Massively parallel encapsulation of single cells with structured microparticles and secretion-based flow sorting

Techniques to analyze and sort single cells based on secreted products have the potential to transform our understanding of cellular biology as well as accelerate the development of next generation cell and antibody therapies. However, secretions are rapidly transported away from cells, such that specialized equipment and expertise has been required to compartmentalize cells and capture their secretions. Herein we demonstrate the use of cavity-containing hydrogel microparticles to perform functional single-cell secretion analysis and sorting using only commonly accessible lab infrastructure. These microparticles act as a solid support which facilitates cell attachment, templates formation of uniform aqueous compartments which prevent cross-talk between cells, and captures secreted proteins. Using this platform we demonstrate high-throughput analysis and sorting of Chinese Hamster Ovary cells based on their relative production of human IgG using commercially available flow sorters. Microparticles are easily distributed and used, democratizing access to high-throughput functional cell screening.