Roles of Th17 cells in pulmonary granulomas induced by Schistosoma japonicum in C57BL/6 mice.

In schistosomiasis, limited information is available about the role of interleukin-17 (IL-17) in lung, despite the fact that this cytokine plays a crucial role during pro-inflammatory immune responses. In our study, we observed CD4(+)T cells changed after the infection. Furthermore, ELISA and FACS results revealed that Schistosomajaponicum infection could induce a large amount of IL-17 in mouse pulmonary lymphocytes. IL-17-producing cells, including Th17 cells, CD8(+)T (Tc) cells, γδT cells and natural killer T cells, was also associated with the development of lung inflammatory diseases. FACS results indicated that Th17 cell was the main source of IL-17 in the infected pulmonary lymphocytes after phorbol-12-myristate-13-acetate (PMA) and Ionomycin stimulation. Moreover, FACS results revealed that the percentage of Th17 cells continued to increase as over the course of S. japonicum infection. Additionally, cytokines co-expression results demonstrated that Th17 cells could express more IL-4 and IL-5 than IFN-γ. Reducing IL-17 activity by using anti-IL-17 ameliorated the damage and decreased infiltration of inflammatory cells in infected C57BL/6 mouse lungs. Collectively, these results suggest Th17 cells is the major IL-17-producing cells population and IL-17 contributes to pulmonary granulomatous inflammatory during the S. japonicum infection.

Chen D ，Xie H ，Luo X ，Yu X ，Fu X ，Gu H ，Wu C ，Tang X ，Huang J ... -  《-》

Characteristics of IL-17 induction by Schistosoma japonicum infection in C57BL/6 mouse liver.

Schistosomiasis japonica is a severe tropical disease caused by the parasitic worm Schistosoma japonicum. Among the most serious pathological effects of S. japonicum infection are hepatic lesions (cirrhosis and fibrosis) and portal hypertension. Interleukin-17 (IL-17) is a pro-inflammatory cytokine involved in the pathogenesis of many inflammatory and infectious conditions, including schistosomiasis. We infected C57BL/6 mice with S. japonicum and isolated lymphocytes from the liver to identify cell subsets with high IL-17 expression and release using flow cytometry and ELISA. Expression and release of IL-17 was significantly higher in hepatic lymphocytes from infected mice compared with control mice in response to both non-specific stimulation with anti-CD3 monoclonal antibody plus/anti-CD28 monoclonal antibody and PMA plus ionomycin. We then compared IL-17 expression in three hepatic T-cell subsets, T helper, natural killer T and γδT cells, to determine the major source of IL-17 during infection. Interleukin-17 was induced in all three subsets by PMA + ionomycin, but γδT lymphocytes exhibited the largest increase in expression. We then established a mouse model to further investigate the role of IL-17 in granulomatous and fibrosing inflammation against parasite eggs. Reducing IL-17 activity using anti-IL-17A antibodies decreased infiltration of inflammatory cells and collagen deposition in the livers of infected C57BL/6 mice. The serum levels of soluble egg antigen (IL)-specific IgGs were enhanced by anti-IL-17A monoclonal antibody blockade, suggesting that IL-17 normally serves to suppress this humoral response. These findings suggest that γδT cells are the most IL-17-producing cells and that IL-17 contributes to granulomatous inflammatory and fibrosing reactions in S. japonicum-infected C57BL/6 mouse liver.

Chen D ，Luo X ，Xie H ，Gao Z ，Fang H ，Huang J ... -  《-》

[Immune response of Th17 cells in mesenteric lymph node of mice infected by Schistosoma japonicum].

Luo XP ，Chen DH ，Xie HY ，Gao ZY ，Fang HL ，Huang J ... -  《-》

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

Xie H ，Chen D ，Luo X ，Gao Z ，Fang H ，Huang J ... -  《-》

Dynamics of Th17 cells and their role in Schistosoma japonicum infection in C57BL/6 mice.

Wen X ，He L ，Chi Y ，Zhou S ，Hoellwarth J ，Zhang C ，Zhu J ，Wu C ，Dhesi S ，Wang X ，Liu F ，Su C ... -  《PLoS Neglected Tropical Diseases》