Immune studies with T-2 toxin: effect of feeding and withdrawal in monkeys.

Ingestion of T-2 toxin, a product of Fusarium fungi, has been reported to have a variety of effects leading to morbidity and mortality in animals and humans. Semi-purified T-2 toxin was given to monkeys by gastric intubation at a level of 100 microgram/kg body weight/day for 4-5 wk and the haematological and immune parameters were studied before and after the treatment. Leucocyte counts were depressed at the end of wk 4 of treatment. The immunological studies studies showed suppression of the bactericidal activity of neutrophils, of cell-mediated immune status as assessed by T-cell number and lymphocyte transformation, and of humoral immunity as reflected in B-cell number and IgG and IgM levels. However serum complement (CH50) did not show any change. Investigations carried out 5 months after withdrawal of the toxin indicated that these parameters had returned almost to the initial, pretreatment levels. These data suggest that the greater incidence of infection seen in mycotoxin-ingesting animals may be due to immune suppression. Withdrawal of the mycotoxin results in improvement of haematological and immune functions.