Distribution of fibroblast growth factors (FGFs) in tissues and structure-function studies with synthetic fragments of basic FGF.

Acidic and basic fibroblast growth factors (FGFs) are characterized by their high affinity for heparin and their capacity to stimulate angiogenesis in vivo. While both molecules are structurally distinct they have 53% homology in their primary sequence and exist in similar molecular forms. These heparin-binding growth factors are also characterized by a wide distribution, a characteristic that may be attributable, at least in part, to their production by endothelial cells and their storage in the extracellular matrix. Structure-function studies with synthetic fragments of basic FGF have identified two peptidic sequences that cross-react with FGF receptor and that can modulate the cellular response to basic FGF. Both functional domains bind radiolabeled heparin, inhibit cell growth, and can interfere with stimulation of neurite outgrowth, cell adhesion, and differentiated cell function. The possible application of these antagonists to defining the role of FGF in wound repair, nerve regeneration, and vascularization of the vasovasorum is discussed.