Oncostatin M decreases interleukin-1 β secretion by human synovial fibroblasts and attenuates an acute inflammatory reaction in vivo.
Bottom Line: Signal transducer and activator of transcription-1 appeared to mediate the effects of OSM on stimulated human synovial fibroblasts.In the murine dorsal air pouch model of inflammation, OSM reduced the expression of the pro-inflammatory cytokines IL-1β and TNF-α in lining tissues, and their presence in the cavity.These results as a whole suggest an anti-inflammatory role for OSM, guiding inflammatory processes towards resolution.
Affiliation: Centre de Recherche en Rhumatologie et Immunologie du CHUQ, and Department of Microbiology-Infectiology and Immunology, Faculty of Medicine, Laval University, Quebec City, QC, Canada.Show MeSH
Related in: MedlinePlus
Mentions: To ascertain that the activities of recombinant OSM were not merely a result of its source, we sought to determine the impact of native, endogenous OSM on the cytokine expression profile of HSFs. We stimulated freshly isolated human PMNs with LPS and GM-CSF, a condition known to induce OSM secretion in these cells . Stimulations were performed in presence of ADA (0.1 U/ml), a condition which prevents accumulation of endogenous adenosine in cell suspensions, thus eliminating the well-documented modulating effects of adenosine on neutrophil activation [32-34]. We thus obtained OSM concentrations of about 4 ng/ml (based on ELISA) in supernatants of PMN cell suspensions (Fig. 2A) and used these supernatants to stimulate HSFs in culture. Supernatants from resting PMNs were used as control. Fold increases in gene expression were as follows: 14.4 ± 3 for IL-1β, 38.9 ± 7.9 for IL-6, 35.7 ± 9.3 for CXCL8 and 6.2 ± 0.4 for CCL2 (mean ± S.E.M., n ∇ 6, not shown). Adding neutralizing anti-OSM antibody to the supernatant caused levels of IL-1β mRNA to double, while significantly decreasing those of IL-6 and CCL2 (Fig. 2B) and slightly increasing CXCL8 mRNA. At the level of cytokine secretion, the anti-OSM antibody had a similar impact, causing IL-1β concentrations to double (Fig. 2C), while decreasing that of IL-6 and CCL2 by more than 50%. The antibody also increased CXCL8 secretion. These results corroborate those obtained with recombinant OSM, thereby confirming that both OSM sources share comparable pro-resolution properties, notably by modulating the expression of inflammatory genes, including IL-1β, in HSFs.
Affiliation: Centre de Recherche en Rhumatologie et Immunologie du CHUQ, and Department of Microbiology-Infectiology and Immunology, Faculty of Medicine, Laval University, Quebec City, QC, Canada.