Inhibition of various functions in murine peritoneal macrophages by aflatoxin B1 exposure in vivo

Aflatoxin B1 (AFB1) has been known to impair specific and nonspecific immun ity. In the present study, we tested various functions of murine peritoneal macrophages that were isolated and stimulated with LPS after AFB1 (400 mu g/5 ml/kg) was administered every other day for 2 weeks. AFB1 decreased pha gocytosis and the production of superoxide anion (O-2(-)) and hydrogen pero xide (H2O2), compared to those of corn oil-treated control group. In additi on, the production of NO and TNF-alpha was decreased in macrophages of AFB1 -treated mice. In vitro antitumor activity of in vivo AFB1-treated macropha ges was reduced against target cell, L929. Taken together, these results su ggested that AFB1 might have the immunosuppressive effect on macrophages af ter in vivo exposure, which was related to the antitumor activity reduction . (C) 1999 International Society for Immunopharmacology. Published by Elsev ier Science Ltd.