Research Note: Expression of T cell-related cytokines in chicken cecal and spleen tissues following Eimeria tenella infection in vivo
Hailiang Yu, Wenbin Zou, Changhao Mi, Qi Wang, Guojun Dai, Tao Zhang, Genxi Zhang, Kaizhou Xie, Jinyu Wang, Huiqiang Shi
Abstract
The T cell-mediated immune response plays an important role in coccidiosis. To reveal the host T cell immune response following Eimeria tenella (E. tenella) infection in chickens, we performed quantitative real-time PCR to analyze the dynamic expression of the Th1-related cytokines IFN-γ, IL-2, and IL-12; the Th17-related cytokines IL-17A, IL-17F, and IL-22; and the Treg-related cytokines IL-10, TGF-β, and CTLA-4 in the cecum and spleen at 0, 2, 4, 6, 8, and 10 d postinfection (dpi). In the cecal tissue, the expression of the Th1-related cytokine IFN-γ was significantly higher at 6 and 8 dpi than at other time points (11.97-fold and 39.78-fold, respectively, compared with 0 dpi, P < 0.05). IL-2 and IL-12 expression was significantly higher at 6 and 8 dpi than at 0, 2 and 10 dpi (P < 0.05). The expression of the Th17-related cytokines IL-17A and IL-17F at 2 and 4 dpi and IL-22 expression at 4 dpi were significantly higher than those at 0, 6, 8 and 10 dpi (P < 0.05). The expression of the Treg-related cytokines IL-10, TGF-β and CTLA-4 was significantly higher at 6 and 8 dpi than at 0, 2 and 4 dpi (P < 0.05). In the spleen, IFN-γ and IL-12 expression peaked at 4 dpi, while IL-2 expression peaked at 10 dpi. IL-17A, IL-17F and IL-22 expression was significantly higher at 2 and 4 dpi than at 0, 6, 8 and 10 dpi (P < 0.05). Treg-related cytokine TGF-β expression was almost unchanged and significantly decreased at only 4 dpi (P < 0.05), while CTLA-4 expression showed an overall decreasing trend from 0 to 8 dpi but increased significantly at 10 dpi (P < 0.05). The expression patterns of three T cell subset-related cytokines were different in the cecum and spleen. Furthermore, Th1 and Treg cells participate in the immune response mainly in the latter stage of coccidia infection (6 and 8 dpi), while Th17 cells play a role mainly in the early stages of infection (2 and 4 dpi). Our data will help to deepen the understanding of the complex T cell immune response after coccidia infection.