CHOLERA-TOXIN AND SALMONELLA-TYPHIMURIUM INDUCE DIFFERENT CYTOKINE PROFILES IN THE GASTROINTESTINAL-TRACT

Salmonella infection of the gastrointestinal tract (GT) results in fluid secretion and inflammation. In contrast, cholera toxin (CT) induces fluid secretion but no inflammation. Using a murine ligated intestinal loop model, we investigated cytokine production (interleukin-1 [IL-1], IL-2, IL-4, IL-6, IG-10, gamma interferon, and tumor necrosis factor alpha) in the GT following exposure to these agents. Salmonella typhimurium induced a Th-1-like cytokine profile in loops obtained from either nonimmune mice or Salmonella-immunized mice. CT induced only IL-6 and IL-10 production in ligated loops from nonimmune mice but induced a Th-2-like cytokine profile in ligated loops obtained from CT-immunized mice. These results show that CT and S. typhimurium induce very different cytokine profiles in the GT.