MMP1 and rheumatoid arthritis: MMP and TIMP expression increased not only in tissues but also in the peripheral blood samples from patients with acute coronary syndrome, cancer, hepatitis, rheumatoid arthritis, and normal persons.[11–15] Wiercinska-Drapalo A et al. [8] used ELISA to determine MMP-1 and TIMP-1 expression and found that serum MMP-1 and TIMP-1 were significantly increased in patients with UC compared with normal controls.