MMP expression in rheumatoid inflammation: the rs11568818 polymorphism is associated with MMP-7 expression at an extra-articular site

Genes Immun. 2013 Apr;14(3):162-9. doi: 10.1038/gene.2012.65. Epub 2013 Jan 24.

Abstract

Matrix metalloproteinases (MMPs) contribute to the joint damage in rheumatoid arthritis (RA). Less is known of the involvement of MMPs at extra-articular sites of rheumatoid inflammation. We assessed the relative contribution from MMP-1, MMP-3, MMP-7 and MMP-12 to joint and extra-articular tissue destruction and inflammation by comparing gene expression in joint synovia and subcutaneous rheumatoid nodules from RA patients. Expression of MMP-1 and MMP-3 predominated in synovia, whereas MMP-12 expression was significantly higher in rheumatoid nodules. Markedly higher MMP-7 expression distinguished a subgroup of nodules that featured infiltrating monocyte/macrophage-producing MMP-7 protein. The high MMP-7 expression in nodules was associated with the single-nucleotide polymorphism (SNP) rs11568818 (-181A>G, MMP-7 promoter) and more active inflammation within the nodule lesions. Patients with such nodules had significantly earlier age of RA onset. Our findings indicate that the expression of MMP-1 and MMP-3 occurs relatively independent of the tissue microenvironment with substantial expression also at extra-articular sites. MMP-12 expression reflects the involvement of monocyte/macrophages in rheumatoid inflammation. Evidence for the association between the rs11568818 SNP and increased MMP-7 expression is restricted to nodules, which indicates that consequences of the MMP-7 polymorphism are likely to manifest within aspects of immune/inflammatory activity that are monocyte/macrophage-mediated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Arthritis, Rheumatoid / genetics*
  • Arthritis, Rheumatoid / metabolism
  • Arthritis, Rheumatoid / pathology
  • Female
  • Fluorescent Antibody Technique
  • Gene Expression Regulation, Enzymologic*
  • Humans
  • Macrophages / metabolism
  • Male
  • Matrix Metalloproteinase 1 / genetics*
  • Matrix Metalloproteinase 1 / metabolism
  • Matrix Metalloproteinase 12 / genetics*
  • Matrix Metalloproteinase 12 / metabolism
  • Matrix Metalloproteinase 3 / genetics*
  • Matrix Metalloproteinase 3 / metabolism
  • Matrix Metalloproteinase 7 / genetics*
  • Matrix Metalloproteinase 7 / metabolism
  • Middle Aged
  • Monocytes / metabolism
  • Polymorphism, Single Nucleotide
  • Reverse Transcriptase Polymerase Chain Reaction
  • Rheumatoid Nodule / genetics
  • Rheumatoid Nodule / metabolism
  • Rheumatoid Nodule / pathology
  • Synovial Fluid / metabolism
  • Synovial Membrane / metabolism

Substances

  • Matrix Metalloproteinase 3
  • Matrix Metalloproteinase 7
  • Matrix Metalloproteinase 12
  • Matrix Metalloproteinase 1