Transplantation of Cultured Allogenic Chondrocyte-Collagen Gel Composite into the Articular Cartilage Defect of Rats / 대한정형외과연구학회지

ABSTRACT

As one of many cell-many cell-based cartilage repairing methods, transplantation of chondrocyte-embedded-collagen gels in cartilage defect was performed for more satisfactory regeneration of cartilage. The authors performed this study to investigate whether the TGF-beta1 treatment of chondrocytes can do some additional synergistic effect on the transplantation of chondrocyte-embedded-collagen gels for crtilage repair. Chondrocytes were isolated from the articular cartilage of newborn Sprague-Dawley rats. Chondrocytes cultured for 10 days in monolayer were embedded in the 0.45% type I collagen gel. Full-thickness cartilage defect was made in the patellar groove of adult Sprague-Dawley rats. Chondrocytes culdefect was made in the patellar groove of adult Sprague-Dawley rats. The cartilage defects were treated with the following methods in a total of 200 animals, which were assigned to 5 different groups of 40 rats. In the control group, the deffect was left without any treatment, in group I, the defect was filled with collagen gel only, in group II, with collagen gel coontaining 10 ng/ml concentration of TGF-beta1, in group III, with collagen gel containing chondrocytes, and in group IV, with collagen gel containing chondrocytes and TGF-beta1. At 1, 2, 4, 8, 12 weeks after the operation, eight rats of each group were sacrificed, and their distal femurs were harvested for the histologic and biomechanical tests. The section s were stained with hematoxilin and eosin. Alcian-blue, and Safranin-O. Regenerated cartilage was analyzed by the semiquantitative histological grading system. Point indentation test was performed as a biomechanical evaluation, and the stiffness was calculated. The results of the histological grading system revealed that the scores gradually increased with time in all groups, and the scores of group III and IV were higher than those of control, group I and II. The biomechanical study showed that the stiffness gradually increased to reach a plateau level in each group. In control, group I and II, the stiffness increased up to the eighth week and remained around the increased level at the twelfth week, and did not show any statistically significant difference between the groups. In group III and IV, the stiffness was higher than in control group, and increased markedly at the fourth week and the increased level was maintained onwards. The results of this study showed that the transplantation of chondrocyte-embedded-collagen gels enhanced the healing process, and the treatment of TGF-beta1 demonstrated at least partially significant improvement.