Methods, compositions, and systems for identifying antigen-binding molecules

A method of identifying an antigen-binding molecule that selectively binds to an antigen in a biological sample, the method comprising:

• a) providing an array comprising a plurality of capture probes, wherein a capture probe of the plurality of capture probes comprises:
• (i) a spatial barcode and (ii) a capture domain;
• b) contacting the biological sample with members of an antigen-binding molecule/nucleic acid conjugate library, wherein an antigen-binding molecule/nucleic acid conjugate of the library comprises an antigen-binding molecule linked to a nucleic acid encoding the antigen-binding molecule, and wherein the nucleic acid comprises a cDNA/RNA duplex, wherein the RNA of the cDNA/RNA duplex comprises:
• i) a sequence complementary to an analyte capture sequence which hybridizes to the capture domain of the capture probe,
• ii) a sequence encoding an antigen-binding molecule,
• iii) a primer binding sequence, and
• iv) a universal domain attached to a donor oligonucleotide, wherein the donor oligonucleotide comprises a linker having a nucleotide sequence and a protein translation inhibitor;
• c) hybridizing the analyte capture sequence of one or more cDNAs of the antigen-binding molecule/nucleic acid conjugates with the capture domain of the capture probe on the array;
• and
• d) determining (i) the sequence of the spatial barcode or a complement thereof, and (ii) all or a portion of the sequence of the cDNA, or a complement thereof and using the determined sequences of (i) and (ii) to identify an antigen-binding molecule that selectively binds to an antigen in the biological sample.