Open AccessCXCR2‐specific chemokines mediate leukotriene B 4 –dependent recruitment of neutrophils to inflamed joints in mice with antigen‐induced arthritis
Author(s) -
Grespan Renata,
Fukada Sandra Y.,
Lemos Henrique P.,
Vieira Silvio M.,
Napimoga Marcelo H.,
Teixeira Mauro M.,
Fraser Alasdair R.,
Liew Foo Y.,
McInnes Iain B.,
Cunha Fernando Q.
Publication year - 2008
Publication title -
arthritis & rheumatism
Language(s) - English
Resource type - Journals
eISSN - 1529-0131
pISSN - 0004-3591
DOI - 10.1002/art.23597
Subject(s) - cxcl1 , synovial fluid , cxcl5 , cxc chemokine receptors , synovitis , arthritis , immunology , chemokine , medicine , rheumatoid arthritis , leukotriene b4 , chemistry , osteoarthritis , inflammation , pathology , chemokine receptor , alternative medicine
Objective To investigate the mechanism underlying neutrophil migration into the articular cavity in experimental arthritis and, by extension, human inflammatory synovitis. Methods Antigen‐induced arthritis (AIA) was generated in mice with methylated bovine serum albumin (mBSA). Migration assays and histologic analysis were used to evaluate neutrophil recruitment to knee joints. Levels of inflammatory mediators were measured by enzyme‐linked immunosorbent assay. Antibodies and pharmacologic inhibitors were used in vivo to determine the role of specific disease mediators. Samples of synovial tissue and synovial fluid from rheumatoid arthritis (RA) or osteoarthritis patients were evaluated for CXCL1 and CXCL5 expression. Results High levels of CXCL1, CXCL5, and leukotriene B 4 (LTB 4 ) were expressed in the joints of arthritic mice. Confirming their respective functional roles, repertaxin (a CXCR1/CXCR2 receptor antagonist), anti‐CXCL1 antibody, anti‐CXCL5 antibody, and MK886 (a leukotriene synthesis inhibitor) reduced mBSA‐induced neutrophil migration to knee joints. Repertaxin reduced LTB 4 production in joint tissue, and neutrophil recruitment induced by CXCL1 or CXCL5 was inhibited by MK886, suggesting a sequential mechanism. Levels of both CXCL1 and CXCL5 were elevated in synovial fluid and were released in vitro by RA synovial tissues. Moreover, RA synovial fluid neutrophils stimulated with CXCL1 or CXCL5 released significant amounts of LTB 4 . Conclusion Our data implicate CXCL1, CXCL5, and LTB 4 , acting sequentially, in neutrophil migration in AIA. Elevated levels of CXCL1 and CXCL5 in the synovial compartment of RA patients provide robust comparative data indicating that this mechanism plays a role in inflammatory joint disease. Together, these results suggest that inhibition of CXCL1, CXCL5, or LTB 4 may represent a potential therapeutic strategy in RA.