Engineered exosome-based treatment for peripheral nerve regeneration: a narrative review of clinical prospects

With their unique therapeutic properties and amenability to engineering modifications, exosomes are considered a promising tool for treating peripheral nerve injuries. Through genetic engineering or physicochemical modifications, the targeting ability and functionality of exosomes can be further enhanced, enabling efficient delivery of therapeutic molecules and significantly boosting their therapeutic potential. This review aims to explore exosome-based therapies in peripheral nerve repair and their mechanisms and summarizes recent advances in the roles of exosomes in neuroprotection, axonal regeneration, vascular regeneration, and inflammatory modulation. Exosomes act as natural messengers between cells, carrying genetic materials, cytokines, and growth factors that can modulate the local microenvironment and foster peripheral nerve regeneration. Studies have shown that exosomes derived from Schwann cells, macrophages, neurons, and mesenchymal stem cells can all promote axonal regeneration and modulate inflammatory responses through various mechanisms. Compared with cell therapy, exosome therapy offers greater stability and safety, with the ability to traverse biological barriers, presenting new possibilities for regenerative medicine and precision therapy. However, challenges such as the heterogeneity and complexity of exosomes, uncertainty of in vivo distribution and metabolic pathways, and the limitations of targeting remain to be addressed. Future research will focus on the engineering modifications of exosomes to enhance their therapeutic efficiency and targeting precision.