The repairing effect of articular cartilage by cellular spheroids composed ofsynovial cells and chondrocytes

自体软骨细胞移植（ACT）已被选为治疗骨关节炎。然而，该技术需要来自健康软骨的关节软骨细胞（AC），这与供体部位的发病率相关。由于来自老年患者的AC在体外显示有限的增殖，ACT未被广泛接受用于治疗骨关节炎病变。另一方面，其高增殖能力不随年龄变化的滑膜衍生细胞（SY）一直关注具有向软骨细胞分化能力的间充质干细胞的定位。采用二步酶消化法从日本白色家兔4只膝关节分离AC和SY，进行原代培养，比较细胞的传代生长率。将AC和SY在非粘附培养板中高密度悬浮培养，收集细胞球体，用甲苯胺蓝、番红O、1型和2型胶原免疫组织化学方法进行组织学观察，并用逆转录-聚合酶链反应（RT-PCR）检测与软骨细胞特异性分化相关的基因表达。结果表明，无论细胞组分的比例如何，我们都成功地使用AC和SY的混合物在短时间内制备了大量的细胞球体。SY有望在ACT中有效替代AC。

Autologous Chondrocyte Transplantation(ACT) has been chosen as the treatment for Osteoarthritis. However, this technique needs the articular chondrocytes(AC) from healthy cartilage, which associates donor site morbidity. As AC from aged patents show limited proliferation in vitro, ACT is not accepted widely for treatment of ostearthritic lesions. On the other hand, the synovium derived cells(SY) whose high proliferation potency does not changed regardless of age have been focusing the localization mesenchymal stem cells of differentiation potency into chondrocytes. AC and SY from 4 knee of a Japanese white rabbit were isolated with 2 step enzymatic digestion and cultured, the passage growth rate of the cells were compared. When AC and SY cultured it in a high density suspension state in non-adhesive culture plate, cellular spheroids were collected and then histological evaluated was conducted with toluidine blue, safranin O and immunohistochemistry of collagen type 1 and 2.The gene expressions concerning choncrocyte-specific differentiation were also tested by Reverse Transcriptase-Polymerase Chain Reaction. In results, we successfully prepared a large quantity of cellular spheroids in a short period using mixed AC and SY regardless of cellular component rates. Effective usage of SY is expected as a replacement of AC in ACT.