RESUMO
The ability of nematodes to manipulate the immune system of their host towards a Th2 and T regulatory responses has been proposed to suppress the inflammatory response. Clinical trials have proposed a useful effect of helminth infections on improvement of inflammatory disorders. In this study, we investigated the immunomodulatory effect of Syphacia obvelata infection to induce intestinal tolerance in C57BL/6 mice. Mice were infected through the cagemates with self-infected BALB/c mice. Four weeks post-infection, expression levels of IFN-γ, TNF-α, IL-17, and IL-10 were assessed in the supernatant of mesenteric lymph node (MLN) culture. Foxp3⁺Treg were measured in MLN cells by flow cytometry. In the S. obvelata-infected group, the percentage of Tregs (5.2±0.4) was significantly higher than the control (3.6±0.5) (P<0.05). The levels of IL-10 (55.3±2.2 vs 35.2±3.2), IL-17 (52.9±3.8 vs 41±1.8), IFN-γ (44.8±4.8 vs 22.3±2.3) and TNF-α (71.1±5.8 vs 60.1±3.3) were significantly increased in infected mice compared to the control group (P<0.05). The above results showed the potential effects of S. obvelata to induce intestinal tolerance. Therefore, it seems that S. obvelata may increase the immunological suppressive function in the intestinal tract.