Immunofluorescent Staining on Differentiation of Mononuclear Cells from Rat Umbilical Cord Blood into Endothelial Progenitor Cells

Objective Umbilical cord blood(UCB)is best containing a lot of endothelial progenitor cells(EPCs),they are progenitors of vascular endothelial cells(VECs)and capable of differentiation into VECs.It will lead to a new strategy to promote angiogenesis in bone tissue engineering.The purpose of this study was to analyze the potentiality on differentiation of mononuclear cells from rat umbilical cord blood into endothelial progenitor cells in vitro.Methods To isolate mononuclear cells from umbilical cord blood, they were cultured in conditioned medium(supplemented with 10%FBS,1%penicilin,1%phytomycin,VEGF 20μg/L,IGF-1 2μg/L,bFGF 2μg/L,EGF 20μg/L).The immunofluorescent staining were used to observe expressions and distributions of some special surface marker,such as CD34、CD133、Flk-1 and vWF on adherent cells after 3 weeks and 6 weeks.Result The results of the immunofluorescent staining were positive on CD34、CD133、Flk-1 and vWF after 3 weeks,but their results were only positive on CD34、Flk-1 and vWF after 6 weeks,the part of adherent cells were positive on CD133,the positive cells were not found in the control group.Conclusion The mononuclear cells from rat umbilical cord blood were induced into endothelial progenitor cells after 3 weeks in vitro.the part of adherent cells differentiated into mature vascular endothelial cells.