Human Amniotic Epithelial Cells as Novel Feeder Layers for Promoting Ex Vivo Expansion of Limbal Epithelial Progenitor Cells.

Ying-Ting Chen; Wei Li; Hayashida, Yasutaka; Hua He; Szu-Yu Chen; Tseng, David Y.; Kheirkhah, Ahmad; Tseng, Scheffer C. G.

Human amniotic epithelial cells (HAECs) are a unique embryonic cell source that potentially can be used as feeder layers for expanding different types of stem cells. In vivo, HAECs uniformly expressed pan-cytokeratins (pan-CK) and heterogeneously expressed vimentin (Vim). The two phenotypes expressing either pan-CK( )/Vim( ) or pan-CK( )/Vim(-) were maintained in serum-free media with high calcium. In contrast, all HAECs became pan-CK( )/Vim( ) in serum-containing media, which also promoted HAEC proliferation for at least eight passages, especially supplemented with epidermal growth factor and insulin. Mitomycin C-arrested HAEC feeder layers were more effective in promoting clonal growth of human limbal epithelial progenitors than conventional 3T3 murine feeder layers. Cells in HAEC-supported clones were uniformly smaller, sustained more proliferation, and expressed less CK12 and connexin 43 but higher levels of stem cell-associated markers such as p63, Musashi-1, and ATP-binding cassette subfamily G2 than those of 3T3-supported clones. Subculturing of clonally expanded limbal progenitors from HAEC feeder layers, but not from 3T3 feeder layers, gave rise to uniformly p63-positive epithelial progenitor cells as well as nestin-positive neuronal-like progenitors. Collectively, these results indicated that HAECs can be used as a human feeder layer equivalent for more effective ex vivo expansion of adult epithelial stem cells from the human limbus.

EPITHELIAL cells; EMBRYONIC stem cells; EPIDERMAL growth factor; MITOMYCIN C; IMMUNOSUPPRESSIVE agents; PANCREATIC secretions

Stem Cells, 2007, Vol 25, Issue 8, p1995

1066-5099

Academic Journal

10.1634/stemcells.2006-0677