Interleukin-17 as an effector molecule of innate and acquired immunity against infections.
Interleukin (IL)-17 is a proinflammatory cytokine which induces differentiation and migration of neutrophils through induction of cytokines and chemokines including granulocyte-colony stimulating factor and CXCL8/IL-8. IL-17-producing CD4(+) T cells (Th17) have pivotal role in pathogenesis of autoimmune diseases. IL-17 is also involved in protective immunity against various infections. IL-17 has important role in induction of neutrophil-mediated protective immune response against extracellular bacterial or fungal pathogens such as Klebsiella pneumoniae and Candida albicans. Importance of IL-17 in protection against intracellular pathogens including Mycobacterium has also been reported. Interestingly, not only CD4(+) T cells but atypical CD4(-)CD8(-) T cells expressing T cell receptor (TCR) gammadelta produce IL-17, and IL-17 producing cells participate in both innate and acquired immune response to infections. Furthermore, neutrophil induction may not be the only mechanism of IL-17-mediated protective immunity. IL-17 seems to participate in host defense through regulation of cell-mediated immunity or induction of antimicrobial peptides such as beta-defensins. In this review, we summarize recent progress on the role of IL-17 in immune response against infections, and discuss possible application of IL-17 in prevention and treatment of infectious diseases.
Matsuzaki
Goro
G
Molecular Microbiology Group, Center of Molecular Biosciences, University of the Ryukyus, Nishihara, Okinawa, Japan. matsuzak@comb.u-ryukyu.ac.jp
Umemura
Masayuki
M
D000818:Animals; D001424:Bacterial Infections / Q000276:immunology* / Q000517:prevention & control*; D006801:Humans; D020381:Interleukin-17 / Q000276:immunology*; D009181:Mycoses / Q000276:immunology* / Q000517:prevention & control*; D009504:Neutrophils / Q000276:immunology*
D020381:Interleukin-17