Figure 8.

Schematic diagram of the study design. (a) SMSCs were isolated from the synovium obtained from human knee joints. (b) SMSCs were separated into the bFGF (−) and bFGF (+) groups. (c) For 3D pellet culture and transplantation, SMSCs harvested from passage 3 were aggregated by centrifugation. (d) In vitro, the pellets were cultured for 4 weeks in chondrogenic basal medium with BMP2 (50 ng/mL) and TGF-β3 (10 ng/mL), to induce chondrogenic differentiation. The histology of pellets, the expression of cartilage-differentiation-related genes, and ECM production were evaluated. (e) In vivo, osteochondral defects (the black dotted line in the left picture) were created in the femoral trochlea of scid mice. Synovial pellets from both groups were implanted into each knee (the black dotted line in the middle and right pictures), followed by histological evaluation (including cell tracing and scoring) 8 weeks after the operation. SMSCs, synovial mesenchymal stem cells; bFGF, basic fibroblast growth factor; 3D, three-dimensional; FBS, fetal bovine serum; DMEM, Dulbecco’s modified Eagle medium; FACS, fluorescence-activated cell sorting; BMP2, bone morphogenetic protein-2; TGF-β3, transforming growth factor-β3; ECM, extracellular matrix; sGAG, sulfated glycosaminoglycan; scid, severe combined immunodeficiency.