EVs from various sources without modification for OA therapy. Abbreviation: BMSCs, Bone marrow mesenchymal stem cells; ADSCs, adipose mesenchymal stem cells; SMSCs, synovial mesenchymal stem cells; EMSCs, embryonic mesenchymal stem cells; UMSCs, umbilical cord mesenchymal stem cells; AMSCs, amniotic mesenchymal stromal cells; AFSCs, amniotic fluid stem cells; SHED, stem cells from human exfoliated deciduous teeth; CPCs, chondrogenic progenitor cells; SFB, synovial fibroblasts; hypACT, hyperacute serum; PRP, platelet-rich plasma; SECMs, sea cucumber extracellular matrices; ASCs, antler stem cells.