BASIC FIBROBLAST GROWTH-FACTOR INCREASES EXPRESSION OF THE ALPHA(V)BETA(3) INTEGRIN COMPLEX ON HUMAN MICROVASCULAR ENDOTHELIAL-CELLS

Modulation of the expression of the alpha(v) beta(3) complex on human dermal microvascular endothelial cells (HDMEC) may be crucial in wound healing and angiogenesis. Therefore, we examined the influence of bas ic fibroblast growth factor (bFGF), transforming growth factor beta, a nd interferon-gamma (IFN-gamma) on the expression of this complex. Sti mulation of HDMEC with bFGF increased cell surface expression of both alpha(v) and beta(3) in a dose- and time-dependent manner associated w ith the development of a spindled, elongated cell morphology. Northern blot analysis of HDMEC stimulated with bFGF demonstrated a marked inc rease in beta(3) but not alpha(v) mRNA expression. Incubation of HDMEC with transforming growth factor-beta or interferon-gamma alone result ed in modest decreases in cell surface alpha(v) beta(3), and co-incuba tion of HDMEC with bFGF and transforming growth factor-beta or interfe ron-gamma inhibited bFGF-induced changes in cell morphology, increases in cell surface alpha(v) beta(3) expression, and increases in beta(3) mRNA. These data demonstrate that both growth factors and pro-inflamm atory cytokines alter the expression of alpha(v) beta(3) on microvascu lar endothelial cells and that these alterations correlate with change s in cell morphology.