title: Characterization and practical benefits of keratinocytes cultured in strontium-containing serum-free medium.
abstract: Strontium (Sr2+) can substitute for Ca2+ and stimulate a variety of functions of numerous types of cells. The purpose of this study was to investigate the details of the biologic effects of Sr2+ on human keratinocyte growth, cell cycle, viability, and differentiation and to compare these effects with Sr2+ effects on cultured skin melanocytes. Cultured keratinocytes stimulated with 1.0-3.0 mM Sr2+ showed higher viability and almost a twofold increase in cell number compared with those grown in a standard calcium concentration. Time course studies revealed that 2.0 mM Sr2+ had no effects on growth of cultured melanocytes or fibroblasts. Sr2+ increased the percentage of cultured keratinocytes in G2/M phase, with a decrease in cells in G0/G1 phase. This effect of Sr2+ on the cell cycle was not seen in cultured melanocytes or fibroblasts. A 2 mM concentration of Sr2+ produced an increase in low-density keratinocytes separated by a Percoll gradient. In addition, increased expression of human fibronectin was observed in the cytoplasm and on cell membranes of keratinocytes cultured in Sr2+. Sr2+ can be of practical benefit in the culture of human keratinocytes in serum-free medium, increasing the viability and proliferative rate and producing a more uniform population of basaloid cells with increased expression of cell surface fibronectin.
mesh_terms: D002452:Cell Count / Q000187:drug effects; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003470:Culture Media; D003584:Cytological Techniques / Q000592:standards*; D000078404:Epidermal Cells; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D005455:Fluorescent Antibody Technique; D006801:Humans; D007633:Keratins; D008544:Melanocytes / Q000166:cytology / Q000187:drug effects; D013324:Strontium / Q000494:pharmacology*
chemical_list: D003470:Culture Media; D007633:Keratins; D013324:Strontium