X-ray microanalysis of epithelial cells in culture.

X-ray microanalysis of cultured cells can be used to study ion transport properties of epithelial cells in vitro. A method was developed to culture a variety of epithelial and secretory cells (colon cancer cells, insulinoma cells, sweat gland epithelium, bovine mammary epithelium). The cells were grown on Formvar-film covered titanium grids, rinsed, frozen, and freeze-dried. The cultures of colon cancer and the bovine mammary epithelial cells appeared to contain two subpopulations of cells with different elemental composition. cAMP-mediated chloride secretion could be studied in the colon cancer cells and the cultured sweat gland epithelium: the cellular content of chloride decreased after stimulation with cAMP or with substances that increase the cellular level of cAMP.