Fumonisin and beauvericin induce apoptosis in turkey peripheral blood lymphocytes

Fumonisins, a family of mycotoxins produced by Fusarium verticillioides (synonym Fusarium moniliforme Sheldon) and F. proliferatum, have been associated with various deleterious effects in different animal species. Serological, hematological and pathological effects and mortality have previously been observed in broiler chicks fed F. proliferatum culture material containing known concentrations of fumonisin, moniliformin and beauvericin. Turkey peripheral blood lymphocytes were exposed in vitro for 72 hours to fumonisin B-1 (FB1), fumonisin B-2 (FB2), hydrolyzed fumonisin B-1 (HFB1), moniliformin and tricarballylic acid (TCA) (0.01- 25 mug/ml). A decrease in cell proliferation, as determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] bioassay, occurred in the order: FB2 > FB1 > HFB1, with IC50 = 0.6 muM, 1 muM and 10 muM, respectively. Internucleosomal DNA fragmentation and morphological features characteristic of apoptosis were observed following exposure to fumonisin B-1 and beauvericin; cytoplasmic condensation and membrane blebbing were seen by light microscopy. Tricarballylic acid and moniliformin did not interfere with cell proliferation. Results suggested that fumonisin B-1 and beauvericin may affect immune functions by suppressing proliferation and inducing apoptosis of lymphocytes.