Six patients undergoing plastic surgery procedures for the removal of adipose tissue from which waste material (adipose tissue) will be taken to obtain MSCs for EVs production. Five patients undergoing hip or knee joint replacement surgery from which waste material (osteo-cartilaginous material) will be taken to obtain chondrocytes for functional tests. Forty patients undergoing regenerative medicine treatments with PRP from which a waste aliquot (obtained during PRP preparation) will be taken to obtain plasma for fibrin gel production.

To implement the preliminary data obtained by the PI in the development of a protocol to achieve efficient incorporation of mesenchymal stem cell-derived extracellular vesicles into platelet-rich plasma-derived fibrin gels and characterize their release. MSC-EVs will be embedded in fibrin gel using PRP provided by patients enrolled in the study that is activated to obtain the solid form. To monitor the incorporation and release of EVs from the PRP-gel, EVs will be labeled with a fluorescent marker to allow their subsequent detection by cytometry or imaging methods. The ability of the released EVs to be incorporated into human chondrocytes and penetrate cartilage will be tested using three in vitro models: i) flow cytometry in a 2D culture model; ii) a 3D microfluidic model; iii) a Quantitative Imaging with cartilage explants. Biological activity will be tested on pathological chondrocytes.