Cytotoxicity and genotoxicity of gliotoxin on human lymphocytes in vitro

The cytotoxic effects on human lymphocytes of two gliotoxin samples (one pure sample produced in the laboratory for this study, and one sample purchased from a standard source) were assessed at four different concentrations (25, 50, 100 and 200 ng/ml) using the methylthiazol tetrazolium (MTT) bioassay. The results showed that growth was inhibited by 21, 39.10, 61.99 and 87.45% for each of the four concentrations of the pure sample, respectively, and by 17.89, 34.92, 58.34 and 85.22% respectively, in the case of the standard purchased sample. Deoxyribonucleic acid (DNA) was extracted from the lymphocytes and analysed by electrophoresis on a 1% agarose gel. Gliotoxin appeared to have the ability to degrade or damage the DNA. The present study showed that both the growth inhibition and DNA damage experienced by the human lymphocytes increased linearly with increasing concentrations of toxin.