Activin promotes astrocytic differentiation of a multipotent neural stem cell line and an astrocyte progenitor cell line from murine central nervous system.

The effects of activin A were investigated on the development of a multipotent neural stem cell line (MEB5) and an astrocyte progenitor cell line (AP-16) that were established from murine central nervous system (CNS). Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis demonstrated that each cell line expresses both type I and type II activin receptors and signaling molecules for activin, Smad2, Smad3, and Smad4. Activin A did not affect the proliferation of MEB5 and AP-16 cells. When each cell line was treated alone with activin A, glial fibrillary acidic protein (GFAP), a marker for astrocytes, was induced in AP-16 cells, but not in MEB5 cells. However, activin A accelerated the leukemia inhibitory factor (LIF)-induced astroglial differentiation of MEB5 cells. These results suggest that activin promotes astrocyte differentiation of CNS neural progenitors, and the competence to activin is different between multipotent stem cells and unipotent astrocyte progenitor cells.