Metabolites, chemotherapeutic agents, cytokines, igonucleotides, metabolites, chemotherapeutic agents, cytokines, and immune modula- and immune modulators, target by engineered ERK1 Activator supplier exosomes [16]. In OA related study, tors, may be delivered to acan be delivered to a target by engineered exosomes [16]. In OA associated investigation, exosomes inside the joint, origins tissue-specific mesenchymal stem exosomes from several origins from multiplesuch as within the joint, such as tissue-specific mesenchymal cells (MSCs), stem cells (MSCs), chondrocytes, synovial fibroblasts (SFBs), osteoblasts, tenocytes, IPFP chondrocytes, synovial fibroblasts (SFBs), osteoblasts, tenocytes, IPFP adiadipocytes, and platelet-rich plasma (PRP), and been with OA progrespocytes, and platelet-rich plasma (PRP), happen to be detected havechangedetected and modify with OA progression [179] (Figure 1). Herein we go over the biosynthesis, origins, and sion [179] (Figure 1). Herein we talk about the biosynthesis, origins, and contents of exo- contents of exosomes, roles in OA pathogenesis, progression, and treatment. somes, and evaluation their and evaluation their roles in OA pathogenesis, progression, and treatment.Figure 1. Tissue sources Tissue sources of exosomes inExosomes joint. Exosomesmultiple kinds ofmultiple sorts Figure 1. of exosomes inside the knee joint. the knee are secreted by are secreted by cells of the joint, which includes adipocytes, adipose-derived stem cells (ADSCs), synovium-derived mesof cells of your joint, like adipocytes, adipose-derived stem cells (ADSCs), synovium-derived enchymal stem cells (MSCs), synovial fibroblasts and macrophages, chondrocytes, osteoblasts and mesenchymal stem cells (MSCs), synovial fibroblasts and macrophages, chondrocytes, osteoblasts and osteocytes in the subchondral bone, vascular endothelial cells, immune cells like T cells, B cells, osteocytes meniscus cells, periodontal ligament cells, tenocytes, tendon stem cells, and dendritic cells (DCs) in the subchondral bone, vascular endothelial cells, immune cells such as T cells, B cells, and dendritic cells These exosomes are periodontal ligament cells, tenocytes, tendon and bone marrow-derived MSCs.(DCs) meniscus cells, involved within the regulation of joint homeosta- stem cells, and bone marrow-derived initiation and progression of OA. sis, cell ell communications, plus the MSCs. These exosomes are involved inside the regulation of joint homeostasis, cell ell communications, as well as the initiation and progression of OA.neering 2022, 9, x FOR PEER Review Bioengineering 2022, 9,3 of3 of2. Formation and Origin ofand Origin of Exosomes two. Formation Exosomes The concept of `exosomes’ was first proposed in 1981 by Trams et al. [20].Trams etthe [20]. In 1983, The idea of `exosomes’ was initial proposed in 1981 by In 1983, al. currently definedcurrently defined initial identified in sheep reticulocytes and named by the exosomes have been exosomes have been initial identified in sheep reticulocytes and named by Johnstone et al. [21]. Nonetheless, theHowever, theclinical applications have been limited by the Johnstone et al. [21]. widespread widespread clinical applications had been limited by the low yield for low yield for the system used and unexpected therapeutic effects [22]. Be- [22]. In addition to, the D2 Receptor Inhibitor web production production method utilized and unexpected therapeutic effects sides, the function of exosomes is dependent on both on each the type and situation from the cells that the function of exosomes is dependent the sort and situation on the cel.