Culture pH and osmolality influence proliferation and embryoid body yields of murine embryonic stem cells

Abstract The realization of many stem cell based regenerative therapies will depend on culture production. Murine embryonic stem cells (mESC) provide a practical model for stem cell process research as they can be readily obtained at relatively high numbers and purities. However, an understanding of their environmental tolerance ranges is still lacking. These tolerance ranges were explored using an embryoid body (EB) formation assay as a functional measure of mESC maintenance. The mESC were exposed to wide ranges of initial medium glucose, glutamine, ammonium, lactate, pH and osmolality conditions. Within the common ranges of conventional maintenance cultures, the only environmental variables that significantly influenced EB yields were pH and osmolality. Dose–response experiments with these two variables revealed that, within 48 h, the EB yield was, for example, ∼3-fold decreased ( p