Increased production of interferon-gamma, but not IL-4 mRNA, by streptozotocin in the popliteal lymph node assay

The popliteal lymph node (PLN) assay has been proposed as a tool to predict systemic autoimmune reactions induced by medicinal products and chemicals, the mechanisms of which are poorly understood. To determine whether PLN re sponses involved Th1 or Th2 cell control, or both, the effects of streptozo tocin (STZ), a prototypic immunotoxic compound, were analysed on the produc tion of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) mRNA by lymph node cells after injection into the hind footpad of C57 BL/6 mice. Strepto zotocin induced a dramatic increase in IFN-gamma mRNA production, which cor related with PLN responses as evidenced by augmented weight and cellularity indices. No effect on IL-4 mRNA synthesis was noted. These results suggest that a Th1 response is involved in the PLN response to STZ. Copyright (C) 2000 John Wiley & Sons, Ltd.