Effect of fumonisin-B1 exposure on chicken macrophage functions in vitro

Fumonisin-B1 (FB1) is one of the recently discovered metabolites of Fusarium moniliforme (Sheldon) occurring naturally in infected corn. It is hepatocarcinogenic and causes death in several animal species including rats, horses, swine, and ducklings. In the present study, chicken peritoneal macrophages (PM) and a chicken macrophage cell line, MQ-NCSU, were exposed in vitro to various doses of FB1. Exposure to .5, 5, and 10 micrograms FB1/mL caused significant cytotoxicity in PM after 2 and 4 h of exposure. Morphological alterations induced by FB1 in PM included cytoplasmic blebing or nuclear disintegration or both, which were maximal in cultures treated with 20 micrograms FB1/mL. Significant depression in the phagocytic potential of PM occurred after 4 h treatment with 20, 40, and 100 micrograms FB1. However, exposure to FB1 alone, as well as after stimulation with lipopolysaccharide, induced secretion of a cytolytic factor by MQ-NCSU cells. These findings, which showed that FB1 exposure induced morphological and functional alterations in chicken macrophages, imply that FB1 exposure may result in increased susceptibility of chickens to bacterial infection.