Enhancement of phagocytosis in mouse peritoneal macrophages by fragments of acidic fibroblast growth factor (aFGF).

Abstract To characterize the effects of acidic fibroblast growth factor (aFGF) in mouse peritoneal macrophages, the effects of aFGF fragments on phagocytosis were examined. Fragments that were tested included aFGF(1–15), aFGF(1–20), aFGF(1–29), Ala 16 -aFGF(1–29), aFGF(9–29) and aFGF(114–140). aFGF(1–29) induced an enhancement of phagocytosis in a dose-dependent manner and was more effective than any other fragments tested. Even in Ca 2 -and Mg 2 -free solutions, phagocytosis was enhanced by aFGF(1–29). However, the enhancement induced by aFGF(1–29) was completely inhibited in the presence of mannan (4 mg/ml). Furthermore, the enhancement of phagocytosis by aFGF(1–29) was suppressed by heparin (100 μ g/ml). The results of the present study suggest that the active region of aFGF that is responsible for the enhancement of phagocytosis corresponds to residues 15–29 and that phagocytosis, which is modulated by aFGF, is independent of extracellular Ca 2 and is mediated by mannose receptors.