Microcolony Size Distribution Assay Enables High-Throughput Cell Survival Quantitation

Abstract

Cell survival is a critical and ubiquitous endpoint inbiology. The broadly accepted colony formationassay (CFA) directly measures a cell’s ability to divide;however, it takes weeks to perform and is incompat-ible with high-throughput screening (HTS) technolo-gies. Here, we describe the MicroColonyChip, whichexploits microwell array technology to create an arrayof colonies. Unlike the CFA, where visible coloniesare counted by eye, using fluorescence microscopy,microcolonies can be analyzed in days rather thanweeks. Using automated analysis of microcolonysize distributions, the MicroColonyChip achievescomparable sensitivity to the CFA (and greater sensi-tivity than the 2,3-bis-(2-methoxy-4-nitro-5-sulfo-phenyl)-2H-tetrazolium-5-carboxanilide [XTT] assay).Compared to CellTiter-Glo, the MicroColonyChip isas sensitive and also robust to artifacts caused bydifferences in initial cell seeding density. We demon-strate efficacy via studies of radiosensitivity andchemosensitivity and show that the approach isamenable to multiplexing. We conclude that theMicroColonyChip is a rapid and automated alternativefor cell survival quantitation.