Targeting Tetraspanins at Cell Interfaces: Functional Modulation and Exosome‐Based Drug Delivery for Precise Disease Treatment

Tetraspanins are key players in various physiological and pathological processes, including malignancy, immune response, fertilization, and infectious disease. Affinity ligands targeting the interactions between tetraspanins and partner proteins are promising for modulating downstream signaling pathways, thus emerging as attractive candidates for interfering related biological functions. Due to the involvement in vesicle biogenesis and cargo trafficking, tetraspanins are also regarded as exosome markers, and become molecular targets for drug loading and delivery. Given the rapid development in these areas, this minireview focuses on recent advances in design and engineering of affinity binders toward tetraspanins including CD63, CD81, and CD9. Their mechanism of actions in modulating protein interactions at cell interfaces and treatment of malignant diseases are discussed. Strategies for constructing exosome-based drug delivery platforms are also reviewed, with emphasis on the important roles of tetraspanins and the affinity ligands. Finally, challenges and future development of tetraspanin-targeting therapy and exosomal drug delivery platforms are also discussed.