Spatial transcriptomics in pips
This disclosure provides methods and systems for single-cell, multi-omic analysis of target cells without microfluidic devices. The disclosed methods involve the use of template particles to template the formation of monodisperse droplets to generally capture a single target cell from a population of cells in an encapsulation, derive a plurality of distinct mRNA molecules from the single target cell, and quantify the distinct mRNA molecules to generate an expression profile. Nucleic-acid-tagged antibody conjugates are used for simultaneous proteomic analysis along with the gene expression profiling.
1 . A method for gene expression profiling, the method comprising:
incubating a tissue sample on an array comprising a plurality of labels having binding specificity for a cellular protein and having a nucleic acid index identifying the location of the label on the array, wherein the labels are lyophilized and released upon wetting of the array;
disaggregating a plurality of cells from the tissue sample;
combining the disaggregated plurality of cells with template particles; and
generating a plurality of uniform partitions substantially instantly that encapsulate a single one of the template particles and a single one of the disaggregated cells to form pre-templated instant partitions (PIPs); and
releasing in each PIP nucleic acid molecules and proteins from the disaggregated cells, including proteins bound by a label from the array.
2 . The method of claim 1 , wherein the labels comprise a DNA-conjugated antibody or fragment, a DNA-conjugated aptamer, or a DNA-conjugated lipid.
3 . The method of claim 1 , wherein the step of releasing nucleic acid molecules from the cells comprises releasing RNA molecules.
4 . The method of claim 3 , wherein each of the nucleic acid molecules and labels released from a cell in each PIP is provided a nucleic acid barcode unique to the PIP.
5 . The method of claim 4 , wherein each of the nucleic acid molecules is provided with a unique molecular barcode.
6 . The method of claim 5 , wherein the step of providing a nucleic acid barcode unique to the PIP and a unique molecular identifier comprises the step of reverse transcribing RNA molecules to form cDNA complements comprising the unique molecular identifier and barcode unique to the PIP.
7 . The method of claim 6 , further comprising the step of sequencing the cDNA complements to generate sequence reads associated with each RNA molecule.
8 . The method of claim 7 , further comprising the step of associating each label from a PIP with each sequence read associated with an RNA molecule from the same PIP to generate a set of sequence reads for each label.
9 . The method of claim 1 , wherein the step of incubating the tissue sample comprises:
i) permeabilizing the tissue sample;
ii) staining the tissue sample; and/or
iii) imaging the tissue sample.
10 . The method of claim 1 , wherein the labels have specificity for a nuclear envelope cell protein, disaggregated proteins, or nuclear proteins.
11 . The method of claim 1 , wherein each index identifies at least the X and/or Y coordinates of the label on the array.
12 . The method of claim 11 , wherein each location on the array comprises at least two labels together identifying the X and Y coordinates of the location on the array.
13 . The method of claim 1 , wherein the array is a glass array.
14 . The method of claim 13 , wherein the labels are spotted onto the glass array.
15 . The method of claim 13 , wherein the labels are covalently bonded to the glass array.
16 . The method of claim 14 , wherein the labels are covalently bonded to the glass array by siloxane chemistry.
17 . The method of claim 16 , wherein the labels are covalently bonded to the glass array by their index.
18 . The method of claim 17 , wherein the index comprises a moiety for controlled release of label.
19 . The method of claim 1 , wherein:
the step of combining the template particles with the plurality of disaggregated cells comprises combining the particles and cells in a first fluid and adding a second fluid to the first fluid, wherein the first fluid and second fluid are immiscible;
the step of generating a plurality of uniform partitions near-instantly comprises: agitating the fluids to generate the PIPs that contain a single one of the template particles and a single one of the disaggregated cells; and/or
the step of releasing in each PIP nucleic acid molecules from the cells comprises: lysing each of the single cells contained within the PIPs.
20 . The method claim 19 , wherein the step of combining cells and template particles and the step of generating a plurality of uniform partitions near-instantly are performed in a tube, wherein the tube is a centrifuge, microcentrifuge, or polymerase chain reaction (PCR) tube.
21 . The method of claim 20 , wherein the step of generating in the tube a plurality of uniform partitions near-instantly that encapsulate a single one of the template particles and a single one of the cells comprises generating a plurality of partitions that encapsulate a single one of the template particles and do not encapsulate a cell.