ADP에 의해서 활성화된 인혈관세포의 Prothrombin과 골타액단백 부착에 관여하는 Integrin αvβ3, αvβ5, α5β1의 특성

Background : One of the most important features of integrins is that they exist in active and inactive states. Adenosine diphosphate (ADP), which is usually secreted from activated platelets, may activate integrins on vascular cells. Each integrin has its own activation-dependent ligands that have much higher affinity to active form than inactive one. Integrins that might mediate adhesion of human vascular cells to prothrombin (PT) and bone sialoprotein (BSP) after ADP stimulation were investigated. Methods : PT and BSP were used as activation-dependent ligands in adhesion assay. Adhesions of human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (HASMC) were measured after stimulating with 100 μM of ADP, using ligand-coated 24-well plate and Fluorescence Multi-Well Plate Reader. Results : ADP activated HUVEC and HASMC to increase adhesions to PT and BSP in a dose-dependent manner. Adhesions of ADP-stimulated HUVEC to PT and BSP were almost completely inhibited by c7E3, a blocking monoclonal Ab to integrin β3 (96% and 92% inhibition, respectively), but not by P5H9, a blocking monoclonal Ab to integrin αvβ5. Adhesion of ADP-stimulated HASMC to PT was completely blocked by P5H9 (92% inhibition), but was not affected by c7E3. Adhesion of ADP-stimulated HASMC to BSP was partially inhibited either by P5H9 (46% inhibition) or by JBS5, a blocking monoclonal Ab to integrin α5β1 (75% inhibition), but was not affected by c7E3. However, it was completely blocked by cRGD (93% inhibition). Conclusion : These results indicate that the adhesion of ADP-stimulated HUVEC to PT or BSP was mediated by integrin αvβ3, and several integrins appeared to be involved in the adhesion of ADP-stimulated HASMC. While the adhesion of HASMC to PT was mediated by integrin αvβ5, the adhesion to BSP was associated with integrins αvβ5 and α5β1. KCI Citation Count: 0