DIFFERENTIATION AND BIOLOGICAL CHARACTERISTICS OF THE LYMPHATIC ENDOTHELIAL PROGENITOR CELLS ISOLATED FROM UMBILICAL CORD BLOOD / 解剖学报

ABSTRACT

Objective To study the changes of biological characteristics of CD34~+/CD133~+/VEGFR-3~+ lymphatic endothelial progenitor cells(EPCs) isolated from umbilical cord blood after induction with VEGF-C and investigate the mechanisms of EPCs differentiation toward lymphatic endothelial cells. Methods Mononuclear cells were isolated from umbilical cord blood using density centrifugation with Percoll solution.CD34~+/CD133~+/VEGFR-3~+ cells were sorted with FACS.Differentiation of the cells was induced with VEGF-C.The ultrastructural changes of the cells were viewed under scanning and transmission electron microscopes.Changes in expression of markers of the cells were viewed under confocal laser scanning microscope. Results Lymphatic EPCs isolated from umbilical cord blood expressed CD34,CD133 and VEGFR-3.At 7 day after induction with VEGF-C,CD34~+/CD133~+/VEGFR-3~+ cells were shuttle-like,there were a lamellipodium,numerous filopodia and many short microvilli.Caveolae were observed.Mitochondrion and rough endoplasmic reticulum were rich in cytoplasm.At 14 day after induction,the cells demonstrated appearance of the endothelial cell and expressed lymphatic endothelial specific makers LYVE-1 and 5'-nucleotidase,the expression of CD133 disappeared.Weibel-Palade body was observed in the cytoplasm of the cell.Conclusion There are CD34~+/CD133~+/VEGFR-3~+ lymphatic EPCs in human umbilical cord blood.The cells may differentiate into lymphatic endothelial cells through VEGF-C/VEGFR-3 signaling pathway after induction with VEGF-C.