Cryptosporidium parvum commonly inhabits the intestinal tract of animals and humans and can cause acute watery diarrhea and weight loss. However, host immune responses to Cryptosporidium infections are not fully understood. IL-17 (also called IL-17A) is a pro-inflammatory cytokine of Th17 cells that plays a role in the host response to Cryptosporidium baileyi infection. The present study examined levels of IL-17-specific messenger RNA (mRNA) and Th17 associating cytokines in C. parvum-infected immune-suppressed BALB/c mice using real-time quantitative PCR (qPCR). Levels of IL-17 protein were determined by ELISA. The results showed that levels of IL-17 mRNA and Th17 cell-related cytokines, namely TGF-β, IL-6, STAT-3, RORγt, IL-22, TNF-α, and IL-23, were significantly increased (P < 0.05) in gut-associated lymphoid tissue (GALT) and spleen. IL-17 protein levels in GALT were also significantly increased (P < 0.05) after infection. The present study suggested that Th17 cells play a role in host-C. parvum interaction. These results could inform future studies of the immune response against C. parvum infection in transient immunosuppressed populations.
Keywords: Cryptosporidium parvum; Cytokines; GALT; IL-17; Mice.