Inhibition of mitogen-induced blastogenesis in human lymphocytes by T-2 toxin and its metabolites.

Concentrations of T-2, HT-2, 3'-OH T-2, 3'-OH HT-2, T-2 triol, and T-2 tetraol toxins which inhibited [3H]thymidine uptake in mitogen-stimulated human peripheral lymphocytes by 50% were 1.5, 3.5, 4.0, 50, 150, and 150 ng/ml, respectively. The results suggested that the initial hydrolysis of T-2 toxin and the hydroxylation of T-2 toxin to 3'-OH T-2 toxin did not significantly decrease the immunotoxicity of the parent molecule, whereas further hydrolysis to T-2 triol and T-2 tetraol toxins or hydroxylation to 3'-OH HT-2 toxin decreased in vitro toxicity for human lymphocytes.