Serum levels of matrix metalloproteinases in patients with idiopathic pulmonary fibrosis and their clinical value

Abstract

Objective To investigate serum levels of matrix metalloproteinase (MMP)-1, -2 and -9 in patients with idiopathic pulmonary fibrosis (IPF), and to assess their clinical value. Methods 39 clinically confirmed IPF cases and 36 healthy controls were recruited. A sample of 5 ml peripheral blood was collected from each individual and serum levels of MMP-1, -2 and -9 were detected by the enzyme-linked immunosorbent assay.Forced vital capacity (FVC) and diffusing capacity of carbon monoxide (DLCO) were measured in IPF patients. Serum levels of MMP-1, -2 and -9 were compared between the groups. The correlations between serum levels of MMPs and lung function indicators were analyzed. Results The median serum levels of MMP-1, MMP-2 and MMP-9 were higher in the IPF group than in the control group〔906.30 (613.50-1139.23) μg/L vs. 808.38 (596.59-1249.36) μg/L, 9.13 (5.95-11.92) μg/L vs. 7.72 (5.28-10.35) μg/L, 14.56 (8.24-18.96) μg/L vs. 11.38 (8.07-17.14) μg/L, Z=-2.397, -3.564, -4.152, respectively, P=0.017, 0.000, 0.000〕. In patients with IPF, the serum level of MMP-2 was negatively correlated with DLCO% (r=-0.53, P=0.011) and the serum level of MMP-9 had a negative correlation with FVC% (r=-0.49, P=0.020) and DLCO% (r=-0.58, P=0.005). Conclusions Taken together, serum MMP-1 , MMP-2 and MMP-9 levels may help in the clinical diagnosis of IPF. MMP-2 and MMP-9 may be important biomarkers to predict the prognosis of IPF. Key words: Pulmonary fibrosis; Matrix metalloproteinases