Effects of endotoxin on the Th1/Th2 response in man

It was the purpose of this study to prove a shift of the T-helper cell response towards a Th2 immune response during endotoxemia. Eight healthy volunteers were injected with a bolus of endotoxin (4 ng/kg bodyweight). IL-2, IL-4, IL-10, IL-12 and IFN-gamma plasma cytokine concentrations were determined before and for five hours after endotoxin administration. The predominance of the Th2 immune response has been demonstrated via elevated IL-10 plasma levels, while the impairment of the Th1 response manifested itself with a decrease of IL-2 synthesis. IFN-gamma and IL-12 plasma cytokine levels were unchanged throughout the observation period. This study supports the hypothesis that a very early polarisation of the T-helper cell response towards Th2 cytokine synthesis may contribute to the depressed cell-mediated immune response under septic conditions.