Novel balloon catheter containing therapeutic mRNA with smart RNA switch alleviate restenosis after vascular injury

Abstract Background Cardiovascular diseases are the leading cause of death worldwide, and vascular intervention is an effective method for ischemic heart diseases. However, vascular restenosis significantly affects the long-term therapeutic outcomes, which mainly caused by excessive proliferation of vascular smooth muscle cells (VSMCs). While drug-eluting stents and drug-coated balloons have successfully decreased the incidence of restenosis by inhibiting the VSMCs proliferation, they concurrently suppress the repair of endothelial cells (ECs) and re-endothelialization, thereby increasing the risk of late thrombotic events and mortality. Consequently, it is urged to develop novel high-selectively therapeutic devices to overcome vascular restenosis. In current mRNA therapies of cardiovascular diseases, there are few effective systems for cell-specific expression. Therefore, we propose to utilize RNA editing (based on ADAR1 RNA editing) to investigate a smart RNA molecular switch capable of cell-specific recognition and selectively releasing payload in targeted cells or tissues for cell precision therapy. However, the application of gene editing in the cardiovascular system faces challenge of low delivery efficiency. We innovatively take the balloon as a specific and efficient tool to delivery therapeutic mRNA, which may be a potential therapy for vascular restenosis. Objective We investigated therapeutic mRNA containing a smart RNA switch to selectively suppress the VSMCs proliferation while promoting re-endothelialization and delivered by balloon as a novel therapy in vascular restenosis animal models. Results For RNA switch high-throughput screening, we utilized PiggyBac transposon system to establish monoclonal overexpressing cell lines and chose the cell strain with expression levels closely mimicking VSMCs and ECs. We found the most effective RNA switch from dozens of potential candidates which could specifically recognize VSMCs but not ECs. Therapeutic mRNA sequences containing the RNA switch efficiently initiated payload translation in VSMCs while maintaining payload silence in primary vascular endothelial cells, which effectively and selectively inhibited VSMCs excessive proliferation and promoted endothelial repair. Additionally, we developed an interventional balloon delivery system for mRNA drugs, achieving in situ delivery to cardiovascular lesions in vivo, demonstrating therapeutic effects consistent with cellular phenotypes in animal models. Conclusion We suggest that the smart RNA switch can serve as a novel, cell-specific therapeutic tool for restenosis and other cardiovascular diseases. Additionally, utilizing a balloon for mRNA delivery represents a new paradigm for mRNA therapy and gene editing in the cardiovascular field.