Plant-derived exosomes: Structure, isolation, biological functions, and therapeutic potentials

Exosomes are small extracellular vesicles that play a role in intercellular communication by transporting bioactive lipids, proteins, and nucleic acids. While animal- derived exosomes have been extensively studied, plant-derived exosomes (PDEs) have emerged as a promising alternative in various fields, such as cancer therapy, immunomodulation, drug delivery, diagnostic biomarker development and tissue regeneration due to their bioavailability, sustainability, and high efficiency in modulating cellular communication. This review provides a comprehensive overview of the current state of knowledge regarding PDEs, despite their limited use in therapy and analysis. The structure, functional roles, therapeutic potential of PDEs are discussed, and current isolation and characterization methods, such as ultracentrifugation, size-exclusion chromatography, and exosome loading techniques are critically evaluated, highlighting challenges in standardization and yield optimization. Finally, current clinical challenges, translational limitations, and future perspectives for the application of PDEs are concluded, emphasizing the need for standardized protocols and rigorous preclinical evaluation to fully harness their therapeutic potential.