Th17 cells at the crossroads of innate and adaptive immunity against infectious diseases at the mucosa

Abstract

T helper type 17 (Th17) cells are a distinct lineage of T cells that produce the effector molecules IL-17, IL-17F, IL-21 and IL-22. Although the role of Th17 cells in autoimmunity is well documented, there is growing evidence that the Th17 lineage and other IL-17 producing cells are critical for host defense against bacterial, fungal and viral infections at mucosal surfaces. Here we summarize recent progress in our understanding of the function of IL-17 producing cells as a bridge between innate and adaptive immunity against infectious diseases at the mucosa.

The Special Relationship in the Development and Function of T Helper 17 and Regulatory T Cells

“…[86][87][88] In addition, IL-22 also induces epithelial proliferation via STAT3 signaling, which facilitate wound healing and recovery from pathological damaged caused by inflammation. 89 In response to self-produced IL-21, Th17 cells in turn expand during pathogen infection, which will boost the pathogen-specific Th17 cell response.…”

Helper T-Cell Type 17 Cytokines and Immunity in the Lung

“…For example, Th1 cells and their signature cytokine IFN-g were critical for granuloma infection and host immunity against intracellular pathogens such as Mycobacteria tuberculosis and Listeria monocytogenes (4). Th2 cells, on the other hand, were required for expulsion of helminthic infection (4). So what about Pneumocystis?…”

Natural Occurring IL-17 Producing T Cells Regulate the Initial Phase of Neutrophil Mediated Airway Responses

“…Recently, a new subset of helper T cells, Th17, which produces IL-17A, IL-17F, IL-10, IL-21, and IL-22, but not the cytokines produced by Th1 or Th2 cells, has been identified. Th17 cells appear to be responsible for the regulation of adaptive immunity against Dectin-mediated fungal infections, such as Pneumocystis carinii (1)(2)(3), and several TLRs regulates the development of Th17 cells (4). IL-17 is also known to be a critical cytokine for regulating inflammatory responses, and its expression is tightly associated with pathogenesis in autoimmune disorders, such as multiple sclerosis and collagen-induced arthritis (5,6).…”