Th17, intestinal microbiota and the abnormal immune response in the pathogenesis of celiac disease

Celiac disease (CD) is an autoimmune enteropathy induced by the ingestion of gluten in genetically predisposed individuals who carry the HLA-DQ2 or -DQ8 alleles. The immune response is abnormal in celiac disease with small intestinal epithelial damage via CD8+CD4- intraepithelial lymphocytes. The etiology is multifactorial involving genetic and environmental factors, an abnormal immune response, and intestinal dysbiosis. The innate and acquired T-cell mediated immunity play important roles in the pathogenesis of this disease, particularly CD4+ Th17 cells, which have been shown to have critical functions in host defense against bacterial pathogens and in the inflammatory responses to deamidated gluten peptides. We review what is known about the interaction between immune system and intestinal microbiota in the pathogenesis of celiac disease.