Augmentation of recombinant fibronectin polypeptide CH50 on the antitumor function of macrophages.

We prepared an anti-metastatic polypeptide, recombinant fibronectin polypeptide CH50, and finished the preliminary identification of its functions. In this paper, we studied the effect of this polypeptide on the function of macrophages. CH50 can significantly augment the production of nitric oxide(NO) by macrophages in a dose-dependent manner. The continuous presence of CH50 had a much stronger effect. In the presence of CH50, the cytotoxicity of macrophages to melanoma B16/F1 cells was significantly enhanced, and a stronger effect was obtained if CH50 was present continuously. CH50 polypeptide and IFN-gamma have a synergistic effect on the production of NO by macrophages and the cytotoxicity of macrophages on tumor cells. In the in vivo experiments, CH50 can inhibit the growth of tumor cells, and have a better effect in the presence of IFN-gamma. Our results suggest that recombinant fibronectin polypeptide CH50 has two functions: one is to inhibit the metastasis of tumor cells, and the other one is to augment the function of macrophages. And this polypeptide will be potentially useful in tumor therapy.