Abstract
The generation of specific lineages of the definitive endoderm from embryonic stem (ES) cells is an important issue in developmental biology, as well as in regenerative medicine. We have established a procedure, in which M15 cells, derived from a mesonephros, are used as supporting cell line for ES cell differentiation. Under selective culture conditions, by addition of Activin and bFGF, definitive endoderm are generated from the ES cells at a high efficiency. Then, under the presence of Activin and bFGF, the differentiation into pancreatic fates is further promoted, upon the expense of the hepatic fates. On the other hand, removal of Activin, following by the addition of HGF and Dexamethasone potentiated the differentiation of ES cells into hepatic lineages. Further maturation of the pancreatic precursor could be achieved by in vivo differentiation of the differentiated ES cells. Engraftment of the cells under kidney capsule further permit the differentiation of ES cells into mature cell types containing the three pancreatic cell lineages.
