Overexpression of laminin-8 in human dermal microvascular endothelial cells promotes angiogenesis-related functions.

This study examined the effects of endogenous overexpression of laminin-8 on angiogenesis and wound healing in primary human dermal microvascular endothelial cells (HDMECs). HDMECs expressed laminin-8 and laminin-10, but no other laminins, as determined by radioimmunoprecipitation assay using a panel of antibodies to individual laminin chains. To study laminin-8 function, full-length human laminin alpha4 cDNA was retrovirally transferred to HDMEC, and specific overexpression of laminin-8 was verified by Western blot. Laminin-8 overexpression promoted endothelial cell spreading and migration in scratch assays and accelerated angiogenic tubule formation in collagen gel overlay assays. Strong inhibitory effect of beta1 integrin and weak inhibition by alphavbeta3 integrin antibodies were observed in laminin-8-stimulated cell migration, but only beta1 integrin antibodies affected tubule formation. These studies suggest that laminin-8 overexpression may prove to be a useful method to engineer HDMECs to promote angiogenesis and wound repair.