Adjustments of γδ T Cells in the Lung of Schistosoma japonicum-Infected C56BL/6 Mice

Many kinds of lymphocytes are involved in Schistosoma japonicum (S. japonicum) infection-induced disease. gamma delta T cells comprise a small number of innate lymphocytes that quickly respond to foreign materials. In this study, the role of gamma delta T cells in the lung of S. japonicum-infected C56BU6 mice was investigated. The results demonstrated that S. japonicum infection induces gamma delta T cell accumulation in the lung, expressing higher levels of CD25, MHCII, CD80, and PDL1, and lower levels of CD127 and CD62L (P < 0.05). The intracellular cytokines staining results illustrated higher percentages of IL-4-, IL-10-, IL-21-, and IL-6-producing gamma delta T cells and lower percentages of IFN-gamma-expressing gamma delta T cells in the lung of infected mice (P < 0.05). Moreover, the granuloma size in lung tissue was significantly increased in V delta(-/-) mice (P < 0.05). In the lung of S. japonicum-infected V delta(-/-) mice, both type 1 and type 2 immune responses were decreased significantly (P < 0.05). In addition, the expression of CD80 and CD69 on B cells was decreased significantly (P < 0.05), and the SEA-specific antibody was markedly decreased (P < 0.05) in the blood of infected V delta(-/-) mice. In conclusion, this study indicates that gamma delta T cells could adjust the Th2 dominant immune response in the lung of S. japonicum-infected mice.