Overview of the workflow—B cells (or enriched ASCs) are isolated from mice (bone marrow or spleen) or human PBMCs. Cells are mixed with liquid BG-agarose at 37 °C and encapsulated into picolitre water-in-oil emulsion droplets using a flow-focusing junction. Droplets are collected on ice for agarose gelation and demulsified, creating stable hydrogel beads around each cell. The BG-agarose is converted into an antibody capture matrix by the addition of recombinant capture reagents that are fused to the SNAP-tag, an enzyme that reacts with BG moieties. During incubation, antibodies secreted by a single cell are captured in the hydrogel surrounding the cell. Cells that have secreted antigen-specific antibodies are identified with fluorescently labeled detection reagents (antigens, secondary antibodies and antibodies against cell-surface markers), sorted using flow cytometry and sequenced. Antibody sequences can be obtained within 4 days, and recombinant antibodies for testing are generated in 2 weeks.
