Basic Fibroblast Growth Factor Increases Expression of the αvβ3 Integrin Complex on Human Microvascular Endothelial Cells

Abstract Modulation of the expression of the α v β 3 complex on human dermal microvascular endothelial cells (HDMEC) may be crucial in wound healing and angiogenesis. Therefore, we examined the influence of basic fibroblast growth factor (bFGF), transforming growth factor β, and interferon-γ (IFN-γ) on the expression of this complex. Stimulation of HDMEC with bFGF increased cell surface expression of both α v and β 3 in a dose- and time-dependent manner associated with the development of a spindled, elongated cell morphology. Northern blot analysis of HDMEC stimulated with bFGF demonstrated a marked increase in β 3 but not α v mRNA expression. Incubation of HDMEC with transforming growth factor-α or interferon-γ alone resulted in modest decreases in cell surface α v β 3 , and co-incubation of HDMEC with bFGF and transforming growth factor-β or interferon-γ inhibited bFGF-induced changes in cell morphology, increases in cell surface α v β 3 expression, and increases in β 3 mRNA. These data demonstrate that both growth factors and pro-inflammatory cytokines alter the expression of α v β 3 on microvascular endothelial cells and that these alterations correlate with changes in cell morphology.