Collagen Type Ⅱ Hydrogel-Encapsulated Bone Marrow-derived MSCs versus Bone Marrow Nucleated Cells in the Chondral Defect Treatment

摘要

Although experiments have confirmed that mesenchymal stem cells (MSCs) are the most promising seed cells in the treatment for cartilage defects, the separation and purification of MSCs remain complex and uncertain. Bone marrow nucleated cells may be another option. But whether it is effective enough to substitute MSCs? In this study, twenty Guizhou minipigs were used to create full-thickness chondral defects of 6.0 mm in diameter in the knee joints, and divided between two time points (4 and 8 weeks) for final assessment. At every time point, animals were separated into four groups: the CON group underwent no implantation; the collagen type Ⅱ hydrogel group (COL); the collagen type Ⅱ hydrogel + bone marrow-derived MSCs group (BMSCs); the collagen type Ⅱ hydrogel + bone marrow nucleated cells group (BNCs). The samples were grossly examined, observed through a stereo microscope, histologically analyzed and evaluated with O'Driscoll score respectively. The cartilage repair of the two cell-treated groups was improved markedly than the CON and the COL group, while the repair tissues of the two cell-treated groups showed no significant difference 8 weeks after surgeries. These data indicate that bone marrow nucleated cells contribute to the repair of cartilage with collagen type Ⅱ hydrogel as scaffolds, which have comparable results with bone marrow-derived MSCs. And the transplantation of autologous bone marrow nucleated cells as seed cells may be a more economic and convenient technique for cartilage repair in clinic application.