Figure 1. Role of Th17-type immune responses in intestinal barrier functions and inflammaging. Schematic representation of gut epithelia with diverse cell types. Microbial signals stimulate IL-17/IL-22 cytokine production, and their effector functions on epithelial cells are shown on the left side. Dysfunctional Th17-type immune response results in leaky gut, microbial translocation and inflammation, as shown on the right side. IEC, intestinal epithelial cell; TA, transit amplifying.