PECAM1 and Legg-Calve-Perthes disease: An article details that LCPD patients usually have a high level of interleukin-6 in their plasma, and the high concentration of interleukin-6 can prompt human umbilical vein endothelial cells to secrete CD31+/CD42b− endothelial microparticles, which lead to endothelial cell apoptosis and dysfunction, as well as inhibit angiogenesis (18).