Anti-inflammatory effects of IL-17A on Helicobacter pylori-induced gastritis.
Helicobacter pylori-induced immune responses are skewed toward a T helper (Th) 1 phenotype. IL-17-producing Th17 cells have recently been discovered, and we examined the role of IL-17A in H. pylori-induced gastritis. Six months after inoculation with H. pylori, the mice received an intraperitoneal injection of recombinant IL-17A, anti-IL-17A antibody or irrelevant IgG(2a) for 3days. H. pylori infection markedly increased mRNA for IL-17A. Double immunofluorescence studies showed that IL-17A proteins were expressed on CD4(+) T cells, macrophages, and dendritic cells. H. pylori infection elevated mRNAs for IL-12, IFN-gamma, and TNF-alpha with increase in myeloperoxidase activity, whereas it did not affect mRNAs for IL-4 and IL-5. Neutralization of IL-17A elevated mRNAs for IFN-gamma and TNF-alpha, and myeloperoxidase activity, whereas recombinant IL-17A had a tendency to reduce these parameters. In conclusion, IL-17A exerts anti-inflammatory effects on H. pylori-induced gastritis through suppression of Th1 differentiation.
Otani
Koji
K
Department of Gastroenterology, Osaka City University Graduate School of Medicine, Osaka, Japan. kojiotani@med.osaka-cu.ac.jp
Watanabe
Toshio
T
Tanigawa
Tetsuya
T
Okazaki
Hirotoshi
H
Yamagami
Hirokazu
H
Watanabe
Kenji
K
Tominaga
Kazunari
K
Fujiwara
Yasuhiro
Y
Oshitani
Nobuhide
N
Arakawa
Tetsuo
T
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage; D005756:Gastritis / Q000276:immunology* / Q000382:microbiology; D016481:Helicobacter Infections / Q000150:complications*; D016480:Helicobacter pylori / Q000276:immunology*; D007108:Immune Tolerance; D020381:Interleukin-17 / Q000008:administration & dosage / Q000096:biosynthesis* / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000096:biosynthesis / Q000235:genetics; D018417:Th1 Cells / Q000187:drug effects / Q000276:immunology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D020381:Interleukin-17; D011994:Recombinant Proteins