The Balance of Tissue Inhibitor of Metalloproteinase-1 and Matrix Metalloproteinase-9 in the Autoimmune Inner Ear Disease Patients

Tissue inhibitor of metalloproteinase-1 (TIMP-1) is a protein implicated in the control of inflammation in a number of autoimmune diseases. We hypothesized that the balance of TIMP-1 and matrix metalloproteinase-9 (MMP-9) may influence the control or perpetuation of inflammation in corticosteroid-responsive (RES) and corticosteroid-resistant (NR) autoimmune inner ear disease (AIED) patients. In the present study, we observed that plasma from AIED patients exhibited greater levels of TIMP-1 values compared with normal healthy controls. TIMP-1 abrogates lipopolysaccharide-mediated interleukin (IL)-1β release from peripheral blood mononuclear cells in a dose-dependent manner. RES AIED patients have higher basal TIMP-1 levels and produce more TIMP-1 in response to IL-1β. Conversely, consistent with our previous studies, we found that NR patients have higher basal MMP-9 levels and produce more MMP-9 levels in response to IL-1β.