A role for MCP-1/CCR2 in interstitial lung disease in children

<p>Abstract</p> <p>Background</p> <p>Interstitial lung diseases (ILD) are chronic inflammatory disorders leading to pulmonary fibrosis. Monocyte chemotactic protein 1 (MCP-1) promotes collagen synthesis and deletion of the MCP-1 receptor CCR2 protects from pulmonary fibrosis in ILD mouse models. We hypothesized that pulmonary MCP-1 and CCR2⁺T cells accumulate in pediatric ILD and are related to disease severity.</p> <p>Methods</p> <p>Bronchoalveolar lavage fluid was obtained from 25 children with ILD and 10 healthy children. Levels of pulmonary MCP-1 and Th1/Th2-associated cytokines were quantified at the protein and the mRNA levels. Pulmonary CCR2⁺, CCR4⁺, CCR3⁺, CCR5⁺and CXCR3⁺T cells were quantified by flow-cytometry.</p> <p>Results</p> <p>CCR2⁺T cells and MCP-1 levels were significantly elevated in children with ILD and correlated with forced vital capacity, total lung capacity and ILD disease severity scores. Children with lung fibrosis had significantly higher MCP-1 levels and CCR2⁺T cells in bronchoalveolar lavage fluid compared to non-fibrotic children.</p> <p>Conclusion</p> <p>The results indicate that pulmonary CCR2⁺T cells and MCP-1 contribute to the pathogenesis of pediatric ILD and might provide a novel target for therapeutic strategies.</p