Exosomes: Biology, Sources and Isolation Techniques

Background Exosomes are nanosized extracellular vesicles of endosomal origin that mediate intercellular communication through the transfer of proteins, lipids, nucleic acids, metabolites, and other bioactive cargo. Their ability to regulate immune responses, tissue repair, angiogenesis, extracellular matrix remodeling, and cellular homeostasis has generated substantial interest in their diagnostic and therapeutic applications. Objectives To provide a comprehensive overview of exosome biology, molecular cargo, cellular sources, isolation and characterization methodologies, dermatologic applications, and emerging translational strategies relevant to regenerative medicine and dermatology. Methods A narrative review of contemporary literature was performed to summarize current evidence regarding exosome biogenesis, cargo sorting, cellular sources, isolation and characterization techniques, storage considerations, engineered therapeutic approaches, and clinical applications in dermatology. Results Exosomes are generated through the endosomal pathway and contain selectively packaged proteins, lipids, DNA, messenger RNAs, microRNAs, and other regulatory molecules that reflect the biological state of the parent cell. Mesenchymal stem cells, adipose‐derived stem cells, umbilical cord‐derived mesenchymal stem cells, platelets, fibroblasts, and keratinocytes have emerged as important exosome sources for regenerative applications. Advances in isolation technologies, including ultracentrifugation, size‐exclusion chromatography, immunoaffinity capture, and microfluidic platforms, have improved extracellular vesicle characterization and translational research. In dermatology, exosomes have demonstrated promising applications in wound healing, skin rejuvenation, hair regeneration, scar modulation, pigmentary disorders, inflammatory dermatoses, and cutaneous oncology. Furthermore, bioengineering approaches have enabled the development of exosome‐based drug delivery systems, targeted therapeutics, and hydrogel‐assisted delivery platforms. Conclusions Exosomes represent a rapidly evolving platform for precision diagnostics, regenerative medicine, and targeted therapeutics. Their unique biological properties, favorable safety profile, and cell‐free therapeutic potential position them as promising candidates for future dermatologic applications. However, challenges related to standardization, large‐scale manufacturing, characterization, regulatory approval, and long‐term safety must be addressed before routine clinical implementation can be achieved.