The present invention is in the field of biochemical analysis and provides assay plates, plate arrays and assemblies including recovery funnels for recovery of samples from reservoirs on the assay plates.
Single-cell studies have become more prominent in recent years in fields such as stem cell biology, hematology, cancer biology and tissue engineering. Measuring cells in populations involves analysis of average signals from a large number of cells. It is highly challenging to analyze cell types constituting a minority in such samples because their properties are hidden by the majority population. Thus, an appropriate analysis of samples with significant cellular heterogeneity is ideally performed on a single-cell level. Many applications in drug discovery or medical diagnostics, such as single-cell microarrays, single-cell PCR, isolation of rare cells, or production of clonal cell lines, could benefit significantly from analytical approaches based on single cells.
In practice, separation and manipulation of individual living biological cells remains a challenging task in many life science applications. At present, the commercially available technologies to separate single cells from a suspension and deposit them individually on substrates are quite rare, especially regarding processing of nontreated samples and label-free cells (Gross et al. J. Lab. Automation 2013, 18(6), 504-518, incorporated herein by reference in its entirety).
Technologies for single-cell isolation, e. g. for handling of single cells in biotechnology and medicine, include flow cytometry, manual cell picking, microfluidic techniques, and inkjet-like single-cell printing. In general terms, a single-cell printer isolates a single cell and places it in a receptacle having a micro- or nano-scale volume wherein a subsequent assay is conducted. A single-cell printer typically comprises a microfluidic dispenser integrated in a polymer cartridge. Droplets of a cell suspension included in the dispenser are deposited in a receptacle on a target substrate. Single-cell printing has advantages in terms of flexibility and easy interfacing with other upstream and downstream methods. However, single-cell printers have to be controlled such that each droplet deposited onto the target includes one single cell only (Gross et al. Int. J. Mol Sci. 2015, 16, 16897-16919, incorporated herein by reference in its entirety).
Examples of single cell printing are described and claimed in commonly owned European Patent Application Publication No. EP3222353 and European Patent Application No. EP17189875, each of which are incorporated herein by reference in entirety.
There continues to be a need for development of technologies for single cell isolation and manipulation.
One aspect of the invention is an assay plate which includes a body having a plurality of reservoirs formed therein. The reservoirs are shaped and aligned in the body in an orientation to induce drainage of fluids contained therein in a desired direction. The desired direction may be towards a single plane or a single point.
In some embodiments, the reservoirs each have a spout portion which has a vertex directed toward the single plane or the single point.
The reservoirs may be provided with a downwardly tapered frustoconical portion adjacent to the spout portion. The frustoconical portion may have a frustrum forming the base of the reservoir.
The reservoirs may have a boundary between the frustoconical portion and the spout portion defined by a pair of opposed transition planes each intersecting an inner sidewall of the reservoir at distances equidistant from the vertex such that a connectivity plane located between the vertex and the center of the base divides the spout into symmetric halves. In such embodiments, a first angle between a first perpendicular reference plane intersecting the edge of the base closest to the vertex and the connectivity plane is greater than a second angle between a second perpendicular reference plane intersecting the edge of the base in the frustoconical portion and an interior sidewall of the frustoconical portion.
The reservoir may have a teardrop-shaped upper edge and the base may be circular or teardrop shaped.
In some embodiments, the spout includes a ledge portion, wherein a third angle between the first perpendicular reference plane and the connectivity plane on the ledge portion is greater than the first angle between the first perpendicular reference plane intersecting the edge of the base closest to the vertex and the connectivity plane.
In some embodiments, the body of the plate array may be rectangular and provided with a downward slope from a single elevated corner, wherein the desired direction of the drainage of fluids is towards the corner opposite the elevated corner. In other embodiments, the body may be rectangular with a level upper surface.
In some embodiments, the plurality of reservoirs is 96 reservoirs.
In some embodiments, the reservoirs have volumes of less than about 200 nanoliters.
Another aspect of the invention is a plate array comprising a plurality of assay plates of the embodiments described hereinabove. In one embodiment, the plurality of assay plates is four plates.
Another aspect of the invention is assembly for pooling assay samples contained in reservoirs of plate arrays. The assembly may include a rectangular plate array as described hereinabove and a rectangular funnel array comprising a plurality of rectangular funnels, each configured for connection to a single plate of the plurality of plates.
Each of the rectangular funnels of the funnel array may have a collecting vessel located closer to one funnel corner such that when the funnel array is connected to the plate array, the desired direction of drainage of fluids from each plate of the plurality of rectangular plates is towards the collecting vessel of the connected funnel.
The corners of the plate array may be shaped to accept the corners of the funnel array in only a single orientation, thereby ensuring that the desired direction of drainage of fluids is towards the collecting vessel.
A transverse channel may be provided between adjacent plates of the plate array.
The assembly may also include a housing for coupling the assembly to a rotor of a centrifuge.
Another aspect of the invention is a kit for conducting an assay. The kit includes a plate array as described hereinabove, a rectangular funnel array comprising a plurality of rectangular funnels, each configured for connection to a single plate of the plurality of plates, and instructions for connecting the funnel array to the plate array for draining fluids from the reservoirs of the plate array via centrifugation.
The kit may also include a housing for retaining the plate array and funnel array in a connected arrangement in a centrifuge.
In some embodiments of the kit, the collecting vessels are attached to or formed integrally with the funnels of the funnel array.
The kit may also include a frame configured to hold the plate array during dispensing of components into the reservoirs during preparation of the assay.
In some embodiments of the kit, each one of the reservoirs includes an identifier for identifying each one of the reservoirs during the assay. The identifier may be a nucleic acid molecule, protein, glycan, peptide, aptamer, small molecule, nanoparticle, or a heavy metal with an isotope which is identifiable by mass spectrometry. Other analytical techniques may be used to confirm the presence of the identifier.
The kit may also include reagents for the assay provided in individual vessels.
In some embodiments of the kit, the assay is a sequencing assay, a gene expression assay or a protein expression assay.
The details of various embodiments of the disclosure are set forth in the description below. Other features, objects, and advantages of the disclosure will be apparent from the description, drawings, and the claims. In the description, the singular forms also include the plural unless the context clearly dictates otherwise. 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 disclosure belongs. In the case of conflict, the present description will control.
The foregoing and other objects, features and advantages will be apparent from the following description of particular embodiments of the disclosure, as illustrated in the accompanying drawings. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of various embodiments of the disclosure.
The present inventors, being engaged in development of nanoscale devices and instrumentation for processing biomolecules and printing single cells have made a number of technological advances in single cell printing devices, such as for example, the devices described and claimed in commonly owned European Patent Application Publication No. EP3222353 and European Patent Application No. EP17189875 (each incorporated herein by reference in entirety). Such advances are expected to lead to development of additional efficiencies in a number of nano-scale assays such as various different types next generation sequencing, gene expression analyses and proteomics analyses of single cells. In the process of customization of various assays, the inventors have recognized certain shortcomings in conventional sample plates designed for use with samples at the nano-scale level. At the nano-scale, capillary action is an important contributor in determining flow of fluids into and out of sample reservoirs. In particular, problems arise during sequential dispensing of various reagents into such nano-scale reservoirs, which may prevent the desired mixing. For example, the inventors have discovered that dispensing of picoliter volumes into conventional nano-scale reservoirs will occasionally and consistently result in ejection of fluids from such reservoirs. This is a problematic occurrence because it will result in cross-contamination between reservoirs of a plate. Development of the shaped reservoirs described herein has been found effective in addressing this problem.
In addition, the same issues arise when removing samples from such reservoirs in situations where sample pooling is desired. The inventors have discovered that providing plate reservoirs which are individually shaped and aligned with each other will improve the flow of fluids into and out of the individual reservoir. This provides significant advantages in processing of samples at the nanoscale level. The advantages provided by the embodiments described herein are expected to be applicable to essentially any assay requiring dispensation of single cells, biomolecules, fluids, particles, reagents and solutions at the micro-, nano-, and pico-scale level.
The details of embodiments of the invention are set forth in the accompanying description below. Although any materials and methods similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred materials and methods are now described. Other features, objects and advantages of the invention will be apparent from the description. In the description, the singular forms also include the plural unless the context clearly dictates otherwise. 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. In the case of conflict, the present description will control. A number of alternative features will be introduced during the course of describing various embodiments. Such alternative features may be combined to produce specific combinations which may not be described explicitly herein. Nonetheless, such alternative embodiments are within the scope of the invention. In the description below, similar reference numerals are used as identifiers of similar features in most cases.
Turning now to
Additional features of the plate array 100 include frame channels 132 formed in the frame 130 between the plates and a recess 125 partly surrounding each plate. Thus, at the elevated corners 126 of each plate, the recess 125 is absent but as each plate slopes downward, it transitions to becoming partially circumscribed by the recess 125. As seen in
The recess 125 provides structure for connection of a recovery funnel (not shown) having a complementary recess-coupling ridge-like structure to facilitate drainage of the contents of the reservoir 140. An alternative embodiment described hereinbelow will be used to highlight the features of an array of recovery funnels.
It is to be noted that each of the reservoirs 140 is teardrop-shaped. All of these reservoirs are aligned with the teardrop vertex pointing away from the elevated corner 126 of each plate and towards the opposite corner. When the contents of the reservoirs are being removed by centrifugation, liquids are induced to drain into a recovery funnel in a direction opposite the elevated corner, exiting each reservoir at the vertex.
Turning now to
In plate array 200, the reservoirs 240 are also teardrop shaped. In the top views of four reservoirs 240 in
This pitcher-shaped reservoir 240 is defined by having a sidewall 242 with a slope transitioning from a steeper slope to more gradual slope at the spout portion 248 as shown in
This pitcher-shaped reservoir 240 has been found to be an effective reservoir shape to provide improvements in processes for dispensing fluids into the reservoir 240 and removal of sample fluids contained therein.
Turning now to
Functionally, this reservoir embodiment 340 differs from reservoir embodiment 240 in providing a more readily predictable flow pattern as a result of having a base with a uniformly circular base as well as being more reliably formed by 3D-printing or hot embossing. Alternative embodiments have bases with different shapes and dimensions. It is expected that a reservoir with a base having a reduced base surface area will provide certain advantages, such as functionality in concentration of fluids.
In
The frame 363 of the funnel array 360 includes three transverse dividers 367a-c (best seen in
It is seen in
In this embodiment, each funnel 361a-d has an upper portion with a relatively narrow vertical sidewall 365a-d which engages the side edges 332a-d of the plates 350a-d when the funnel array 360 is connected to the plate array 300. This provides an additional press-fit frictional engagement coupling mechanism to connect the funnel array 360 to the plate array 300.
The funnel array 360 has funnels 361a and 361d with rounded corners 368a, 368a′, 368d, and 368d′ to fit the corners of end plates 350a and 350d of the plate array 300. In this embodiment, the rounded corners are substantially similar. However, an alternative embodiment (not shown) of the funnel array 360 and plate array 300 assembly has a single uniquely-shaped corner at any one of the four locations in the funnel array 360 and in the plate array 300. This will ensure that connection of the funnel array 360 to the plate array 300 will be made in a proper orientation with the vertices and spouts of the reservoirs 340 of each plate 350a-d being directed towards the corner closest to the outlet of each connected funnel 361a-d of the funnel array 360. This alternative embodiment is particularly advantageous because the reservoirs 340 of the plate array 300 are small and it is challenging to identify the vertices and spouts of the reservoirs in order to ensure that they point towards the outlets 362a-d of the funnel array 360. The single set of unique corner couplings would prevent the funnel array 360 from being connected to the plate array 300 in an incorrect orientation where the vertices and spouts of the reservoirs 340 on the plate array 300 point away from the outlets 362a-d of the funnels 361a-d, as an attempt to make such a connection would fail as a result of incorrect matching of complementary corners on the plate array 300 and the funnel array 360. In an alternative embodiment, instead of providing a single set of uniquely matched corners, a visual indicator such as matched marking signs on the funnel array 360 and plate array 300 could be provided to instruct a user to connect the funnel array 360 to the plate array 300 in the proper orientation.
As noted above,
Collecting vessels 370a-d are connected to the outlets 361a-d of the funnel array 360. This assembly is placed in a separate housing (not shown) designed to rigidly retain the assembly within a centrifuge such that during centrifugation, with the plate array 300 placed upside down, fluids contained within each reservoir 340 are induced to flow out of the reservoir 340 via the spout 348, through the respective funnels 361a-d and outlets 362a-d and into the collecting vessels 370a-d. It is to be understood that all 96 wells of each plate 350a-d will be pooled together into respective collecting vessels 370a-d. Therefore, it is possible to conduct an experiment with four separate conditions or sample components in the four separate plates.
Referring now to
Turning now to
A reagent R-1 is dispensed from a dispenser into the reservoir 240 containing the molecular identifier and lands onto the spout side of the reservoir 240 where the reagent is held by capillary force adhesion. In the next step (which would occur after dispensing the reagent into additional reservoirs 240), the array plate 200 is placed in a centrifuge housing (not shown) and centrifuged to move the reagent to the base of the reservoir 240. In the next step (
Turning now to
Referring now to
Turning now to
The massive parallelization of biological assays and realization of single-molecule resolution have yielded profound advances in the ways that biological systems are characterized and monitored and the way in which biological disorders are treated. Assays are used to interrogate thousands of individual molecules simultaneously, often in real time. These biochemical and medical assays often rely on the accurate and precise positioning of individual assay components on a molecular scale. Thousands of nanoscale assays are often patterned on a substrate for macro-manipulation, analysis, and data recording.
The combination of solid-state electronics technologies to biological research applications has provided a number of important advances including DNA arrays (see, e.g., U.S. Pat. No. 6,261,776, incorporated herein by reference in its entirety), microfluidic chip technologies (see e.g., U.S. Pat. No. 5,976,336, incorporated herein by reference in its entirety), chemically sensitive field effect transistors (ChemFETs), and other valuable sensor technologies.
Next generation sequencing methods are often conducted as nano-scale assays and involve complex reaction mixtures. Examples of such next generation sequencing methods include, but are not limited to, single-molecule real-time sequencing (Pacific Biosciences), ion semiconductor sequencing (ion torrent sequencing), pyrosequencing, sequencing by synthesis (Illumina), Combinatorial probe anchor synthesis (cPAS-BGI/MGI), sequencing by ligation (SOLiD sequencing), nanopore sequencing, and chain termination (Sanger sequencing).
Proteomics assays are also conducted as nano-scale assays and may include analyses and equipment such as antibody-based detection, mass spectrometry, protein chips, and reverse-phased protein microarrays. Proteomics assays are used in applications such as drug discovery, establishment of protein interactions and networks, protein expression profiling, identification of biomarkers, proteogenomics and structural proteomics.
Any or all of the applications described above may benefit from the use of plate arrays such as the plate arrays described herein.
Certain aspects of the invention include provision of kits for conducting nano-scale assays. Various embodiments of such kits include a plate array including a plurality of plates supported on a platform, such as the plate arrays 100, 200, 300 or 400 described herein or other plates having reservoirs with at least some of the reservoir features described herein. In some embodiments, the plate array includes a molecular identifier contained within each reservoir of each plate of the plate array. In some embodiments, the kit also includes a recovery funnel array with a funnel for each plate. In some embodiments, the funnels are provided as a connected array with a matched funnel for each plate of the plate array to facilitate a process for generating a pooled sample from individual samples contained within individual reservoirs on a plate of the plate array. In some embodiments, the kit includes collection vessels configured to be coupled to the funnel outlets for collection and retention of a pooled sample. In some embodiments, there is provided a kit with a plate array, a funnel array with a series of connected funnels matched to each plate of the plate array, collection vessels and a series of reagents for performing an assay. Some kit embodiments further include a plate array housing configured for connection to a centrifuge to promote sample collection. Other kit embodiments further include a plate array holder configured to be connected to a specific dispensing device. Example embodiments of kits include, but are not limited to kits for performing single cell RNA sequencing, single cell whole genome amplification, and single cell proteomics by mass spectrometry.
Unless stated otherwise, the following terms and phrases have the meanings described below. The definitions are not meant to be limiting in nature and serve to provide a clearer understanding of certain aspects of the present disclosure.
About: As used herein, the term “about” means+/−10% of the recited value.
Approximately: As used herein, the term “approximately” or “about,” as applied to one or more values of interest, refers to a value that is similar to a stated reference value. In certain embodiments, the term “approximately” or “about” refers to a range of values that fall within 25%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or less in either direction (greater than or less than) of the stated reference value unless otherwise stated or otherwise evident from the context (except where such number would exceed 100% of a possible value).
Feature: As used herein, a “feature” refers to a characteristic, a property, or a distinctive element.
Sample: As used herein, the term “sample” or “biological sample” refers to a subset of its tissues, cells or component parts (e.g. body fluids, including but not limited to blood, mucus, lymphatic fluid, synovial fluid, cerebrospinal fluid, saliva, amniotic fluid, amniotic cord blood, urine, vaginal fluid and semen). A sample further may include a homogenate, lysate or extract prepared from a whole organism or a subset of its tissues, cells or component parts, or a fraction or portion thereof, including but not limited to, for example, plasma, serum, spinal fluid, lymph fluid, the external sections of the skin, respiratory, intestinal, and genitourinary tracts, tears, saliva, milk, blood cells, tumors, organs. A sample further refers to a medium, such as a nutrient broth or gel, which may contain cellular components, such as proteins or nucleic acid molecule.
Substantially: As used herein, the term “substantially” refers to the qualitative condition of exhibiting total or near-total extent or degree of a characteristic or property of interest. One of ordinary skill in the biological arts will understand that biological and chemical phenomena rarely, if ever, go to completion and/or proceed to completeness or achieve or avoid an absolute result. The term “substantially” is therefore used herein to capture the potential lack of completeness inherent in many biological and chemical phenomena.
Substantially equal: As used herein as it relates to time differences between doses, the term means plus/minus 2%.
Substantially simultaneously: As used herein means within about 0.5 to about 2 seconds.
Tapered: As used herein, means becoming diminished in thickness or width toward one end.
Ledge: As used herein, means a surface being closer to horizontal than adjacent surfaces.
Frustoconical: As used herein, means a truncated conical shape.
Frustrum: As used herein, means a circular shape formed by the plane cutting off the vertex to generate a frustoconical shape.
Array: As used herein, means an ordered series or arrangement.
Reservoir: As used herein, means a cavity designed for retention of fluids.
Assay: As used herein, means an experimental test.
Spout: As used herein, means an extension or lip configured to induce flow of fluids out of a reservoir.
Plane: As used herein, means a flat surface. Any two points on a plane would be connected by a straight line.
Plane of connectivity: As used herein means a plane where two geometric shapes connect to each other.
Transition plane: As used herein, means a plane passing through a surface where the surface transitions from one shape to another shape.
Vertex: As used herein, means the angular point of a geometric shape.
Those skilled in the art will recognize or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments in accordance with the disclosure herein. The scope of the present disclosure is not intended to be limited to the above Description, but rather is as set forth in the appended claims.
In the claims, articles such as “a,” “an,” and “the” may mean one or more than one unless indicated to the contrary or otherwise evident from the context. Claims or descriptions that include “or” between one or more members of a group are considered satisfied if one, more than one, or all of the group members are present in, employed in, or otherwise relevant to a given product or process unless indicated to the contrary or otherwise evident from the context. The disclosure includes embodiments in which exactly one member of the group is present in, employed in, or otherwise relevant to a given product or process. The disclosure includes embodiments in which more than one, or the entire group members are present in, employed in, or otherwise relevant to a given product or process.
It is also noted that the term “comprising” is intended to be open and permits but does not require the inclusion of additional elements or steps. When the term “comprising” is used herein, the term “consisting of” is thus also encompassed and disclosed.
Where ranges are given, endpoints are included. Furthermore, it is to be understood that unless otherwise indicated or otherwise evident from the context and understanding of one of ordinary skill in the art, values that are expressed as ranges can assume any specific value or subrange within the stated ranges in different embodiments of the disclosure, to the tenth of the unit of the lower limit of the range, unless the context clearly dictates otherwise.
In addition, it is to be understood that any particular embodiment of the present disclosure that falls within the prior art may be explicitly excluded from any one or more of the claims. Since such embodiments are deemed to be known to one of ordinary skill in the art, they may be excluded even if the exclusion is not set forth explicitly herein. Any particular embodiment of the compositions of the disclosure (e.g., any antibiotic, therapeutic or active ingredient; any method of production; any method of use; etc.) can be excluded from any one or more claims, for any reason, whether or not related to the existence of prior art.
It is to be understood that the words which have been used are words of description rather than limitation, and that changes may be made within the purview of the appended claims without departing from the true scope and spirit of the disclosure in its broader aspects.
While the present disclosure has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with references to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the disclosure.
All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety. In case of conflict, the present specification, including definitions, will control. In addition, section headings, the materials, methods, and examples are illustrative only and not intended to be limiting.
This application claims priority to U.S. 62/844,965 filed May 8, 2019, entitled Assay Plate with Nano-Vessels and Sample Recovery Assembly, the contents of which are herein incorporated by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2020/062868 | 5/8/2020 | WO | 00 |
Number | Date | Country | |
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62844965 | May 2019 | US |