Figure 2
Role of T helper-17 (Th17) cytokines in protective immunity at the mucosa. Infection-induced interleukin (IL)-17 and IL-22 can be produced by several immune cells found in mucosal sites. A critical likely target of IL-17 and IL-22 is the mucosal epithelium, in which IL-17 augments granulocyte colony-stimulating factor (G-CSF) and CXC chemokine production, resulting in the recruitment of neutrophils that contribute to bacterial and fungal clearance at mucosal sites. IL-22 along with IL-17 also augments antimicrobial peptides and epithelial repair function important for control of extracellular fungal pathogens. In the setting of vaccine-induced immunity, Th17 cells can induce the production of ligands for CXCR3 and augment the recruitment of interferon-γ (IFN-γ)-producing Th1 cells to control intracellular pathogen growth.
