Detection of altered secondary lymphoid-tissue chemkine responsiveness in Balb/c mice infected with Schistosoma mansoni.

To determine the extent to which Balb/c mice splenic T cells were affected by S. mansoni infection, this study aims to investigate the ability of the T cells to produce interferon (IFN)-&, and their chemotactic ability at 7 weeks post-infection. The splenic T cells were capable of producing levels of IFN-& comparable with splenic T cells from naive mice. However, the T cells exhibited altered chemotactic activity, as evidenced by an inability to respond to secondary lymphoid-tissue chemokine (SLC/CCL21). Although no difference in chemokine expression was found between the spleens of infected versus control mice, chemokine production was greater in the livers of infected versus control mice. Collectively, these data indicate that Balb/c mice with 7-wk S. mansoni infection possess splenic T cells with altered chemotactic activity and that the alterations may be a consequence of granulomatous response in the liver.

Some molecular aspects in schistosomiasis mansoni and toxoplasmosis.

The IL-2 and IL-4 cytokines production represent cellular Th1 & Th2 immune responses respectively were associated with chronic schistosomiasis mansoni (stages 1-4) and chronic toxoplasmosis gondii. In the hepatosplenic schistosomiasis, the level of IL-2 and disease stage increased in parallel (P<0.05, <0.01, <0.01 & <0.001 in stages 1, 2, 3 & 4 respectively), whereas, IL-4 was highly significantly increased in stage 1 than control (P<0.001), then decreased to lower levels. The mean concentrations of IL-2 & IL-4 in patients with T. gondii were higher compared to control being more marked in IL-2 (P<0.001) versus IL-4 (P< 0.01). The data indicated that there are patterns of cytokine expression characteristic of type 1 & type 2 responses in vivo, with the ultimate goal of being able to manipulate the response to minimize inflammation and fibrosis for clinical benefit.