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.

中文翻译：

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探索纳米脂质体TGF-β1对组织工程血管移植物中诱导多能干细胞来源的血管平滑肌细胞的影响；体内研究

本研究探讨了脂质体转化生长因子 β1 (TGF-β1) 对动脉组织工程诱导多能干细胞 (iPSC) 衍生的血管平滑肌细胞 (VSMC) 表型转换的影响。我们提出了一种有效减少移植等待时间的创新方法。使用仿生灌注系统，从绵羊颈动脉开发生物支架来创建组织工程血管（TEV）。将源自兔 iPSC 的 VSMC 重新接种到这些 TEV 上以促进增殖。使用薄膜水合方法将TGF-β1封装在脂质体中以促进VSMC生长。通过酶联免疫吸附测定 (ELISA) 对这些脂质体中 TGF-β1 的受控释放进行定量。将纳米脂质体 TGF-β1 以 50 ng/mL 的浓度加载到支架中，并通过 ELISA 监测释放情况。使用CCK8试剂盒评估VSMC的增殖活性。采用实时 PCR、蛋白质印迹、免疫组织化学和流式细胞术等技术来评估 VSMC 表型转换。与对照组相比，脂质体 TGF-β1 处理导致 TEV 中的细胞增殖率增加 122.30%，表明没有细胞毒性。 ELISA 结果证实了脂质体 TGF-β1 的受控和持续释放。此外，我们通过将移植物植入兔主动脉并监测其性能四个星期，证明了脂质体 TGF-β1 在较长时间内持续递送的功效。我们的研究结果强调了纳米脂质体 TGF-β1 在诱导 TEV 内表型转化中的作用。这项研究强调了纳米脂质体 TGF-β1 在推进血管组织工程方面的巨大治疗潜力，为临床应用提供了新的途径，并满足了改善血管移植结果的迫切需求。总之，我们的研究展示了仿生环境和纳米脂质体 TGF-β1 对兔诱导多能干细胞衍生的 VSMC 的协同作用，强调 SMC 增殖的显着增加、TGF-β1 的控制释放、成功的移植物植入以及通过从绵羊颈动脉中开发 TEV，在动脉组织工程领域取得了开创性的成果。