Effect of cytokines secreted by human adipose stromal cells on endothelial cells

To isolate and culture adipose stromal cells (ASCs), and study the effect of cytokines secreted by ASCs on endothelial cells, human adipose tissue was digested with collagenase type I solution and ASCs were derived by culture. The cells surface phenotype was examined by flow cytometry. ELISA was used to detect the secretion of VEGF, HGF, SDF-1 alpha and RT-PCR was employed to detect the expression of their mRNA. Then the ASC medium was utilized to culture human umbilical vein endothelial cells ECV304. Cells were counted by hemacytometer to determine the proliferation and Annexin V/ PI was employed for the examination of the apoptosis rate of ECV304. ASCs were derived by culture and expressed CD34, CD105 while they did not express CD31 or CD45. ASCs secreted cytokines such as VEGF, HGF and SDF-1 alpha so the ASC medium could stimulate proliferation and counteract apoptosis of endothelial cells (P < 0.05). Bcl-2 mRNA was also found to be up-regulated in the endothelial cells. It is concluded that ASCs can secrete cytokines and has significant effect on the proliferation of endothelial cells and apoptosis.