Figure 4
Effect of TIMP-2 antibodies from RA patients on inhibition of MMP9 activity by recombinant TIMP-2. Recombinant matrix metalloproteinase 9 (MMP9) was incubated with mixtures containing (bar 1)immunoglobulin fractions (50 μg) from rheumatoid arthritis (RA) patients possessing antibodies against tissue inhibitor of metalloproteinases-2 (TIMP-2), (bar 2) recombinant TIMP-2 (2.5 ng), (bar 3) TIMP-2/immunoglobulin of RA patients not possessing (n = 2), and (bar 4) possessing TIMP-2 antibodies (n = 2). MMP9 activity was measured as described in Materials and methods. aTIMP, immunoglobulin G containing antibodies against TIMP; contr, control; IgG, immunoglobulin G.