Localized Administration of Bcar3 siRNA via Nano-Self-Assembly to Treat Idiopathic Pulmonary Fibrosis by Disrupting Macrophage-Fibroblast Crosstalk

Abstract

Chenxi Zeng,1,* Qi Wang,2,* Xuhan Liu,3,* Kai Wang,1 Congjian Wang,1 Xuetao Ju,1 Tianlai Wang,1 Qing Zhou,4 Xiangning Fu,1 Jun Yu,1 Yi Wang4 1Department of Thoracic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People’s Republic of China; 2Department of Geriatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People’s Republic of China; 3Department of Emergency Medicine, Shenzhen University General Hospital, Shenzhen University Clinical Medical Academy, Shenzhen University, Shenzhen, Guangdong Province, People’s Republic of China; 4Department of Pulmonary and Critical Care Medicine, NHC Key Laboratory of Respiratory Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yi Wang, Department of Pulmonary and Critical Care Medicine, NHC Key Laboratory of Respiratory Diseases, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, 430030, People’s Republic of China, Email [email protected] Jun Yu, Department of Thoracic Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, 430030, People’s Republic of China, Email [email protected]: Idiopathic pulmonary fibrosis (IPF) is a severe interstitial lung disease characterized by chronic lung injury leading to macrophage infiltration and fibroblast activation. However, there is no effective therapeutic strategy targeting the crucial crosstalk between macrophages and fibroblasts to halt IPF progression.Methods: Studies were conducted in IPF patients and fibrotic mice models to elucidate the role of Bcar3 in the pathogenesis of pulmonary fibrosis. The effect of Bcar3 on macrophage polarization, fibroblast activation, and related signaling pathways were next investigated to unravel the underlying mechanisms.Results: Our study elucidates a marked increase in Bcar3 expression in lung tissues from IPF patients and fibrotic mice, recording 1.7 and 7.8-fold increases compared to control subjects, respectively. Additionally, Bcar3 was found to significantly enhance macrophage activation and fibroblast differentiation, observable in both in vivo and in vitro settings. Mechanistically, the upregulation of Bcar3 in macrophages was reliant on Stat6, while in fibroblasts, it depended on TGFβR1/Smad3. Furthermore, Bcar3 augmented IL-4/Stat6 pathway in macrophages and TGF-β/Smad3 pathway in fibroblasts, supporting a synergistic activation loop that expedited lung fibrogenesis. Notably, intratracheal injection of liposomes containing Bcar3 siRNA precisely delivered gene therapeutics to lung macrophages and fibroblasts, effectively reducing Bcar3 expression to 59% of baseline levels. Importantly, this intervention protected mice from lung fibrosis induced by either FITC or bleomycin, as well as human precision-cut lung slices against TGF-β 1 stimulation.Conclusion: Our study underscores the pivotal role of Bcar3 in orchestrating the macrophage-fibroblast crosstalk during pulmonary fibrosis progression. Targeting Bcar3 emerges as a novel therapeutic avenue to halt IPF progression and enhance patient prognosis.Keywords: idiopathic pulmonary fibrosis, Bcar3, liposomes, macrophages, fibroblasts

Keywords

• idiopathic pulmonary fibrosis
• bcar3
• liposomes
• macrophages
• fibroblasts