intraarterial, intrathecal, intracapsular, intraorbital, intracardiac, intradermal, intraperitoneal, transtracheal, subcutaneous, subcuticular, intra-articular, subcapsular, subarachnoid, intraspinal and intrasternal injection and infusion.
The term “amino acid” is known in the art. In general the abbreviations used herein for designating the amino acids and the protective groups are based on recommendations of the IUPAC-IUB Commission on Biochemical Nomenclature (see Biochemistry (1972) 11:1726-1732). In certain embodiments, the amino acids used in the application of this invention are those naturally occurring amino acids found in proteins, or the naturally occurring anabolic or catabolic products of such amino acids which contain amino and carboxyl groups. Particularly suitable amino acid side chains include side chains selected from those of the following amino acids: glycine, alanine, valine, cysteine, leucine, isoleucine, serine, threonine, methionine, glutamic acid, aspartic acid, glutamine, asparagine, lysine, arginine, proline, histidine, phenylalanine, tyrosine, and tryptophan.
Also included are the (d) and (l) stereoisomers of such amino acids when the structure of the amino acid admits of stereoisomeric forms. The configuration of the amino acids and amino acid residues herein are designated by the appropriate symbols (d), (l) or (dl). Furthermore, when the configuration is not designated the amino acid or residue can have the configuration (d), (l) or (dl). It is to be understood accordingly that the isomers arising from such asymmetry are included within the scope of this invention. Such isomers can be obtained in substantially pure form by classical separation techniques and by sterically controlled synthesis. For the purposes of this application, unless expressly noted to the contrary, a named amino acid shall be construed to include both the (d) or (l) stereoisomers.
The terms “comprise” and “comprising” are used in the inclusive, open sense, meaning that additional elements may be included.
The term “HIV” is known to one skilled in the art to refer to Human Immunodeficiency Virus. There are two types of HIV: HIV-1 and HIV-2. There are many different strains of HIV-1. The strains of HIV-1 can be classified into three groups: the “major” group M, the “outlier” group O and the “new” group N. These three groups may represent three separate introductions of simian immunodeficiency virus into humans. Within the M-group there are at least ten subtypes or clades: e.g., clade A, B, C, D, E, F, G, H, I, J, and K. A “clade” is a group of organisms, such as a species, whose members share homologous features derived from a common ancestor. Any reference to HIV-1 in this application includes all of these strains.
The term “including” is used to mean “including but not limited to”. “Including” and “including but not limited to” are used interchangeably.
A “patient” or “subject” or “mammal” refers to either a human or non-human animal.
The term “pharmaceutical delivery device” refers to any device that may be used to administer a therapeutic agent or agents to a subject. Non-limiting examples of pharmaceutical delivery devices include hypodermic syringes, multichamber syringes, stents, catheters, transcutaneous patches, microneedles, microabraders, and implantable controlled release devices.
The phrase “pharmaceutically acceptable” is employed herein to refer to those compounds, materials, compositions, and/or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.
The phrase “pharmaceutically-acceptable carrier” as used herein means a pharmaceutically-acceptable material, composition or vehicle, such as a liquid or solid filler, diluent, excipient, or solvent encapsulating material, involved in carrying or transporting the subject compound from one organ, or portion of the body, to another organ, or portion of the body. Each carrier must be “acceptable” in the sense of being compatible with the other ingredients of the formulation and not injurious to the patient. Some examples of materials which can serve as pharmaceutically-acceptable carriers include: (1) sugars, such as lactose, glucose and sucrose; (2) starches, such as corn starch and potato starch; (3) cellulose, and its derivatives, such as sodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate; (4) powdered tragacanth; (5) malt; (6) gelatin; (7) talc; (8) excipients, such as cocoa butter and suppository waxes; (9) oils, such as peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil and soybean oil; (10) glycols, such as propylene glycol; (11) polyols, such as glycerin, sorbitol, mannitol and polyethylene glycol; (12) esters, such as ethyl oleate and ethyl laurate; (13) agar; (14) buffering agents, such as magnesium hydroxide and aluminum hydroxide; (15) alginic acid; (16) pyrogen-free water; (17) isotonic saline; (18) Ringer's solution; (19) ethyl alcohol; (20) pH buffered solutions; (21) polyesters, polycarbonates and/or polyanhydrides; and (22) other non-toxic compatible substances employed in pharmaceutical formulations.
The terms “polypeptide”, “peptide” and “epitope” are used interchangeably herein to refer to polymers of amino acids. The polymer may be linear or branched, it may comprise modified amino acids, and it may be interrupted by non-amino acids. The terms also encompass an amino acid polymer that has been modified; for example, disulfide bond formation, glycosylation, lipidation, acetylation, phosphorylation, or any other manipulation, such as conjugation with a labeling component.
In certain embodiments, peptides of the invention may be synthesized chemically, ribosomally in a cell free system, or ribosomally within a cell. Chemical synthesis of polypeptides of the invention may be carried out using a variety of art recognized methods, including stepwise solid phase synthesis, semi-synthesis through the conformationally-assisted re-ligation of peptide fragments, enzymatic ligation of cloned or synthetic peptide segments, and chemical ligation. Native chemical ligation employs a chemoselective reaction of two unprotected peptide segments to produce a transient thioester-linked intermediate. The transient thioester-linked intermediate then spontaneously undergoes a rearrangement to provide the full length ligation product having a native peptide bond at the ligation site. Full length ligation products are chemically identical to proteins produced by cell free synthesis. Full length ligation products may be refolded and/or oxidized, as allowed, to form native disulfide-containing protein molecules (see e.g., U.S. Pat. Nos. 6,184,344 and 6,174,530; and T. W. Muir et al., Curr. Opin. Biotech. (1993): vol. 4, p 420; M. Miller, et al., Science (1989): vol. 246, p 1149; A. Wlodawer, et al., Science (1989): vol.
245, p 616; L. H. Huang, et al., Biochemistry (1991): vol. 30, p 7402; M. Schnolzer, et al., Int. J. Pept. Prot. Res. (1992): vol. 40, p 180-193; K. Rajarathnam, et al., Science (1994): vol. 264, p 90; R. E. Offord, “Chemical Approaches to Protein Engineering”, in Protein Design and the Development of New therapeutics and Vaccines, J. B. Hook, G. Poste, Eds., (Plenum Press, New York, 1990) pp. 253-282; C. J. A. Wallace, et al., J. Biol. Chem. (1992): vol. 267, p 3852; L. Abrahmsen, et al., Biochemistry (1991): vol. 30, p 4151; T. K. Chang, et al., Proc. Natl. Acad. Sci. USA (1994) 91: 12544-12548; M. Schnlzer, et al., Science (1992): vol., 3256, p 221; and K. Akaji, et al., Chem. Pharm. Bull. (Tokyo) (1985) 33: 184).
As known to one skilled in the art, “retroviruses” are diploid positive-strand RNA viruses that replicate through an integrated DNA intermediate (proviral DNA). In particular, upon infection by the RNA virus, the lentiviral genome is reverse-transcribed into DNA by a virally encoded reverse transcriptase that is carried as a protein in each retrovirus. The viral DNA is then integrated pseudo-randomly into the host cell genome of the infecting cell, forming a “provirus” which is inherited by daughter cells. The retrovirus genome contains at least three genes: Gag codes for core and structural proteins of the virus; Pol codes for reverse transcriptase, protease and integrase; and Env codes for the virus surface proteins. Within the retrovirus family, HIV is classified as a lentivirus, having genetic and morphologic similarities to animal lentiviruses such as those infecting cats (feline immunodeficiency virus), sheep (visna virus), goats (caprine arthritis-encephalitis virus), and non-human primates (simian immunodeficiency virus).
Provided are methods of preventing or treating a lentiviral infection, such as a HIV infection, comprising administering to a mammal in need thereof, a therapeutically effective amount of a CD8+ T cell vaccine composition, wherein the CD8+ T cell has been pre-stimulated with at least one HIV epitope, to thereby enhance a CD8+ T cell immune response against HIV.
The term “effective amount” as used herein means an amount effective and at dosages and for periods of time necessary to achieve the desired result. The term “mammal” as used herein includes all members of the animal kingdom including non-humans and humans. In certain embodiments, the mammal may be a human. The human may be afflicted with HIV-1. The human may be chronically infected or acutely infected with HIV-1. The human may be on suppressive antiretroviral therapy. In certain embodiments, the pre-stimulated CD8+ T cell vaccine composition can be reinfused only in antiretroviral therapy (ART)-treated individuals, reinfused only in untreated individuals, reinfused only in ART-treated individuals, followed by antiretroviral treatment interruption, or reinfused combined with latency reversing therapy in ART-treated individuals.
In certain embodiments, the CD8+ T cell vaccine composition is administered to the patient more than one time over the course of treating or preventing.
In certain embodiments, the efficacy of the CD8+ T cell vaccine composition may relate to HIV latency and the ability to remain off of antiretroviral therapy without HIV rebound. In certain embodiments, these measures include reduction in proviral DNA. The estimated number of HIV proviruses per infected person on therapy are 108 to 109. In certain embodiments, the reductions in proviral DNA that result in a delay in rebound may be on the order of about 100- to 1000-fold reductions. In other embodiments, these measures included reduction in the total number of resting CD4+ T cells in any healthy or infected individual would be approximately 1012 using well-known methods in the art of measuring reservoir size. In other embodiments, these measures included reduction in the total latently infected resting CD4 T cell population appears to be between 106 and 107 cells. In certain embodiments, a 1000-fold reduction would result in significant delay in rebound when off antiretroviral therapy. In other embodiments, efficacy is measured in delay in rebound of HIV viremia after cessation of antiretroviral therapy measured in months.
A therapeutically effective amount of a CD8+ T cell vaccine composition comprises CD8+ T cells which have been pre-stimulated with at least one HIV epitope, to thereby enhance a CD8+ T cell immune response.
The pre-stimulation occurs ex-vivo and may include incubating the CD8+ T cells with at least one cytokine in addition to the at least one HIV epitope. The CD8+ T cell may be derived from CP36 or CP39. The CD8+ T cell may be autologous to the mammal.
The HIV epitopes may include at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, 125, 150, 175, 200, 225, 250, 275, 300, 325, 350, 375, 400, 425, 450, 475, or 500 HIV epitopes. The at least one HIV epitope may be a subdominant or dominant epitope. The at least two HIV epitopes may comprise subdominant and dominant epitopes.
In certain embodiments, the CD8+ T cell response may target latent or reactivated HIV-1 infected cells. In certain embodiments, the CD8+ T cell immune response may be greater in magnitude than a CD8+ T cell immune response induced by administration of an unstimulated CD8+ T cell composition. In other embodiments, the CD8+ T cell immune response is greater in magnitude than a CD8+ T cell immune response induced by administration of the HIV epitope alone. The CD8+ T cell immune response may be in response to a subdominant epitope(s) in HIV-1.
In certain embodiments, the at least one HIV epitope may be from HIV-1. In certain embodiments, the at least one HIV epitope may be from HIV-2. In certain embodiments, the at least one HIV epitope may be selected from an epitope in the HIV-1 Gag, HIV-1 Nef, HIV-1 Rev, HIV-1 Tat, or HIV-1 Env. In certain embodiments, the HIV epitope may be provided singly, or in combination as a mixture or pool of HIV peptides. In certain embodiments, the pool or mixture of HIV peptides are defined by the Gag peptides in Table 2 and Table 4 (i.e., NIH AIDS Reagent 8117). In certain embodiments, the pool or mixture of HIV peptides are defined by the Nef peptides in Table 3 (i.e., NIH AIDS Reagent 5189). In certain embodiments, the pool or mixture of HIV peptides are defined by the Rev peptides in Table 5 (i.e., NIH AIDS Reagent 6445). In certain embodiments, the pool or mixture of HIV peptides are defined by the Tat peptides in Table 7 (i.e., NIH AIDS Reagent 5138). In certain embodiments, the pool or mixture of HIV peptides are defined by the Env peptides in Table 6 (i.e., NIH AIDS Reagent 9480). Said mixtures or pools of HIV peptides may comprise different combinations of the HIV peptides set for the in Tables 2-7. In certain embodiments, the at least one HIV epitope is an epitope in HIV-1 Gag. In certain embodiments, the HIV-1 Gag epitopes may be selected from ISPRTLNAW (SEQ ID NO: 1), LSPRTLNAW (SEQ ID NO: 2), TSTLQEQIGW (SEQ ID NO: 3), TSNLQEQIGW (SEQ ID NO: 4), QASQEVKNW (SEQ ID NO: 5), QSTQEVKNW(SEQ ID NO: 6), KAFSPEVIPMF (SEQ ID NO: 7), SLYNTVATL (SEQ ID NO: 8), SLFNTVAVL (SEQ ID NO: 9), WASRELERF (SEQ ID NO: 10), TLNAWVKVV (SEQ ID NO: 11), RLRPGGKKK (SEQ ID NO: 12), RLRPGGKKS (SEQ ID NO: 13), LYNTVATLY (SEQ ID NO: 14), LFNTIAALF (SEQ ID NO: 15), TPQDLNTML (SEQ ID NO: 16), or GPGHKARVL (SEQ ID NO: 17). In certain embodiments, the HIV Env epitope is found in the consensus Subtype B sequence as follows:
In certain embodiments, the HIV epitope may be synthetic and may be chemically synthesized as described in section “A” above. In other embodiments, the HIV epitopes may be mutated or unmutated. Other HIV epitopes may be deep sequences from from proviral HIV-1 DNA in resting CD4+ T cells from mammals during the acute phase or chronic phase of infection (see examples section of instant specification).
The present invention further features methods comprising the administration of an effective amount a CD8+ T cell vaccine composition, wherein the composition comprises CD8+ T cells which have been pre-stimulated with at least one HIV epitope, or a pool or mixure of HlVepitodes set forth in Tables 2-7, to thereby enhance a CD8+ T cell immune response, as described above. Dosage levels of between about 102, 103, 104, 105, 106, 107, 108, 109, 1010, 1011, or 1012 cells per infusion into a patient may be useful as a vaccine injection in the methods described herein. The amount of active ingredient that may be combined with the carrier materials to produce a single dosage form will vary depending upon the host treated and the particular mode of administration. The dose of the vaccine may vary according to factors such as the infection state, age, sex, and weight of the individual, and the ability of CD8+ T cell vaccine composition to elicit a desired response in the individual. Dosage regime may be adjusted to provide the optimum therapeutic response. For example, several divided doses may be administered daily or the dose may be proportionally reduced as indicated by the exigencies of the therapeutic situation. The dose of the vaccine may also be varied to provide optimum preventative or treatment dose response depending upon the circumstances.
In certain embodiments, the dosage may enhance the CD8+ T cell to CD4+ T cell ratio. The efficacy of the prevention or treatment of the methods of the present invention may be determined from samples obtained from the mammal after treatment has began using the following. In certain embodiments, the efficacy is determined comparing a sample of a mammal obtained during the course of treatment to a sample which has been previously obtained from the patient, such as at the start of treatment or in an initial sample obtained two, three, or four weeks post HIV infection but prior to treatment. In certain embodiments, the levels of HIV viral replication is decreased in a plasma sample when compared to a plasma sample previously obtained from the mammal prior to initiation of treatment. The levels of HIV viral replication may be decreased in terms of log10 reductions of about 2-logs, 3-logs, 4-logs, 5-logs, 6-logs, 7-logs, 8-logs, or 9-logs. In certain embodiments, the levels of plasma HIV-1 RNA may be decreased in a plasma sample when compared to a plasma sample previously obtained from the mammal prior to initiation of treatment. The levels of plasma HIV-1 RNA may be decreased in terms of log10 reductions of about 2-logs, 3-logs, 4-logs, 5-logs, 6-logs, 7-logs, 8-logs, or 9-logs. In other embodiments, the levels of proviral HIV-1 DNA may be decreased 100-, 200-, 300-, 400-, 500-, 600-, 700-, 800-, 900-, 1000-, 1500-, or 2000-fold. The fold reduction may be calculated as a reduction from an estimated 108 or 109 HIV provirus per infected person on antiretroviral therapy. In other embodiments, the efficacy of the CD8+ T cell vaccine composition can be determined when the HIV-1 latent reservoir is decreased 100-, 200-, 300-, 400-, 500-, 600-, 700-, 800-, 900-, 1000-, 1500-, or 2000-fold when compared to the resting CD4+ T cell population in any healthy or infected individual or total latently infected resting CD4+ T cell population using well known methods in the art to measure the reservoir size. In certain embodiments, the resting CD4+ T cell population in any healthy or infected individual is about 1012 cells. In certain embodiments, the total latently infected resting CD4+ T cell population is from about 106 to about 107 cells. Such fold reductions may result in significant delay in rebound when off of antiretroviral therapy. In other embodiments, the efficacy of the CD8+ T cell vaccine composition relate to HIV latency and the ability of the patient to remain off of antiretroviral therapy without HIV rebound. In certain embodiments, efficacy of the CD8+ T cell vaccine composition can be determined by the delay in rebound of HIV viremia after cessation of antiretroviral therapy. Typically, a rebound of HIV viremia may occur in a couple of weeks in patients who have stopped antiretroviral therapy. In certain embodiments a significant delay may be measured in months of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or 11 months.
The compositions of the invention are suitable for administration to subjects in a biologically compatible form in vivo. The expression “biologically compatible form suitable for administration in vivo” as used herein means a form of the substance to be administered in which any toxic effects are outweighed by the therapeutic effects. The substances may be administered to any animal, preferably humans.
The CD8+ T cell vaccine composition of the present invention may additionally contain suitable diluents, adjuvants and/or carriers. Preferably, the vaccines contain an adjuvant which can enhance the immunogenicity of the vaccine in vivo. The adjuvant may be selected from many known adjuvants in the art including the lipid-A portion of gram negative bacteria endotoxin, trehalose dimycolate of mycobacteria, the phospholipid lysolecithin, dimethyldictadecyl ammonium bromide (DDA), certain linear polyoxypropylene-polyoxyethylene (POP-POE) block polymers, aluminum hydroxide, liposomes and CpG (cytosine-phosphate-guanidine) polymers. The vaccines may also include cytokines that are known to enhance the immune response including GM-CSF, IL-2, IL-12, TNF and IFNγ.
The vaccines of the instant invention may be formulated and introduced as a vaccine through oral, intradermal, intramuscular, intraperitoneal, intravenous, subcutaneous, intranasal, and intravaginal, or any other standard route of immunization.
In formulations of the subject vaccines, wetting agents, emulsifiers and lubricants, such as sodium lauryl sulfate and magnesium stearate, as well as coloring agents, releasing agents, coating agents, sweetening, flavoring and perfuming agents, preservatives and antioxidants may be present in the formulated agents.
Subject compositions may be suitable for oral, nasal, topical (including buccal and sublingual), rectal, vaginal, aerosol and/or parenteral administration. The formulations may conveniently be presented in unit dosage form and may be prepared by any method well known in the art of pharmacy. The amount of composition that may be combined with a carrier material to produce a single dose may vary depending upon the subject being treated, and the particular mode of administration.
Methods of preparing these formulations include the step of bringing into association compositions of the present invention with the carrier and, optionally, one or more accessory ingredients. In general, the formulations are prepared by uniformly and intimately bringing into association agents with liquid carriers, or finely divided solid carriers, or both, and then, if necessary, shaping the product.
Formulations suitable for oral administration may be in the form of capsules, cachets, pills, tablets, lozenges (using a flavored basis, usually sucrose and acacia or tragacanth), powders, granules, or as a solution or a suspension in an aqueous or non-aqueous liquid, or as an oil-in-water or water-in-oil liquid emulsion, or as an elixir or syrup, or as pastilles (using an inert base, such as gelatin and glycerin, or sucrose and acacia), each containing a predetermined amount of a subject composition thereof as an active ingredient. Compositions of the present invention may also be administered as a bolus, electuary, or paste.
In solid dosage forms for oral administration (capsules, tablets, pills, dragees, powders, granules and the like), the subject composition is mixed with one or more pharmaceutically acceptable carriers, such as sodium citrate or dicalcium phosphate, and/or any of the following: (1) fillers or extenders, such as starches, lactose, sucrose, glucose, mannitol, and/or silicic acid; (2) binders, such as, for example, carboxymethylcellulose, alginates, gelatin, polyvinyl pyrrolidone, sucrose and/or acacia; (3) humectants, such as glycerol; (4) disintegrating agents, such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, and sodium carbonate; (5) solution retarding agents, such as paraffin; (6) absorption accelerators, such as quaternary ammonium compounds; (7) wetting agents, such as, for example, acetyl alcohol and glycerol monostearate; (8) absorbents, such as kaolin and bentonite clay; (9) lubricants, such a talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate, and mixtures thereof; and (10) coloring agents. In the case of capsules, tablets and pills, the compositions may also comprise buffering agents. Solid compositions of a similar type may also be employed as fillers in soft and hard-filled gelatin capsules using such excipients as lactose or milk sugars, as well as high molecular weight polyethylene glycols and the like.
A tablet may be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared using binder (for example, gelatin or hydroxypropylmethyl cellulose), lubricant, inert diluent, preservative, disintegrant (for example, sodium starch glycolate or cross-linked sodium carboxymethyl cellulose), surface-active or dispersing agent. Molded tablets may be made by molding in a suitable machine a mixture of the subject composition moistened with an inert liquid diluent. Tablets, and other solid dosage forms, such as dragees, capsules, pills and granules, may optionally be scored or prepared with coatings and shells, such as enteric coatings and other coatings well known in the pharmaceutical-formulating art.
Liquid dosage forms for oral administration include pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. In addition to the subject composition, the liquid dosage forms may contain inert diluents commonly used in the art, such as, for example, water or other solvents, solubilizing agents and emulsifiers, such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor and sesame oils), glycerol, tetrahydrofuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, and mixtures thereof.
Suspensions, in addition to the subject composition, may contain suspending agents as, for example, ethoxylated isostearyl alcohols, polyoxyethylene sorbitol and sorbitan esters, microcrystalline cellulose, aluminum metahydroxide, bentonite, agar-agar and tragacanth, and mixtures thereof.
Formulations for rectal or vaginal administration may be presented as a suppository, which may be prepared by mixing a subject composition with one or more suitable non-irritating excipients or carriers comprising, for example, cocoa butter, polyethylene glycol, a suppository wax or a salicylate, and which is solid at room temperature, but liquid at body temperature and, therefore, will melt in the body cavity and release the active agent. Formulations, which are suitable for vaginal administration also include pessaries, tampons, creams, gels, pastes, foams or spray formulations containing such carriers as are known in the art to be appropriate.
Dosage forms for transdermal administration of a subject composition includes powders, sprays, ointments, pastes, creams, lotions, gels, solutions, patches and inhalants. The active component may be mixed under sterile conditions with a pharmaceutically acceptable carrier, and with any preservatives, buffers, or propellants, which may be required.
The ointments, pastes, creams and gels may contain, in addition to a subject composition, excipients, such as animal and vegetable fats, oils, waxes, paraffins, starch, tragacanth, cellulose derivatives, polyethylene glycols, silicones, bentonites, silicic acid, talc and zinc oxide, or mixtures thereof.
Powders and sprays may contain, in addition to a subject composition, excipients such as lactose, talc, silicic acid, aluminum hydroxide, calcium silicates and polyamide powder, or mixtures of these substances. Sprays may additionally contain customary propellants, such as chlorofluorohydrocarbons and volatile unsubstituted hydrocarbons, such as butane and propane.
Compositions of the present invention may alternatively be administered by aerosol. This is accomplished by preparing an aqueous aerosol, liposomal preparation or solid particles containing the compound. A non-aqueous (e.g., fluorocarbon propellant) suspension could be used. Sonic nebulizers may be used because they minimize exposing the agent to shear, which may result in degradation of the compounds contained in the subject compositions.
Ordinarily, an aqueous aerosol is made by formulating an aqueous solution or suspension of a subject composition with conventional pharmaceutically acceptable carriers and stabilizers. The carriers and stabilizers vary with the requirements of the particular subject composition, but typically include non-ionic surfactants (Tweens, Pluronics, or polyethylene glycol), innocuous proteins like serum albumin, sorbitan esters, oleic acid, lecithin, amino acids such as glycine, buffers, salts, sugars or sugar alcohols. Aerosols generally are prepared from isotonic solutions.
In addition, vaccines may be administered parenterally as injections (intravenous, intramuscular or subcutaneous). The vaccine compositions of the present invention may optionally contain one or more adjuvants. Any suitable adjuvant can be used, such as CpG polymers, aluminum hydroxide, aluminum phosphate, plant and animal oils, and the like, with the amount of adjuvant depending on the nature of the particular adjuvant employed. In addition, the anti-infective vaccine compositions may also contain at least one stabilizer, such as carbohydrates such as sorbitol, mannitol, starch, sucrose, dextrin, and glucose, as well as proteins such as albumin or casein, and buffers such as alkali metal phosphates and the like.
Pharmaceutical compositions of this invention suitable for parenteral administration comprise a subject composition in combination with one or more pharmaceutically-acceptable sterile isotonic aqueous or non-aqueous solutions, dispersions, suspensions or emulsions, or sterile powders which may be reconstituted into sterile injectable solutions or dispersions just prior to use, which may contain antioxidants, buffers, bacteriostats, solutes which render the formulation isotonic with the blood of the intended recipient or suspending or thickening agents.
Examples of suitable aqueous and non-aqueous carriers, which may be employed in the pharmaceutical compositions of the invention, include water, ethanol, polyols (such as glycerol, propylene glycol, polyethylene glycol, and the like), and suitable mixtures thereof, vegetable oils, such as olive oil, and injectable organic esters, such as ethyl oleate. Proper fluidity may be maintained, for example, by the use of coating materials, such as lecithin, by the maintenance of the required particle size in the case of dispersions, and by the use of surfactants. Further, the CD8+ T cell vaccine compositions may be encapsulated in liposomes and administered via injection.
All references cited herein are all incorporated by reference herein, in their entirety, whether specifically incorporated or not. All publications, patents, or patent applications cited herein are hereby expressly incorporated by reference for all purposes. In case of conflict, the definitions within the instant application govern.
Having now fully described this invention, it will be appreciated by those skilled in the art that the same can be performed within a wide range of equivalent parameters, concentrations, and conditions without departing from the spirit and scope of the invention and without undue experimentation.
The present description is further illustrated by the following examples, which should not be construed as limiting in any way.
Immunology Database, Los Alamos National Laboratory, http://www.hiv.lanl.gov/content/immunology/index.html) according to their HLA type. For each individual, variants that occurred at a frequency >3% were retained. Additional for PacBio reads, sequences with identified premature stop codons were eliminated from the analyzed results. For each identified variation, the mutation type regarding CTL recognition was determined by matching with the information in the above-mentioned database. The five mutation types adopted in this paper are: Documented Escape (no CTL response when patient cells are challenged with the variant peptide), Inferred Escape (variant is predicted to be an escape mutant by longitudinal study or transmission study, but the reactivity of the variant is not tested experimentally), Diminished Response (experimental data suggest partial escape as evidenced by decreased CTL response), Susceptible Form (CTL response is elicited when patient cells are challenged with the variant peptide) and Mutation Type Not Determined (no experimental data on CTL recognition of this variant).
To investigate CTL escape variants in the latent reservoir, the proviral HIV-1 DNA in resting CD4+ T cells from 25 patients was deep sequenced (Table 2). Among them, 10 initiated ART during the acute phase (AP, within 3 months of infection) while the other 15 initiated ART during the chronic phase (CP) of infection. The sequencing was focused on Gag because it is an important target of the CTL response23 and is highly conserved, which facilitates detection of escape variants. Prior data from our lab showed that previously documented CTL escape variants completely dominated the viral reservoirs of nearly all CP-treated patients (
To confirm variants detected at high frequency in the latent reservoir represent functional CTL escape mutants, cells from 7 CP-treated subjects were tested for reactivity to synthetic peptides representing wild-type and mutant versions of the relevant epitopes. As expected, there were only minimal responses to previously documented CTL escape mutants by patient CD8+ T cells, and no de novo response was detected (
Whether the host CTL response could recognize and eliminate the cells infected with these escape variants were investigated next. A ctivated CD4+ T cells from these patients were infected with autologous, replication-competent virus derived from the latent reservoir (
To further characterize which CTL population contributed to the elimination of cells infected by CTL escape variants, the killing activity of two specific CTL populations were compared: the one that targets epitopes in which escape has been identified and the one that targets unmutated epitopes (
To test whether CTL that recognize unmutated viral epitopes can inhibit HIV-1 replication and clear infected cells in vivo, patient-derived humanized mice using an improved version of a recently reported mouse system named MISTRG25 were generated. Whereas the previously reported MISTRG mice bear a BAC transgene encoding human SIRPα, the newly generated MIS(KI)TRG mice harbor a knock-in replacement of the endogenous mouse Sirpa gene with a humanized version. With humanization by knock-in replacement of the Csf1, Csf2, Il3, Tpo and Sirpa genes in the Rag2−/− Il2rg−/− genetic background, MIS(KI)TRG mice are highly permissive for human hematopoiesis and support the reconstitution of robust human lymphoid and myelomonocytic systems. With the demonstrated development of functional T-lymphocytes and monocytes/macrophages, MIS(KI)TRG mice provide a useful humanized mouse host for HIV-1 infection studies. Bone marrow biopsies were obtained from study participants and purified CD34+ cells were used to reconstitute the MIS(KI)TRG mice. These patient-derived humanized mice were infected with primary HIV-1 isolates grown from resting CD4+ T cells of the same patient and then evaluated antiviral effect of autologous CD8+ T cells (
The seeding of the HIV-1 latent reservoir starts just a few days after infection26, prior to the development of robust CTL response14. This is consistent with the finding that patients who initiated treatment early in acute infection have few if any CTL escape variants archived in the latent reservoir. However, if treatment was initiated in chronic infection, CTL escape variants became dominant in the latent reservoir, indicating a complete replacement of the initially established ‘wild-type’ reservoir. The mechanism behind this replacement warrants further investigation, but likely reflects the dynamic nature of the reservoir in untreated infection. In any event, the overwhelming presence of escape variants in the latent reservoir of chronic patients certainly presents an additional barrier to eradication efforts. The striking difference between AP- and CP-treated patients presents another argument for early treatment of HIV-1 infection; early treatment not only reduces the size of the latent reservoir27, but also alters the composition of the reservoir, as shown here, in a way that may enhance the efficacy of potential CTL-based eradication therapies.
The hierarchy of HIV-1-specific CTL response in acute infection appears to play a significant role in initial viral suppression as demonstrated by the fact that certain immunodominant CTL populations are frequently linked to lower set point viremia later in infection17,28. These immunodominant responses in acute infection have been identified as the major selection force driving the development of CTL escape mutations13, 20. Here it was shown that these immunodominant response-driven mutations are not only archived in the latent reservoir, but also in fact dominate the latent provirus population in CP-treated patients. Therefore, directing CTL responses to unmutated viral epitopes is essential to clear latent HIV-1. Due to bias in antigen presentation or recognition29, common vaccination strategies will likely re-stimulate immunodominant CTL clones which do not kill infected cells after reversal of latency. Stimulation of CTL responses with viral peptides circumvents antigen processing and is able to elicit broad-spectrum CTL responses against unmutated regions of viral proteins. These study suggests that latent HIV-1 can be eliminated in chronically infected patients despite the overwhelming presence of CTL escape variants. Future directions in therapeutic vaccine design need to focus on boosting broad CTL responses as also reported elsewhere30 and/or manipulating immuno dominance.
Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. While specific embodiments of the subject invention have been discussed, the above specification is illustrative and not restrictive. Many variations of the invention may become apparent to those skilled in the art upon review of this specification. The full scope of the invention should be determined by reference to the claims, along with their full scope of equivalents, and the specification, along with such variations. Such equivalents are intended to be encompassed by the following claims.
1Each patient's relevant optimal Gag epitopes are based: on reported information in the HIV Molecular Immunology Database, Los Alamos National Laboratory (http://www.luv.lanl.gov/content/immunology/index.html) according to the HLA type.
2Sequences from each subject were aligned to the reference HIV-1 clade B consensus Gag sequence. Variants were determined by the differences from the reference sequence.
3Mutation Type abbreviations: MTND: mutation type not determined; E: documented escape; IE: inferred escape; DR: diminished response; SF: susceptible form.
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This Application claims the benefit of U.S. Provisional Application 62/082,387, filed Nov. 20, 2014, and U.S. Provisional Application 62/091,392, filed Dec. 12, 2014, the contents of which are incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US15/61914 | 11/20/2015 | WO | 00 |
Number | Date | Country | |
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62082387 | Nov 2014 | US | |
62091392 | Dec 2014 | US |