Role of polymorphisms in MMP-9 and TIMP-1 as biomarkers for susceptibility to systemic lupus erythematosus patients

Aim: To investigate the possible association between MMP-9 (-1562 C/T) and TIMP-1 (372 T/C) polymorphism and inflammatory markers with disease activity in systemic lupus erythematosus (SLE) patients. Materials & methods: 150 SLE patients were recruited. Disease severity was assessed by SLEDAI (SLE disease activity index). The polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and serum levels by ELISA. Results: Among patients mean MMP-9 serum levels and mRNA expression were significantly decreased with increase in TIMP-1 levels (p <0.0001). Concomitant presence of both MMP-9 1562 T and TIMP-1 372 C alleles synergistically increased risk of SLE by 7.89-fold (p <0.0001). The mRNA expression of MMP-9 and TIMP-1 correlated with SLEDAI score. Conclusion: MMP-9, TIMP-1 and MMP-9/TIMP-1 ratios may act as biomarkers for susceptibility to SLE.