Comparing the Chondrogenic Potential in vivo of Autogeneic Mesenchymal Stem Cells Derived from Different Tissues

Objective: To compare the chondrogenic ability of mesenchymal stem cells (MSCs) derived from different tissues in rabbits' full-thickness articular cartilage defects. Methods: Sixty New Zealand white rabbits of ordinary grade with a body weight of 2.5 similar to 3.5kg were selected for this study. Six were sacrificed for preparation of deminerized bone matrix (DBM) as scaffold. Fifty-four were used for cartilage defects model. Full-thickness cartilage defect of knee joint was created on trochlear groove at two sides of the femur with a diameter of 4 mm and thickness of 3 mm. All 54 rabbits were randomly divided into 6 groups and treated by autogeneic MSCs isolated from bone marrow, periosteum, synovium, adipose tissue and muscle, respectively. The 6th group was a control group with nothing plugged into the defects. Every three rabbits were killed at three time points, which were 4, 8, and 12 weeks after the operation in each group. The reparative tissue samples were evaluated grossly, histologically, immunohistochemically, and graded according to gross and histological scales 12 weeks postoperatively. We input the scores into SPSS 11.5 software and the analysis of variance (one-way-ANOVA) and student-newman-keuls (SNK-q) test were used to process statistical analysis and find out if the differences between each group had statistical significance. Results: Fifty-four rabbits are included in the final analysis. The defects are all repaired by hyaline-like tissue except the control group. The bone-marrow-MSCs produced much more cartilage matrix than that of other groups. Gross and histological grading scale indicates that the defects repaired by MSCs isolated from bone marrow are superior to that repaired by MSCs isolated from periosteum, synovium, adipose tissue, and muscle (p < 0.05). In adipose-MSCs and muscle-MSCs group, some defects are even repaired by fibrous tissue. Conclusion: Bone-marrow-MSCs have greater in vivo chondrogenic potential than periosteum-, synovium-, adipose- and muscle-MSCs.