EFFECTS OF AFLATOXIN B-1 AND T-2 TOXIN ON THE GRANULOCYTE-MACROPHAGE PROGENITOR CELLS IN MOUSE BONE-MARROW CULTURES

Myelotoxic effects of aflatoxin B-1 (AFB(1)) and T-2 toxin on the prol iferation of the granulocyte-macrophage progenitor cells to granulocyt e, macrophage and granulocyte-macrophage (GM) colonies were investigat ed in male CD-1 mice by a semisolid in vitro culture technique. Mice r eceived 0, 0.03, 0.145 and 0.7 mg/kg or 0, 0.1, 0.5, and 2.5 mg/kg bod y weight of AFB(1) and T-2 toxin, respectively, for 2 weeks on alterna te days. Granulocyte, macrophage, and GM-colonies were suppressed in t he group that received the highest dose of AFB, (0.7 mg/kg body weight ). Treatment with T-2 toxin activated granulocyte colonies at 0.5 mg/k g and macrophage colonies at 0.1 and 2.5 mg/kg but suppressed GM-colon ies at 0.5 and 2.5 mg/kg body weight. Bone marrow cells from normal CD -1 mice were cultured with different concentrations of AFB(1) (1-50 mu M) or T-2 toxin (1-10 nM) in vitro. Significant activation of granulo cyte colonies with 1 mu M AFB(1) and suppression of all three types of colonies with the highest concentration of AFB(1) (50 mu M) were obse rved. The suppression of granulocyte and GM-colonies associated with T -2 toxin was concentration-dependent. The greatest suppression occurre d in macrophage colonies with three highest concentrations of T-2 toxi n (3, 6, and 10 nM). Results suggest that AFB(1) is myelotoxic both in vivo and in vitro, whereas T-2 toxin is more toxic in vitro.