Antigen Specific Lysis: High Throughput, High Purity Cell Sorting Through Polymer Design

High purity cell sorting is at the core of many basic and applied clinical research studies. Current approaches including fluorescence-activated cell sorting (FACS) and magnetic-activated cell sorting (MACS) are limited by low throughput and low specificity, respectively. A faster, high purity method of cell isolation would improve the quality and rate of downstream biological investigations.

Here, we describe a novel approach for high throughput cell isolation based the specific protection of targeted cells and the lysis of nonspecific species.  Briefly, antibody affinity directs the localization of a photoinitiator on the surface of targeted cells, the cells are immersed in monomer solution, and visible light induces cross-linking of poly(ethylene glycol) diacrylate (Mn=575) exclusively around target cells. Upon rinsing, the antigen-positive cells are now encapsulated by a crosslinked polymer film, where antigen-negative cells are unprotected.  The entire population is then exposed to lysis agents  (surfactants, proteases, hypotonic solutions, etc.) to lyse unprotected cells. Our initial results show encapsulated cells are >75% viable, where unprotected cells are >99.5% dead. We describe in detail the structure and behavior of the protective polymer and relate these characteristics to the exclusion of macromolecules and lysing agents.