CCL20 and infection: Prevotella mainly binds to TLR2 to stimulate antigen‐presenting cells and airway epithelial cells to release IL‐23, IL‐1, IL‐8, IL‐6, CCL20, and other cytokines; recruit neutrophils; and activate Th17‐related immune responses, which are involved in establishing lung tolerance and improving respiratory tract anti‐infection ability.49, 106