Bone marrow mesenchymal stem cells combined with acellular dermal matrix repair beagle dog articular cartilage defects / 中国组织工程研究

ABSTRACT

BACKGROUND: Dermis-derived extracellular matrix, as a cartilage repair scaffold, provides a space for the growth of cartilage tissue, and promotes cell adhesion and proliferation. Bone marrow mesenchymal stem cells have the potential to differentiate into chondrocytes. Both of them used alone have disadvantages. OBJECTIVE: To evaluate the feasibility of bone marrow mesenchymal stem cells combined with calf acellular dermal matrix to repair beagle dog articular cartilage defects. METHODS: Beagle dog bone marrow blood was extracted from Beagle dogs. Bone marrow mesenchymal stem cells were obtained by density gradient centrifugation and passaged. Acellular dermal matrix was prepared from the dorsal dermis of neonatal calves by ultrasonic oscillation, freeze-drying and pepsin. 0. 2 mL of cell suspension was added to the surface of acellular dermal matrix until covered, then which was placed in a 5% CO2 incubator at 37 °C for 48 hours. Twelve adult beagle dogs were used to establish knee joint cartilage defect models, and then randomized into three groups In the acellular dermal matrix combined with bone marrow mesenchymal stem cells group (combination group), cartilage defects were repaired with acellular dermal matrix combined with bone marrow mesenchymal stem cells. In the single acellular dermal matrix group, cartilage defects were repaired with acellular dermal matrix. The model control group received no treatment. At 12 weeks after surgery, the right knee joints were observed by stereomicroscope, hematoxylin-eosin staining and type II collagen immunohistochemical staining. RESULTS AND CONCLUSION: (1) Scanning electron microscopy showed that bone marrow mesenchymal stem cells adhered to and grew well in the acellular dermal matrix. (2) Hematoxylin-eosin staining revealed that the repaired surface in the combination group was slightly lower than that of the surrounding normal tissues, and the repaired tissues integrated well with the surrounding cartilages. The defects in the single acellular dermal matrix group were filled with fibrous tissues. Few surrounding tissues of defect were repaired in the model control group. (3) Type II collagen immunohistochemical staining showed that in the combination group, articular cartilage defects were filled with chondrocyte-like tissues. In the single acellular dermal matrix group, the defect was filled with fibrous tissues. No tissue was found in the model control group. (4) These results indicate that the new calf acellular dermal matrix has good biocompatibility and can promote the proliferation of bone marrow mesenchymal stem cells. Autologous bone marrow mesenchymal stem cells combined with acellular dermal matrix can effectively repair beagle dog knee joint cartilage defects.