Recent progress in understanding host immune response to Avian Coccidiosis: Th1 and Th17 responses

Authors: KIM, WOOHYUN - Gyeongsang National University; Lillehoj, Hyun

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/2/2017
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Coccidiosis is one of the most economically important diseases of chickens caused by Eimeria spp. since it destroys the intestinal epithelium resulting in nutrient malabsorption, body weight loss, and in severe cases, death. Since the life cycle of Eimeria parasites is complex and comprised of intracellular, extracellular, asexual, and sexual stages, host immune responses are quite diverse and complex. In the context of adaptive T cell immunity, it has been shown that IFN-'-mediated Th1 response is dominant in Eimeria infection. However, since the discovery of Th17 type response which is distinct from the Th1 and Th2 responses, it has become evident that Th17 cells may play an important role in the host defense against various infections including parasitic infections. In order to determine if Th17 type response is also induced in chickens and its potential role in host response to coccidiosis, we investigated the expression levels of Th17 cells-related cytokines in E. tenella-infected chickens along with Th1 cells-related cytokines. Our recent studies showed that an increase of both CD4+IFN-'+ and CD4+IL-17A+ cells in the E. tenella-infected cecum with increasing numbers of parasites in the feces. We also found that the mRNA levels of IL-17A and IFN-' increased in the Eimeria antigen-stimulated splenic CD4+ cells and these results suggest that the Th1- and Th17-associated cytokines are enhanced in Eimeria-infected tissues. Collectively, our study demonstrates that the Th17 as well as Th1 immune responses are implicated in host immune response to E. tenella infection in chickens.