Th17 cells are associated with the Th1/Th2‑cell balance during Echinococcus multilocularis infection.

The present study investigated the immunopathological effect of Echinococcus multilocularis (Em) using cytokine detection. Expression of the T-helper (Th) 17-cytokine, interleukin 17 (IL-17), was observed using immunohistochemical staining, and levels of cytokines, including IL-17, transforming growth factor beta 1 (TGF-beta 1), IL-6, interferon gamma (IFN-gamma) and IL-4, were assessed using ELISA at different stages of infection. IL-17 expression occurred in hepatic cells at 1 month post-infection, reached a maximum at 3 months post-infection and then decreased gradually. Compared with the uninfected control, levels of the cytokines IL-17, TGF-beta 1, IL-6, IFN-gamma and IL-4 exhibited different dynamic patterns when infected with Em. In the immune response during the whole infection period, Th17 cells play an important role by secreting IL-17, which may be involved in the Th1/Th2-cell balance during the immune response. Th17 cells are associated with immunopathology in Em infection.