Culture Conditions for Mouse Pancreatic Stem Cells.

Recently, mouse pancreatic stem cells have been isolated from adult mouse pancreata. However, these pancreatic stem cells could be maintained only under specific culture conditions with lot-limited fetal bovine serum (FBS). For the efficient isolation and maintenance of mouse pancreatic stem cells, it is important to identify culture conditions that can be used independent of the FBS lot. In this study, we evaluated the culture conditions required to maintain mouse pancreatic stem cells. The mouse pancreatic stem cells derived from the pancreas of a newborn mouse, HN#101, were cultured under the following conditions: 1) Dulbecco's modified Eagle's medium (DMEM) with 20% lot-limited FBS, in which mouse pancreatic stem cells could be cultured without changes in morphology and growth activity; 2) complete embryonic stem (ES) cell media; and 3) complete ES cell media on feeder layers of mitomycin C-treated STO cells, which were the same culture conditions used for mouse ES cells. Under culture conditions #1 and #3, the HN#101 cells continued to form a flat "cobblestone" monolayer and continued to divide actively beyond the population doubling level (PDL) 100 without growth inhibition, but this did not occur under culture condition #2. The gene expression profile and differentiated capacity of the HN#101 cells cultured for 2 months under culture condition #3 were similar to those of HN#101 cells at PDL 50. These data suggest that complete ES cell media on feeder layers could be useful for maintaining the undifferentiated state of pancreatic stem cells.