Study on adherent precursors from human cord blood

AIM: To confirm the existence of the endothelial progenitor cells in human cord blood and to study its differentiation and development process. METHODS: The mononuclear cells in human cord blood were isolated using lymphocyte separation solution. Then the mononuclear cells were cltured in MCDB131 containing 20% fetal bovine serum. The effects of 5 μmol/L dexamethasone, the extract from bovine brain, insulin and hypoxanine on the proliferation and differentiation of the adherent cells were observed. The morphology of the adherent cells were examined twice daily by inverted phase contrast microscope. CD34 and CD14 expression were determined by FACS. Immunohistochemistry was used to confirm the expression of factor Ⅷ. RESULTS: The proliferative endothelial progenitor cells existed within the CD34^-adherent mononuclear cells of human cord blood. Dexamethasone and hypoxanine decreased the number of spindle-shaped cells and caudated cells. Bovine brain extract, insulin and FCS enhanced the number of spindle-shaped cells and caudated cells. CONCLUSION: The existence of endothelial progenitor cells within the CD34 - adherent monouclear cells of the human cord blood was observed and these cells were able to differentiate into endothelial-like cells in vitro.