以血管生成细胞疗法为基础的血管增生和组织修复/再生已成为一种强有力的工具。然而，目前的细胞疗法方法主要依赖于祖细胞，其存在重大风险（如不受控制的分化、肿瘤发生和遗传/表观遗传异常）。此外，用于从诱导多能干细胞产生诱导内皮细胞（iECs）的重编程方法主要依赖于病毒载体，这也带来了额外的转化局限性。本研究描述了开发能够在不需要祖细胞和/或病毒载体的情况下推动基于重编程的血管生成疗法的人工外泌体（EVs）的过程。EVs源于原代人皮肤真皮成纤维细胞（HDFs），并经过工程改造以装载ETV2、FLI1和FOXC2（EFF）的转录因子基因/转录本。我们的结果表明，除EFF外，经过工程改造的EVs还负载有血管生成因子（如VEGF-A、VEGF-KDR和FGF2）的转录本。体外和体内研究表明，这种EVs有效地转染了HDFs，并在7-14天内驱动其向iECs直接转化。最后，在小鼠上的创伤愈合研究表明，经过工程改造的EVs导致创伤闭合和血管化改善。总之，我们的结果表明，经过工程改造的人类血管生成EVs具有推动体细胞向iECs直接重编程的潜力，并促进组织修复/再生。

Vasculogenic cell therapies have emerged as a powerful tool to increase vascularization and promote tissue repair/regeneration. Current approaches to cell therapies, however, rely mostly on progenitor cells, which pose significant risks (e.g., uncontrolled differentiation, tumorigenesis, and genetic/epigenetic abnormalities). Moreover, reprogramming methodologies used to generate induced endothelial cells (iECs) from induced pluripotent stem cells rely heavily on viral vectors, which pose additional translational limitations. This work describes the development of engineered human extracellular vesicles (EVs) capable of driving reprogramming-based vasculogenic therapies without the need for progenitor cells and/or viral vectors. The EVs were derived from primary human dermal fibroblasts (HDFs), and were engineered to pack transcription factor genes/transcripts of ETV2, FLI1, and FOXC2 (EFF). Our results indicate that in addition of EFF, the engineered EVs were also loaded with transcripts of angiogenic factors (e.g., VEGF-A, VEGF-KDR, FGF2). In vitro and in vivo studies indicate that such EVs effectively transfected HDFs and drove direct conversions towards iECs within 7-14 days. Finally, wound healing studies in mice indicate that engineered EVs lead to improved wound closure and vascularity. Altogether, our results show the potential of engineered human vasculogenic EVs to drive direct reprogramming processes of somatic cells towards iECs, and facilitate tissue repair/regeneration.