In:
Annals of the Rheumatic Diseases, BMJ, Vol. 71, No. 1 ( 2012-01), p. 150-154
Abstract:
Interleukin (IL) 34 is a new cytokine implicated in macrophage differentiation and osteoclastogenesis. This study assessed IL-34 expression in the tissue of patients with rheumatoid arthritis (RA). Methods Immunohistochemistry was performed in synovial biopsies from patients with RA (n=20), osteoarthritis (n=3) or other inflammatory arthritis (n=4). IL-34 was detected in the synovial fluid by ELISA and its messenger RNA expression was studied by quantitative PCR in rheumatoid synovial fibroblasts after stimulation by tumour necrosis factor α (TNFα) and IL-1β. Wild-type, jnk1 −/− –jnk2 −/− and nemo −/− murine fibroblasts and pharmacological inhibition were used to determine the involvement of nuclear factor kappa B (NF-κB) and JNK in that effect. Results IL-34 was expressed in 24/27 biopsies, with three samples from RA patients being negative. A significant association was found between IL-34 expression and synovitis severity. Levels of IL-34 and the total leucocyte count in synovial fluid were correlated. TNFα and IL-1β stimulated IL-34 expression by synovial fibroblasts in a dose/time-dependent manner through the NF-κB and JNK pathway. Conclusion This work for the first time identifies IL-34 expression in the synovial tissue of patients with arthritis. This cytokine, as a downstream effector of TNFα and IL-1β, may contribute to inflammation and bone erosions in RA.
Type of Medium:
Online Resource
ISSN:
0003-4967
,
1468-2060
DOI:
10.1136/annrheumdis-2011-200096
Language:
English
Publisher:
BMJ
Publication Date:
2012
detail.hit.zdb_id:
1481557-6
detail.hit.zdb_id:
7090-7
Permalink