Objective: To observe the dynamic changes of the proportions of T cytotoxic type 1 (Tc1) cells and T cytotoxic type 2 (Tc2) cells and analyze the correlation of them with the dynamic changes of the proportions of Th1 and Th2 cells in T lymphocytes respectively at different stages after Schistosoma japonicum infection.
Method: Splenocytes were prepared from spleens of mice with S. japonicum infection at different stages (0, 3, 5, 8, 13 weeks), and the proportions of Tc1, Tc2 and Th1, Th2 cells in T cells were determined by FACS, respectively.
Results: Compared to the control group (0 week), the proportions of Tc1 cells significantly increased 3, 5, 8, 13 weeks post-infection (all P values < 0.01) and the proportions of Tc2 cells at different stages (5, 8, 13 weeks) post-infection also increased significantly (all P values < 0.01). During the first 3 weeks post-infection, the proportions of Tc1 cells increased most quickly than Tc2 cells did and Tc1 cells did at the other stages post-infection. However, the proportion of Tc2 cells increased most quickly 5 weeks post-infection than both Tc1 cells did and Tc2 cells did at the other stages post-infection. A positive correlation was found between the increases of the proportions of Thl cells and Tc1 cells ( r = 0.978, P = 0.004), and a positive correlation was also found between the increases of the proportions of Th2 cells and Tc2 cells ( r = 0.974, P = 0.005). The SWA stimulation of splenocytes of mice in vitro significantly increased the proportion of Tc1 cells (P < 0.01) while the SEA stimulation of splenocytes of mice in vitro significantly increased the proportion of Tc2 cells ( P < 0.01).
Conclusions: The proportions of Tc1 cells and Tc2 cells in T cells are significantly increased at different stages after S. japonicum infection. Tc1 cells are increased most quickly 3 weeks post-infection, and Tc2 cells are increased most quickly 5 weeks post-infection. A positive correlation is found between the proportions of Th cells and Tc cells in CD3+ T cells. SWA preferentially induces the increase of Tc1 cells in CD3+ T cells while SEA preferentially induces the increase of Tc2 cells in CD3+ T cells in vitro.