The experimental study on differentiation of human umbilical cord blood mesenchymal stem cells into neural cells induced by lithium chloride

Abstract

Objective To study the possibility of inducing human umbilical cord blood mesenchymal stem cells(MSCs) to differentiate into neuron-like cells by lithium chloride(LiCl) in vitro.Methods Human umbilical cord blood was collected from mature neonates.All samples were obtained sterilely with 20 U/ml heparin.The cord mononuclear cells were isolated with lymphocyte separation medium(density 1.077 g/ml), then purified by wall sticking screening and expanded with slight sugar DIEM containing 15% FBS.The third passage of the expanded MSCs were pre-inducted with DIEM containing 15% FBS and 20 ng/ml bFGF for 24 hours, then induced with DIEM without serum but 3 mol/L LiCl for 6 days in group A.The MSCs were induced with DIEM containing 3 mol/L Licl for 7 days in group B.The MSCs were normally cultured with DIEM containing 15% FBS in group C.The morphological changes of the cells were observed under phase contrast microscope.The neuron specific markers containing neuron specific enolase(NSE), microtubule associated protein2(MAP2) and glial fibrillary acid protein(GFAP) were evaluated by indirect immunocyto-chemistry staining.Results After inducted for 3 days, morphological changes were observed obviously in group A and B.6 days later, the differentiated cells showed typical neuronal morphology.The expression of NSE and MAP2 were positive for the majority cells in group A and B, and that of group A[(73.6 ± 7.8)%, 75.5 ± 8.5)% respectively]were obviously higher than group B[(31.0 ± 4.3)%,(33.5 ± 5.0)% respectively], few expressed GFAP in both groups.Conclusion The combination of LiCl and growth factor may induce the human umbilical cord blood MSCs into neuron-like cells in vitro. Key words: Human umbilical cord blood; Mesenchymal stem cells; Lithium chloride; Neuion; Differentiation