Updated project metadata. Extracellular vesicles (EVs), spherical nano-sized lipid-bilayer vesicular structure, is produced from host cells, and widely studied in microbiology, neurobiology, and bioengineering as drug delivery. Here, we report the new vaccine platform using a novel type of EVs, WW domain activated extracellular vesicles (WAEV). Our proteomics result showed that WAEV was activated by the WW domain independently, and distinct from the existing exosome.