ABSTRACT
Two isolation methods for sorting of endothelial progenitor cells(EPCs): from peripheral blood mononuclear cells(PBMCs)and CD133+ enriched cells were compared,by defining the cell morphology,phenotype,reproductive activities and function in vitro,to provide a reference for clinical application of EPCs.PBMCs from healthy subjects were used either directly for cell culture or for CD133+ sorting.The two groups of cells were cultured in complete medium 199(M199)for 7 to 14 days and the phenotypes of EPCs were analyzed by FACS.The proliferation of differentiated EPCs was studied by MTT assay,and the VEGF concentration was measured using an ELISA kit.ECM gel experiment and migration assay were performed in vivo.The results showed that PBMCs produced more colony-forming units(CFU)than CD133+enriched cells from the same volume of blood(P<0.01).From day 7 to 14,the two groups showed decreased expression of hematopoietic stem cell markers and increased level of endothelial markers,but CD144+cells in CD133+ group were less than in PBMCs group(P<0.01).PBMCs group secreted more VEGF than CD133+group on the day 7(P<0.01).As compared with CD133+ group,PBMCs group had more potent potential of proliferation and vascularization in vitro.It was concluded that CD133+sorted cells showed a lower capacity of differentiation,secretion,proliferation and vascularization in vitro,suggesting that CD133-negative cells may be a preferential way to get EPCs for clinical therapy.
ABSTRACT
In order to investigate the effect of replication-incompetent adenovirus vector expressing MDA-7/IL-24 on tumor growth and apoptosis of human hepatocellular carcinoma (HCC) cell line SMMC-7721 and normal liver cell line L02, the recombinant replication-incompetent Ad.mda-7 virus vector was constructed and infected into the HCC cell line SMMC-7721 and normal liver cell line L02. RT-PCR was performed to examine the expression of MDA-7 mRNA. The concentrations of MDA-7/IL-4 in culture supernatants were determined by using ELISA. MTT and Hoechst staining assay were applied to observe the inhibitory and killing effects of MDA-7 on the HCC cells. By using flow cytometry, the apoptosis, cell cycle and proliferation of SMMC-7721 and L02 cells were meas- ured. The results showed recombinant replication-incompetent virus expressing MDA-7/IL-24 was constructed successfully, and RT-PCR revealed that it could mediate the high expression of the ex- ogenous gene MDA-7/IL-24 in SMMC-7721 and L02 cells. The expression of MDA-7/IL24 proteins in the culture supernatant was detectable by ELISA. Ad.mda-7 infection induced apoptosis and growth suppression in SMMC-7721 cells and an increased percentage of HCC cells in the G2/M phase of the cell cycle, but not in L02 cells. It was concluded that mda-7/IL-24 gene, mediated with replication-incompetent adenovirus vector, could selectively induce growth suppression and apoptosis in HCC cell line SMMC-7721 but without any toxic side-effect on normal liver line L02.