Single-Cell Droplet Microfluidic Screening for Antibodies Specifically Binding to Target Cells

Abstract

SummaryMonoclonal antibodies are a main player in modern drug discovery. Many antibody screening formats exist, each with specific advantages and limitations. Nonetheless, it remains challenging to screen antibodies for the binding of cell-surface receptors (the most important class of all drug targets) or for the binding to target cells rather than purified proteins. Here, we present a high-throughput droplet microfluidics approach employing dual-color normalized fluorescence readout to detect antibody binding. This enables us to obtain quantitative data on target cell recognition, using as little as 33 fg of IgG per assay. Starting with an excess of hybridoma cells releasing unspecific antibodies, individual clones secreting specific binders (of target cells co-encapsulated into droplets) could be enriched 220-fold after sorting 80,000 clones in a single experiment. This opens the way for therapeutic antibody discovery, especially since the single-cell approach is in principle also applicable to primary human plasma cells.

Exploiting B Cell Receptor Analyses to Inform on HIV-1 Vaccination Strategies

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“…However, the native pairing information of heavy and light chains is essential to fully describe an individual antibody, e.g., for recombinant expression. Although pairing information can be restored to some extent from bulk analyses (i.e., by bioinformatic approaches) [56], the most robust way to achieve these information is either by single cell sorting into multi-well plates [57][58][59][60] or by co-encapsulation of single cells and RNA-capture or barcode beads (e.g., with the 10× Genomics chromium system) in picoliter droplets [23,24,[61][62][63][64][65] (Figure 3, second row). Single cell sorting into multiwell plates is typically limited in throughput to tens of thousands of cells, whereas encapsulation systems allow throughputs of hundreds of thousands of cells.…”

Deep learning guided image-based droplet sorting for on-demand selection and analysis of single cells and 3D cell cultures

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Establishment of a novel method for the production of chimeric mouse embryos using oil droplets

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