Scleraxis lentivirus-transfected human amniotic mesenchymal stem cells promote tendon-bone healing in Rabbits / 中国组织工程研究

ABSTRACT

BACKGROUND: Human amniotic mesenchymal stem cells have a wide variety of sources, low immunogenicity, and multilineage differentiation potential. Studies have confirmed that Scleraxis gene can induce human amniotic mesenchymal stem cells to differentiate into ligaments and accelerate tendon-bone healing. OBJECTIVE: To explore whether Scleraxis induces human amniotic mesenchymal stem cells to promote tendon-bone healing in vivo in rabbits, providing new options for clinical treatment of tendon-bone healing. METHODS: The study protocol was approved by the Ethic Committee of the Affiliated Hospital of Zunyi Medical University, and written informed consent was obtained from each puerpera. The healthy full-term maternal placenta was taken and cultured, and human amniotic mesenchymal stem cells were isolated and cultured by trypsin digestion twice. Then the morphology of the cells was observed under an inverted microscope, and the cells were further cultured until the third generation for subsequent experiments. The lentivirus carrying the Scleraxis gene was transfected into human amniotic mesenchymal stem cells in vitro. Expression levels of ligament-related genes were detected by real-time fluorescent quantitative PCR, and the expression levels of related proteins were detected by immunofluorescence. Human amniotic mesenchymal stem cells transfected with Scleraxis gene were injected into the extraarticular tendon-bone model of rats. After 3 months, specimens were taken to observe the tendon-bone healing. RESULTS AND CONCLUSION: (1) Human amniotic mesenchymal stem cells from passage to third generation showed long fusiform and vortex-like adherent growth under the inverted phase contrast microscope. (2) The third-generation human amniotic mesenchymal stem cells expressed green fluorescence after 24 hours of infection with the Scleraxis gene lentivirus, and the fluorescence expression was strong and stable. (3) Cell counting kit-8 findings indicated that lentivirus transfection of Scleraxis gene showed no influence on the cell growth rate. (4) Real-time fluorescent quantitative PCR findings showed that the mRNA expression of Scleraxis and ligament-related genes type I collagen, type III collagen, Fibronectin and Tenascin-C was significantly increased after lentivirus transfection of Scleraxis gene. (5) The results of immunofluorescence showed that the expression levels of ligament-related proteins type I collagen, type III collagen, Fibronectin and Tenascin-C were increased after lentivirus transfection of Scleraxis gene. To conclude, in vivo animal experiments have confirmed that the lentivirus transfection of Scleraxis gene can accelerate the tendon-bone healing of the rabbit extraarticular tendon-bone model.