IL17A and infection: IL-17 and IL-23 expression is considered as a marker of Th17 response, Th17 cells are a crucial modulator of adaptive immunity against Leishmania parasites to recruit neutrophil to the infection site and to play a dual role at the site of infection [21].Therefor, our results indicate that not only Th1/Th2, but also Th17 are involved in the protective immunity against Leishmania infection, which is possibly involved in the immunopathology and tissue damage in the Leishmania-triggered HLH.