Leukocyte migration through endothelium is induced by ?

Ans. is 'd' i.e., PECAMMigration of the leukocytes through the endothelium is called transmigration or diapedesis.Transmigration of leukocytes occurs mainly in postcapillaryvenules.The molecules involved in transmigration are member of the immunoglobulin superfamily called CD31 or PECAM-1 (platelet endothelial cell adhesion molecule).