Immune response regulation by transduced mesenchymal stem cells with decorin gene on bleomycin-induced lung injury, fibrosis, and inflammation

Background: Pulmonary fibrosis is a pathological hallmark of lung injury. It is an aggressive disease that replaces normal lung parenchyma by fibrotic tissue. The transforming growth factor-beta–mothers against decapentaplegic homolog 3 (TGF-β1–Smad3) signaling pathway plays a key role in regulating lung fibrosis. Decorin (DCN), a small leucine-rich proteoglycan, has a modulatory effect on the immune system by reversibly binding with TGF-β and reducing its bioavailability. Mesenchymal stem cell (MSC) therapy is a new strategy that has an immune-modulatory capacity. Objective: The aim of this study was to introduce a new therapeutic approach to harness remodeling in injured lung. Material and Methods: Bone marrow MSCs were isolated and transduced by decorin gene. Lung injury was induced by bleomycin and mice were treated with MSCs, MSCs–decorin, and decorin. Then, oxidative stress biomarkers, remodeling biomarkers, bronchoalveolar lavage cells, and histopathology study were conducted. Results: Reduced catalase and superoxide dismutase increased due to treatments. Elevated malondialdehyde, hydroxyproline, TGF-β levels, and polymorphonuclear cells count decreased in the treated groups. Additionally, the histopathology of lung tissues showed controlled inflammation and fibrosis. Conclusion: Transfected decorin gene to MSCs and used cell therapy could control remodeling and bleomycin-induced lung injury.