• Molecules and Cells
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• 제19권2호
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• pp.180-184
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• 2005

IL-17 is a major proinflammatory cytokine secreted by activated T-lymphocytes that accumulates in the inflamed joints of rheumatoid arthritis (RA) patients. Additional IL-17-related molecules and their receptors have been discovered and may also contribute to RA pathogenesis. We examined the expression of the prototypic IL-17 (IL-17A) and its homologs, IL-17B-F, by RT-PCR analyses of synovial fluid mononuclear cells (SFMCs) and peripheral blood mononuclear cells (PBMCs) from RA patients. We also tested for induction of the IL-17 receptor homologs upon stimulation of the fibroblast-like synoviocytes (FLSs) of RA patients with IL-17. The patients' SFMCs expressed IL-17C, E and F in addition to IL-17A. As in the case of IL-17, IL-15 appears to be the major inducer of these homologs in RA SFMCs. We detected transcripts of IL-17R, as well as those of IL-17RB, C and D, in the FLSs of RA patients. Whereas IL-17R expression increased upon in vitro stimulation with IL-17, expression of IL-17RB, C and D was unchanged. However the possibility of cross-interaction between other IL-17 homologs and receptor isoforms remains to be investigated. Our data suggest that these additional homologs should also be considered as targets for immune modulation in the treatment of RA joint inflammation.

• Journal of Microbiology and Biotechnology
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• 제9권1호
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• pp.106-112
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• 1999

The therapeutic potential of phosphodiesterase 4(PDE4) inhibitors in inflammatory diseases including some autoimmune diseases has been explored recently with some hopeful results. These PDE4 inhibitors are thought to show their anti-inflammatory effect by down-regulating tumor necrosis factor-a (TNF-$\alpha$) production in lymphocytes and macrophages. A high concentration of TNF-$\alpha$has been found in rheumatoid arthritis (RA) synovium and reducing TNF-$\alpha$using biological agents was proven to be an effective RA treatment. To test the possibility of using PDE4 inhibitors for RA treatment, the effects of a newly synthesized PDE4 inhibitor, DWP205505, on TNF-$\alpha$ and IL-10 production was tested in cells isolated from normal peripheral blood and rheumatoid arthritis synovial fluid. Cytokine production was assayed at the protein level by sandwich enzyme-linked immunosorbent assay (ELISA) and at the mRNA expression level by semi-quantitative RT-PCR. Another PDE4 inhibitor, RP73401, was used for comparison. DWP205505 and RP73401 had no harmful effect on cell viability up to 10 $\mu$M concentration during the 24 h culture period. DWP205505 as well as RP73401 significantly reduced TNF-$\alpha$ secretion from lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (pBMC) and synovial fluid mononuclear cells (SFMC). The effect of DWP205505 or RP73401 treatment on the mRNA expression of TNF-$\alpha$ was also studied in LPS-stimulated PBMC and SFMC. TNF-$\alpha$ mRNA expression was increased by LPS stimulation and both of the PDE4 inhibitors suppressed TNF-$\alpha$ mRNA expression. For interleukin-l0 (IL-l0), a little different results were obtained from PBMC and SFMC; IL-l0 secretion was unaffected by LPS stimulation and only minimally affected by both of the PDE4 inhibitors in PBMC. In unstimulated SFMC, DWP205505 and RP73401 slightly enhanced IL-10 secretion, while they reduced IL-l0 secretion from LPS-stimulated SFMC where IL-l0 secretion was a lot higher than unstimulated SFMC. These results suggest that the newly synthesized PDE4 inhibitor DWP205505 may have anti-rheumatoid arthritis activity.