MAIN METHODS: Human bone marrow derived MSCs were isolated, expanded in vitro and transfected with adiponectin gene containing plasmid vector. Total RNA was extracted and cDNA was prepared by reverse transcription polymerase chain reaction (RT-PCR). The expression of adiponectin gene and protein in GM-MSCs was analyzed by PCR and Western blotting respectively. The secretion of adiponectin protein from GM-MSCs was analyzed by enzyme-linked immunosorbent assay.
KEY FINDINGS: The expression of adiponectin gene and plasmid DNA was detected in GM-MSCs but not in control group of MSCs. Adiponectin gene expression was detected in GM-MSCs at 2, 7, 14, 21 and 28days after transfection. Western blotting analysis revealed the expression of adiponectin protein only in GM-MSCs. The GM-MSCs stably secreted adiponectin protein into culture media at least for 4weeks.
SIGNIFICANCE: GM-MSCs express and secret adiponectin protein. Therefore, these adiponectin secreting GM-MSCs could be instrumental for the supplementation of adiponectin in the treatment of adiponectin deficiency related diseases.
METHODS: Medial femoral condyle defect was created in both knees of twenty-four mature New Zealand white rabbits, and the animals were divided into four groups containing six animals each. After 3 weeks, the right knees were transplanted with PVA-chitosan-MSC, PVA-chitosan scaffold alone, alginate-MSC construct or alginate alone. The left knee was kept as untreated control. Animals were killed at the end of 6 months after transplantation, and the cartilage repair was assessed through Brittberg morphological score, histological grading by O'Driscoll score and quantitative glycosaminoglycan analysis.
RESULTS: Morphological and histological analyses showed significant (p < 0.05) tissue repair when treated with PVA-chitosan-MSC or alginate MSC as compared to the scaffold only and untreated control. In addition, safranin O staining and the glycosaminoglycan (GAG) content were significantly higher (p < 0.05) in MSC treatment groups than in scaffold-only or untreated control group. No significant difference was observed between the PVA-chitosan-MSC- and alginate-MSC-treated groups.
CONCLUSION: PVA-chitosan hydrogel seeded with mesenchymal stem cells provides comparable treatment outcomes to that of previously established alginate-MSC construct implantation. This study supports the potential use of PVA-chitosan hydrogel seeded with MSCs for clinical use in cartilage repair such as traumatic injuries.