The regulatory effect of semaphorin 7A on proliferation and migration in human umbilical vein endothelial cells
Mentor:Donna Nofziger-Plank, Associate Professor of Biology, Pepperdine University
Semaphorin 7A (SEMA 7A), a factor originally identified as regulating axon growth, has recently been implicated as a pro-angiogenic factor. The molecular mechanisms for this ability to stimulate angiogenesis have not been well characterized. This study examines if SEMA 7A can have a direct effect on vascular endothelial cells or whether it indirectly induces angiogenesis through stimulation of macrophages. Using human umbilical vein endothelial cells (HUVECs) that have been exposed to growth media without the pro-angiogenic factor vascular endothelial growth factor A (VEGFA) and growth media with VEGFA, the ability of SEMA 7A to affect proliferation and migration of endothelial cells was examined. Both proliferation assays and migration assays were performed on HUVECs exposed to SEMA 7A directly or to conditioned media collected from macrophages exposed to SEMA 7A. Direct exposure of HUVECs to SEMA 7A resulted in a significant decrease in cell proliferation while no difference in HUVEC proliferation was detected using media collected from macrophages exposed to SEMA 7A. Results from a transwell migration assay suggest that direct exposure of SEMA 7A results in an inhibitory effect on the ability of HUVECs to migrate. Together, these results suggest that SEMA 7A may directly inhibit the ability of HUVECs to proliferate and migrate in response to VEGFA.