The size data was recorded at the 173° scattering angle and 25° C. NP0 and NP5000 sizes are reported based on the number distribution (PDI: 0.02 and 0. Cartilage explants were extracted from femoral and tibial condyle cartilage of 3-5-month-old pigs using biopsy punchers (d=4 mm) while excluding subchondral bone. Explants were washed three times with supplemented PBS and allowed to equilibrate overnight in DMEM supplemented with 25 mM HEPES under regular cell culture conditions (37•C, 5% CO2, 95% relative humidity).