Characterization of mesenchymal stem cells (MSCs) from human fetal lung: potential differentiation of germ cells.

Pluripotent mesenchymal stem-like cell lines were established from lungs of 3-4 months old aborted fetus. The cells present the high ex vivo expansion potential of MSC, a typical fibroblast-like morphology and proliferate up to 15 passages without displaying clear changes in morphology. Immunological localization and flow cytometry analyses showed that these cells are positive for OCT4, c-Kit, CD11, CD29, CD44, telomerase, CD106, CD105, CD166, and SSEA1, weakly expression or negative for SSEA1, SSEA3, SSEA4, CD34, CD105 and CD106. These cells can give rise to the adipogenic as evidenced by accumulation of lipid-rich vacuoles within cells identified by Oil-red O when they were induced with 0.5 mM isobutylmethylxanthine, 200 microM indomethacin, 10(-6)M dexamethasone, and 10 microg/ml of insulin in high-glucose DMEM. Osteogenic lineage cells were generated in 0.1 microM dexamethasone, 50 microg/ml ascorbic acid, 10 mM beta-glycerophosphate, which are shaped as the osteoblastic morphology, expression of alkaline phosphatase (AP), and the formation of a mineralized extracellular matrix identified by Alizarin Red staining. Neural cells are observed when the cultures were induced with 2-mercapometal, which are positive for nestin, NF-100, MBP and GFAP. Additionally, embryoid bodies (EBs) and sperm like cells are obtained in vitro differentiation of these lung MSCs induced with 10(-5)M retinoic acid (RA). These results demonstrated that these MSCs are pluripotent and may provide an in vitro model to study germ-cell formation and also as a potential source of sperms for male infertility.