Increased interleukin-17 production via a phosphoinositide 3-kinase/Akt and nuclear factor kappaB-dependent pathway in patients with rheumatoid arthritis.
Inflammatory mediators have been recognized as being important in the pathogenesis of rheumatoid arthritis (RA). Interleukin (IL)-17 is an important regulator of immune and inflammatory responses, including the induction of proinflammatory cytokines and osteoclastic bone resorption. Evidence for the expression and proinflammatory activity of IL-17 has been demonstrated in RA synovium and in animal models of RA. Although some cytokines (IL-15 and IL-23) have been reported to regulate IL-17 production, the intracellular signaling pathways that regulate IL-17 production remain unknown. In the present study, we investigated the role of the phosphoinositide 3-kinase (PI3K)/Akt pathway in the regulation of IL-17 production in RA. Peripheral blood mononuclear cells (PBMC) from patients with RA (n = 24) were separated, then stimulated with various agents including anti-CD3, anti-CD28, phytohemagglutinin (PHA) and several inflammatory cytokines and chemokines. IL-17 levels were determined by sandwich enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction. The production of IL-17 was significantly increased in cells treated with anti-CD3 antibody with or without anti-CD28 and PHA (P < 0.05). Among tested cytokines and chemokines, IL-15, monocyte chemoattractant protein-1 and IL-6 upregulated IL-17 production (P < 0.05), whereas tumor necrosis factor-alpha, IL-1beta, IL-18 or transforming growth factor-beta did not. IL-17 was also detected in the PBMC of patients with osteoarthritis, but their expression levels were much lower than those of RA PBMC. Anti-CD3 antibody activated the PI3K/Akt pathway; activation of this pathway resulted in a pronounced augmentation of nuclear factor kappaB (NF-kappaB) DNA-binding activity. IL-17 production by activated RA PBMC is completely or partly blocked in the presence of the NF-kappaB inhibitor pyrrolidine dithiocarbamate and the PI3K/Akt inhibitor wortmannin and LY294002, respectively. However, inhibition of activator protein-1 and extracellular signal-regulated kinase 1/2 did not affect IL-17 production. These results suggest that signal transduction pathways dependent on PI3K/Akt and NF-kappaB are involved in the overproduction of the key inflammatory cytokine IL-17 in RA.
Kim
Kyoung-Woon
KW
Department of Medicine, Division of Rheumatology, The Center for Rheumatic Diseases, and The Rheumatism Research Center (RhRC), Catholic Research Institutes of Medical Sciences, Catholic University of Korea, Seoul, Korea. woon1212@catholic.ac.kr
Cho
Mi-La
ML
Park
Mi-Kyung
MK
Yoon
Chong-Hyeon
CH
Park
Sung-Hwan
SH
Lee
Sang-Heon
SH
Kim
Ho-Youn
HY
D000328:Adult; D000368:Aged; D000730:Androstadienes / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D001172:Arthritis, Rheumatoid / Q000378:metabolism*; D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D018925:Chemokines / Q000494:pharmacology; D002867:Chromones / Q000494:pharmacology; D016207:Cytokines / Q000494:pharmacology; D005260:Female; D005419:Flavonoids / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D020381:Interleukin-17 / Q000096:biosynthesis* / Q000235:genetics; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009025:Morpholines / Q000494:pharmacology; D016328:NF-kappa B / Q000502:physiology*; D010003:Osteoarthritis / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D051057:Proto-Oncogene Proteins c-akt / Q000502:physiology*; D011725:Pyridines / Q000494:pharmacology; D011759:Pyrrolidines / Q000494:pharmacology; D011994:Recombinant Proteins / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology; D013859:Thiocarbamates / Q000494:pharmacology; D000077191:Wortmannin
D000730:Androstadienes; D000911:Antibodies, Monoclonal; D018106:CD28 Antigens; D017252:CD3 Complex; D018925:Chemokines; D002867:Chromones; D016207:Cytokines; D005419:Flavonoids; D007093:Imidazoles; D020381:Interleukin-17; D009025:Morpholines; D016328:NF-kappa B; D010835:Phytohemagglutinins; D011725:Pyridines; D011759:Pyrrolidines; D011994:Recombinant Proteins; D013859:Thiocarbamates; C020972:pyrrolidine dithiocarbamic acid; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; D019869:Phosphatidylinositol 3-Kinases; C494918:AKT1 protein, human; D051057:Proto-Oncogene Proteins c-akt; C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one; D000077191:Wortmannin