Functional screening of antibody-secreting cells by co-culture with reporter T cells using PicoShells.

Monoclonal antibodies (mAbs) are a growing class of therapeutics known for their high specificity and diverse functional mechanisms, including agonism and antagonism. Although microwell array technologies and droplet microfluidics are employed to pair antibody-secreting cells (ASCs) with target cells for therapeutic mAb discovery, existing methods suffer from limited throughput or inadequate functional assessment. To address these limitations, we applied PicoShells, hollow media-permeable hydrogel microparticles, to evaluate mAb function by co-culturing hybridomas with reporter cells for 24 hours. Using this workflow, we identified hybridomas secreting antibodies that modulate the expression of nuclear factor of activated T cells (NFAT) in co-encapsulated reporter cells. High-throughput fluorescence activated cell sorting (FACS) of PicoShells containing cells from a spiked population identified active clones, which were sorted, expanded, and validated post-selection, demonstrating 79.4% T cell activation, a 5.2-fold enrichment in functional clones over the starting spiked population. This approach integrates functional assessment with scalable processing, offering a robust solution for screening antibody libraries and accelerating therapeutic discovery.