Some characteristics of IL-5-producing T cells in mouse liver induced by Schistosoma japonicum infection.

Schistosome infection could cause significant liver damage in animal; Th2 cells play an important role in the progress of this disease. In our study, C57BL/6 mice were infected by Schistosoma japonicum and lymphocytes were isolated from the liver to detect some characteristics of interleukin-5 (IL-5)-producing T cells by different methods. The results revealed that S. japonicum infection could induce a large amount of IL-5 in mouse liver T cells by the means of fluorescent bead immunoassay and RT-PCR. Although, mouse liver contained many T cell subsets, such as Th cells, Tc cells, NKT cells, and γδ T cells. Fluorescence activated cell sorting results indicated that Th cells were the main source of IL-5 in the T cell population after phorbol 12-myristate 13-acetate and ionomycin stimulation. Moreover, the percentage of IL-5-producing Th cells continued to increase from 4 to 8 weeks after S. japonicum infection, which differed from the changes of IFN-γ(+) Th1 cells, IL-4(+) Th2 cells, and IL-17A(+) Th17 cells during S. japonicum infection. Additionally, cytokines co-expression results demonstrated that 36.2 % of IL-5(+) Th cells could express IL-4, and 10 % of it could produce IFN-γ or IL-17A. Collectively, these findings implied that IL-5-producing Th cells posses some properties which differ from other cytokines secreting Th cells.