Rapid Clonal Growth Measurements at the Single-Cell Level: Gel Microdroplets and Flow Cytometry

Abstract

We describe a new, general method for rapidly measuring clonal growth of large numbers of individual members of a cell population. This method is based on microculture of individual colony-forming units in gel microdrops (GMDs; here aga-rose; 20 to 90μ in diameter), which are sufficiently robust to be handled much like cells, and diffusionally transparent for molecules of interest. Flow cytometry provides rapid measurements of GMD-entrapped microcolonies, and permits sub-population analysis. Here the method is demonstrated with mammalian, fungal and bacterial species. Additional results illustrate rapid determination of a drug-resistant subpopulation in a mixed species sample, and nutrient sensitivity for a murine hybridoma.