Exosomes in tissue engineering and cell-free therapy: A comprehensive review

As a critical subclass of extracellular vesicles, exosomes have emerged as a research focus in tissue regeneration and precision therapy because of their unique molecular delivery and intercellular communication capabilities. This article systematically reviews the biogenesis, isolation, and characterization of exosomes and their role in advancing tissue engineering applications. Their multifaceted regulatory roles in bone/cartilage repair, neural regeneration, wound healing, and cardiovascular regeneration, including antiapoptotic, proangiogenic, immunomodulatory, and antifibrotic mechanisms, are highlighted. The innovations of this work lie in (1) the comprehensive analysis of engineered exosome strategies—such as surface modification, cargo-loading optimization, and synergistic integration with biomaterials—to overcome the limitations of traditional delivery systems; (2) the proposal of the dual regulatory potential of exosomesin cancer immunotherapy and autoimmune diseases, offering novel insights for clinical translation; and (3) the envisioning of future directions by integrating artificial intelligence (AI) and three-dimensional (3D) bioprinting to advance scalable production and precision design of exosome-based therapies. This article further addresses current challenges (e.g., heterogeneity, standardization, and safety) and emphasizes interdisciplinary collaboration to bridge the gap between fundamental research and clinical translation. This review provides a theoretical framework and technical foresight for advancing regenerative medicine and precision therapeutics.