Inhibition of establishment and growth of mouse liver metastases after treatment with interferon gamma and β-1,3-D-glucan

Abstract

The purpose of this study was to investigate the combined antitumor effect of aminated β-1,3-D-glucan (ag) and interferon-gamma (IFN-γ) in an experimental liver metastasis model. Liver metastases were established by inoculation of C-26 colon carcinoma cells into the superior mesenteric vein of syngeneic mice. Treatment of mice started 24 hours after inoculation of tumor cells by daily intravenous injections of either Ag, Ifn-γ, or a combination of both for a duration of 6 days. The resultant liver metastases were then quantified after an additional period of 11 days. Combination of Ifn-γ and Ag inhibited the growth of liver metastases almost entirely. Ifn- γ was also very efficient, while Ag alone did not exert any significant antitumor effect. These results, along with histological studies from mice receiving Ag and Ifn-γ, indicated that activation and recruitment of liver macrophages may be a part of the mechanism responsible for the inhibition of metastatic growth observed in this study.