Studies On The Function Of Vascular Endothelial Cell And Its Regulation

Vascular endothelial cells between the blood and the surrounding vascular tissue play a central role in hemastatic balance,angiogenesis,ionizing radiation,and inflammation. Recent advances in cell biology,biochemistry and molecular biology have seen the new physiological functions of endothelial cells. The studies aim at the function of vascular endothelial cells and its regulation.1 -. Studies on the inhibition of angiogenic properties by monoclonal antibody against integrinEndothelial cell adhesion and migration are important processes during angiogenesis. The capacity of endothelial cells to recognize and migrate in response to the extracellular matrix (ECM) depends on one or more members of the integrin family of cell adhesion receptors. Among them is a v B 3,the endothelial cell receptor for fibronectin,vitronectin and a wide variety of ECM components.SZ-21,a murine monoclonal antibody aganist platelet glycoprotein (GP)IIIa (ie,integrin PS),inhibited human platelet aggregation through the blokade of fibrinogen binding to its receptor. In our study,SZ-21 exhibited inhibitory effects on human umbilical vein endothelial cell line (ECV304) and human lung carcinoma cells (A549)adhesion and migration to extracellular matrix proteins ( ie,fibronectin and Collagen IV). In addition,it disrupted ongoing angiogenesis on the chick chorioallantoic membrane (CAM) model. SZ-21 also induced apoptosis of the A549 cells,hi conclusion,SZ-21 inhibits angiogenesis in vivo and in vitro by blocking integrin P 3 and inducing apoptosis. The interaction of integrins with extracellular matrix has been shown to be mediated through an arginine-glyclne-aspartic acid (ROD) sequence within adhesive proteins. It was reported that SZ-21 recognized the sequence ?3 28-35 which is far away from the ROD ligation site on GPIIIa. The results may indicate that integrin interacts with the extracellular matrix via SZ-21 recognition sites other than ROD sequence.