IL-17-mediated regulation of innate and acquired immune response against pulmonary Mycobacterium bovis bacille Calmette-Guerin infection.
IL-17 is a cytokine that induces neutrophil-mediated inflammation, but its role in protective immunity against intracellular bacterial infection remains unclear. In the present study, we demonstrate that IL-17 is an important cytokine not only in the early neutrophil-mediated inflammatory response, but also in T cell-mediated IFN-gamma production and granuloma formation in response to pulmonary infection by Mycobacterium bovis bacille Calmette-Guérin (BCG). IL-17 expression in the BCG-infected lung was detected from the first day after infection and the expression depended on IL-23. Our observations indicated that gammadelta T cells are a primary source of IL-17. Lung-infiltrating T cells of IL-17-deficient mice produced less IFN-gamma in comparison to those from wild-type mice 4 wk after BCG infection. Impaired granuloma formation was also observed in the infected lungs of IL-17-deficient mice, which is consistent with the decreased delayed-type hypersensitivity response of the infected mice against mycobacterial Ag. These data suggest that IL-17 is an important cytokine in the induction of optimal Th1 response and protective immunity against mycobacterial infection.
Umemura
Masayuki
M
Molecular Microbiology Group, Center of Molecular Biosciences, University of the Ryukyus, 1 Senbaru, Nishihara, Okinawa 903-0213, Japan. umemura@comb.u-ryukyu.ac.jp
Yahagi
Ayano
A
Hamada
Satoru
S
Begum
Mst Dilara
MD
Watanabe
Hisami
H
Kawakami
Kazuyoshi
K
Suda
Takashi
T
Sudo
Katsuko
K
Nakae
Susumu
S
Iwakura
Yoichiro
Y
Matsuzaki
Goro
G
D000818:Animals; D016207:Cytokines / Q000276:immunology; D006968:Hypersensitivity, Delayed / Q000235:genetics / Q000276:immunology / Q000473:pathology; D007111:Immunity, Cellular; D007113:Immunity, Innate / Q000235:genetics; D007249:Inflammation / Q000235:genetics / Q000276:immunology / Q000473:pathology; D020381:Interleukin-17 / Q000172:deficiency / Q000276:immunology*; D051379:Mice; D009163:Mycobacterium bovis / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology / Q000473:pathology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology* / Q000473:pathology; D013997:Time Factors; D014375:Tuberculoma / Q000235:genetics / Q000276:immunology* / Q000473:pathology / Q000662:veterinary; D014397:Tuberculosis, Pulmonary / Q000235:genetics / Q000276:immunology* / Q000662:veterinary
D016207:Cytokines; D020381:Interleukin-17; D016692:Receptors, Antigen, T-Cell, gamma-delta