Bone marrow mesenchymal stem cells combined with peptide hydrogel and chondrogenic factors for repair of articular cartilage defects in rabbits / 中国组织工程研究

ABSTRACT

BACKGROUND:Peptide hydrogel has good plasticity, and it can fil the injured site very wel; therefore, to use this material as a scaffold is a feasible exploration in bone and cartilage tissue engineering. OBJECTIVE:To test the effect of bone marrow mesenchymal stem cels combined with injectable peptide hydrogel and chondrogenic factors for repair of articular cartilage defects in rabbits. METHODS:Bone marrow mesenchymal stem cels from rabbits were isolated and cultured. A ful-thickness bone-cartilage defect model, 5 mm in diameter and 3 mm in depth, was made on the left knee joint of rabbits, and the right knee joint of rabbits with no treatment was used as control after modeling. There were three experimental groups: self-assembling peptide hydrogel group, peptide hydrogel+chondrogenic factors group, and peptide hydrogel+chondrogenic factors+bone marrow mesenchymal stem cels group. Transforming growth factor β1, dexamethasone and insulin-like growth factor 1 were mixed as chondrogenic factors and added into self-assembling peptide hydrogel or bone marrow mesenchymal stem cels. Twelve weeks after treatment, animals were sacrificed for gross and histological observation, X-ray radiography, and histological evaluation using immunohistochemistry method. RESULTS AND CONCLUSION:At 12 weeks after treatment, the self-assembling peptide hydrogel group showed excelent results in the cartilage repair, and better achievements in safranin-O staining, colagen II immunostaining, and histological scores than the other groups (P < 0.05); the peptide hydrogel+chondrogenic factors group had better repair effects similar to the self-assembling peptide hydrogel group, but the expression of proteoglycans was higher than that in the control group (P < 0.01); there were poorer repair effects and more osteophytes in the peptide hydrogel+chondrogenic factors+bone marrow mesenchymal stem cels group than the the peptide hydrogel+ chondrogenic factors group. Experimental findings indicate that the self-assembling peptide hydrogel can repair cartilage defectsin situ and improve cartilage repair, which is expected to improve current repairing effects on cartilage defects.