Immune Properties Of Humscs And Humscs Differentiated Into Germ-like Cells

Objective: To investigate the immune properties of Human umbilical cord Wharton's Jelly-derived mesenchymal stem cells (huMSCs) and huMSCs differentiated into germ-like cells in vitro,in order to provide experimental data for future fundamental study on transplantation.Methods: Isolated and cultured huMSCs, and induced huMSCs differentiated into germ-like cells in an artificial microenvironment in vitro. The morphology of huMSCs after induction were monitored by under inversion phase contrast microscope. The expressions of CD40,CD40L,CD80,CD86 molecules on the surface of huMSCs and huMSCs differentiated into germ-like cells were detected by flow cytometry. The expression of HLA-I and HLA-DR were examined in both differentiated and undifferentiated huMSCs cells using RT-PCR. Inhibition of the proliferation of allogenic PBMC stimulated by PHA were detected with addition of different number of differentiated and undifferentiated huMSCs cells by mixed lymphocyte culture (CCK-8 method), and detected the secretion of IFN-γby PHA-activated T lymphocytes using enzyme linked immunosorbent assay(ELISA).Results: The morphology of huMSCs under artificial microenvironment induction gradually changed from fibroblast to slender spindles and formed a"tadpole-like"shape. Both differentiated and undifferentiated huMSCs cells express HLA-I but not express CD40,CD40L,CD80,CD86,HLA-DR. Mixed lymphocyte assays showed only undifferentiated huMSCs cells can suppress the proliferation of allogenic PBMCs. ELISA detected the supernatants from differentiated and undifferentiated huMSCs cells cocoltured with PHA-activated T lymphocytes also showed that only undifferentiated huMSCs cells can decrease the secretion of IFN-γby T lymphocytes.Conclusion: huMSCs can be differentiated into germ-like cells in vitro, the"germ-like cells"and huMSCs possess weak immunogenicity, huMSCs also perform immunoregulatory functions by suppressing T lymphocyte proliferation in vitro, but the"germ-like cells"seem don't have the immunosupresssion character in vitro.