Recombinant Human Placental Growth Factor-1 (PIGF-1, also referred to as PLGF-1) is a bioactive protein intended for use in cell culture and related applications. PIGF-1 is active in angiogenesis, as well as in the stimulation, proliferation, and migration of endothelial cells. PlGF-1 is expressed in placental tissues, the colon, and mammary carcinomas. It signals through the VEGFR-1/FLT1 receptor, and stimulates endothelial cell proliferation and migration.