Vascular Endothelial Growth Factor-A Is Stored in and Immunologically Released from Human Basophils

摘要

Angiogenesis is a multistep complex phenomenon critical for several inflammatory and neoplastic disorders. Basophils, normally confined to peripheral blood, can infiltrate the sites of chronic inflammation. We have characterized the expression and localization of vascular endothelial growth factor-A (VEGF-A) in these cells. Basophils express mRNA for three isoforms of VRGF-A (121, 165, and 189). Peripheral blood basophils contain VEGF-A localized in secretory granules, lmmunologic activation of basophils induced the release of VEGF-A. Our data suggest that basophils play a role in angiogenesis and inflammation through the expression and release of several isoforms of VEGF-A. Angiogenesis is a complex multistep process that culminates in the growth of new blood vessels from the microcirculation [1]. It is critical for such chronic inflammatory disorders as bronchial asthma [2, 3], rheumatoid arthritis [4] and tumor growth [1]. Vascular endothelial growth factor (VEGF) is the most potent pro-angiogenic mediator known so far. Originally identified from its ability to induce vascular permeability [5], VEGF is a potent inducer of endothelial proliferation, migration, and survival. It also acts as a proinflammatory cyto-kine [1].