Exploring the effects of Nano-liposomal TGF-β1 on induced pluripotent stem Cell-Derived vascular smooth muscle cells in Tissue-Engineered vascular graft; an in vivo study

Abstract

This study explores the impact of liposomal Transforming Growth Factor β1 (TGF-β1) on phenotypic switching in Vascular Smooth Muscle Cells (VSMCs) derived from induced pluripotent stem cells (iPSCs) for arterial tissue engineering. We present an innovative approach to reducing graft waiting periods effectively. Using a biomimetic perfusion system, biological scaffolds were developed from sheep's carotid artery to create Tissue-Engineered Vessels (TEVs). VSMCs derived from rabbit iPSCs were reseeded onto these TEVs to promote proliferation. TGF-β1 was encapsulated in liposomes using the thin-film hydration method to enhance VSMC growth. The controlled release of TGF-β1 from these liposomes was quantified through enzyme-linked immunosorbent assay (ELISA). Nano-liposomal TGF-β1 was loaded into the scaffolds at a concentration of 50 ng/mL, with the release monitored through ELISA. The proliferative activity of VSMCs was evaluated using the CCK8 kit. Techniques such as real-time PCR, Western blot, Immunohistochemistry, and Flowcytometry were employed to assess VSMC phenotypic switching. Liposomal TGF-β1 treatment led to a 122.30 % increase in cell proliferation rate in TEVs compared to the control group, indicating no cytotoxicity. ELISA results confirmed a controlled and sustained release of liposomal TGF-β1. Furthermore, we demonstrated the efficacy of liposomal TGF-β1 for sustained delivery over an extended period by implanting the grafts in rabbit aortas and monitoring their performance for four weeks. Our findings highlight the role of Nano-liposomal TGF-β1 in inducing phenotypic transformation within TEVs. This research underscores the promising therapeutic potential of Nano-liposomal TGF-β1 in advancing blood vessel tissue engineering, offering novel pathways for clinical application and addressing the critical need for improved vascular graft outcomes. In conclusion, our study showcases the synergy between a biomimetic environment and Nano-liposomal TGF-β1 on rabbit induced pluripotent stem cell-derived VSMCs, emphasizing the significant increase in SMC proliferation, controlled release of TGF-β1, successful graft implantation, and the pioneering approach in arterial tissue engineering through the development of TEVs from sheep carotid arteries.