Clinical significance of MCP-1 levels in BALF and serum in patients with interstitial lung diseases

It has previously been reported that the expression of monocyte chemoattractant protein-1 (MCP-1) in the lung tissues of patients with idiopathic pulmonary fibrosis (IPF) was different from that in the tissues of patients with other interstitial lung diseases (ILDs). The aim of this study was to determine whether this difference reflects the amount of MCP-1 in the bronchoalveolar lavage fluid (BALF) or serum of patients with ILD, and whether such a correlation, if it exists, is clinically useful. MCP-1 concentrations in the BALF and sera were evaluated in 86 patients with ILDs including IPF, acute interstitial pneumonia, interstitial pneumonia with collagen vascular disease (IP-CVD), chronic interstitial pneumonia (CIP), bronchiolitis obliterans-organizing pneumonia, sarcoidosis, hypersensitivity pneumonitis, and in 10 normal healthy volunteers who were controls (NC). BALF MCP-1 levels were significantly elevated in the IPF, IP-CVD, CIP and sarcoidosis groups compared with the NC group. The level in the IPF group was significantly higher than that in any other patient group. Serum MCP-1 levels in the IPF, IP-CVD, CIP and sarcoidosis groups were significantly higher than the NC group. No statistical difference was found in serum MCP-1 levels between the IPF, IP-CVD and CIP groups. BALF MCP-1 levels were significantly higher than serum MCP-1 levels in the IPF group and lower than in the IP-CVD and CIP groups. Serum MCP-1 levels correlated with the clinical course of ILD treated with corticosteroid therapy. These results show that measurement of monocyte chemoattractant protein-1 levels in both bronchoalveolar lavage fluid and serum may be helpful in discriminating idiopathic pulmonary fibrosis from other types of interstitial lung disease and that monitoring of serum monocyte chemoattractant protein-1 may be useful for predicting the clinical course of interstitial lung diseases.