Matrix metalloproteinase-9 and its natural inhibitor TIMP-1 expressed or secreted by peripheral blood mononuclear cells from patients with systemic lupus erythematosus

J Autoimmun. 2003 Jun;20(4):323-31. doi: 10.1016/s0896-8411(03)00037-4.


Matrix metalloproteinase-9 (MMP-9) was involved in inflammation and immune system dysfunctions. Besides immunologic abnormalities, systemic lupus erythematosus (SLE) also presents chronic inflammatory components. Therefore, a role of MMP-9 in SLE pathology might be supposed. To verify this hypothesis, SLE patients and healthy donors were compared for the MMP-9 and MMP-9 mRNA levels in peripheral blood mononuclear cells (PBMCs), the spontaneous secretion of MMP-9 and TIMP-1 and the MMP-9 activity. Thus, we found that fresh PBMCs from SLE patients expressed a significantly higher activity of MMP-9 and spontaneously released higher levels of MMP-9, as compared to healthy donors, while the secreted TIMP-1 level was the same for both groups. When the patients were sub-grouped based on disease status, the most increased pro-MMP-9 activity inside the PBMCs was identified for relapse SLE sub-group. A similar observation for SLE patients with positive serum fibrinogen was found. Following culture, the PBMCs from remission SLE patients secreted significantly higher MMP-9 level, than the PBMCs from relapse SLE patients. PBMCs from relapse SLE patients secreted the highest levels of TIMP-1, although this difference was not statistically significant. Taken together, these observations suggested the multiple roles of MMP-9 and TIMP-1 in progress of inflammation and tissue damage and/or in repair, depending on clinical stages of SLE.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autoimmunity
  • Base Sequence
  • Case-Control Studies
  • Female
  • Humans
  • Inflammation Mediators / blood
  • Leukocytes, Mononuclear / metabolism
  • Lupus Erythematosus, Systemic / blood*
  • Lupus Erythematosus, Systemic / genetics
  • Lupus Erythematosus, Systemic / immunology
  • Matrix Metalloproteinase 9 / blood*
  • Matrix Metalloproteinase 9 / genetics
  • Middle Aged
  • RNA, Messenger / blood
  • RNA, Messenger / genetics
  • Tissue Inhibitor of Metalloproteinase-1 / blood*


  • Inflammation Mediators
  • RNA, Messenger
  • Tissue Inhibitor of Metalloproteinase-1
  • Matrix Metalloproteinase 9