[Human amnion cells express the phenotypes of neural cells and adipocytes in vitro]

To search for culture conditions in which the cells from human amnion could diferentiate into neural cells and hence to explore a new cell source for neural transplantaion.

Amnion cells from human were cultured with tissue piece method, passaged by trypsin digestion and identified with immunocytochemistry.

Amnion cells migrated from explants and primary culture was established; they could multiply and expand steadily in a short time, and they could be passaged by trypsin digestion. When cultured in serum-free neural stem cell media, these cells could form the same spheroid shape as the neurospheres of neural stem cells. They could express alpha smooth muscle actin and differentiate into smooth muscle cells spontaneously, and could express nestin and vimentin, the markers for neural progenitors. Moreover, they could he stained by anti-beta III-tubulin, anti-neurofilament 200 and anti-NSE; the majorities could he stained by antityrosine hydroxylase, the marker for dopaminergic neurons. Lower than 0.1% of the total cells were stained by GFAP, indicating the existence of astrocytes. The amnion cells could also differentiate into adipocytes under specific induction.

Amnion cells could differentiate into adipocytes and smooth muscle cells; they could express the protein for neural cells; thus may represent an alternative stem cell source for CNS cell transplantation.