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BACKGROUND: Acellular amniotic membrane scaffold is a natural scaffold with good biocompatibility, which has been widely used in tissue engineering. Scleraxis can promote the differentiation of human amniotic mesenchymal stem cells into human ligament cells and promote tendon-bone healing. OBJECTIVE: To explore whether acellular amniotic membrane scaffold combined with human amniotic mesenchymal stem cells transfected with Scleraxis can promote rabbit tendon-bone healing. METHODS: (1) Human amniotic mesenchymal stem cells were isolated and cultured in vitro. After passaged, the cell morphology was observed. (2) The Scleraxis lentivirus was constructed in vitro and then transfected into passage 3 human amniotic mesenchymal stem cells with optimal multiplicity of infection. The transfection efficiency was detected by q-PCR. (3) The acellular amniotic membrane scaffold was prepared by enzymatic digestion. Then the Scleraxis lentivirus-transfected cells were seeded on the acellular amniotic membrane scaffold in vitro. The cell growth on the scaffold was observed by phalloidin staining. (4) The New Zealand white rabbit tendon was covered with the acellular amniotic membrane scaffold combined with human amniotic mesenchymal stem cells transfected with Scleraxis lentivirus, followed by implanted into the bone tunnel. The tendon-bone healing was detected. RESULTS AND CONCLUSION: The passage 3 human amniotic mesenchymal stem cells adhered well. (2) After transfected with Scleraxis lentivirus for 96 hours, stable green fluorescence was observed. The mRNA expression level of Sclerxis was significantly increased, indicating a success transfection. The epithelial cells of the acellular amniotic membrane scaffold disappeared, indicating a relatively complete decellularization. The basal layer remained intact, and the extracellular matrix component still existed. Phalloidin staining results revealed that the cells on the acellular amniotic membrane scaffold were in good adhesion and growth, and the cell proliferation was not affected. Therefore, In vivo experimental results reveal that human acellular amniotic scaffold combined with human amniotic mesenchymal stem cells transfected with Scleraxis lentivirus can promote the tendon-bone healing.
ABSTRACT
Objective To study the effect of repairment of articular cartilage defects in non weight-bearing area of rabbit with bone marrow-derived mesenchymal stem cells (BMSCs) seeded on human acellular amniotic membrane (HAAM).Methods From July 2012 to March 2013,bone marrow-derived mesenchymal stem cells were isolated and purified from rabbit in vitro.The cells were seeded on human acellular anniotic membrane at the concentration of 1.63 × l05/cm2.From 7 days to 8 days after cultured,the complexes of BMSC and HAAM were examined under electronmicroscope,light microscope and by HE stain.Full thickness empty defects measuring 4 mm in diameter by 3 mm depth were prepared in femoral intercondylar fossa of 24 rabbits.The rabbits were randomized into two groups:group A and group B with 12 each group.The defects of right knees were served as control and the left as experimental group.BMSCs/HAAM composite was cultured and then transplanted into the defect of left knee joint in group A as group BMSCs/HAAM and HAAM into group B as group HAAM.These rabbits were killed at 4 and 12 weeks after surgery in each group and the newly cartilage samples were evaluated grossly,histologically are graded.Results In the 4th and 12th week after the operation,the regenerated tissue were white,soft and smooth.Chondrocytes were found in the tissue In the 12th week,the morphology,distribution and arrangement of the regenerated tissues were similar to normal cartilage in the knees with HAAM-BMSCs transplantation.The regenerated tissues grew to be integrated with the surrounding normal cartilage with obscure boundary between them.Chondrocytes were found in all layer of the tissue,surrounding normal cartilage with obscure boundary between them.In the HAAM transplantation,the rough surface of regenerated tissue sunk obviously and the fibmblasts in all layer were found.While there were no regenerated tissue in the control side.Conclusion BMSCs seeded on HAAM could repair the articular cartilage defects of femoral intercondylar fossa from rabbits.
ABSTRACT
Objective To investigate the biocompatilility of human acellular amniotic membrane(HAM) with vascular smooth muscle cells(VSMCs) and to explore the possibility to construct tissue engineering bladder with HAM as the scaffold and VSMCs as the seed cells. Methods After physical and 1% trypsogen preparation,the HAM was mixed with VSMCs taken from rats for culture in vitro.Histological obserbation was done under inverted microscope and scanning electron microscope respectively.20 rats were divided into two groups.Hemicystectomies were performed in 20 rats,and 10 of them were repaired with HAM grafts with VSMCs on the half bladder,the other 10 were repaired with HAM grafts without VSMCs as the control group.The rats underwent postoperative assessment of bladder volume at the 2nd,4th and 8th weeks,and the grafts were observed by light microscope at the 2nd,4th and 8th weeks after surgery. Results The physical and 1% trypsogen treated HAM was pure with hollows and undamaged collagen fibers.The VSMCs could grow,adhere to and differentiate on the surface of HAM and into the hollows.At the 2nd,4th and 8th weeks after surgery, the bladder volumes of the experimental group were not different significantly compared with those of the control group.Epithelialization and smooth muscle cells regeneration occurred with the infiltration of inflammatory cells in the 2nd week after grafting,and the HAM were absorbed.In the 4th and 8th weeks,it was difficult to delineate the junction between the host bladder and grafts by histology.Conclusion HAM can be used as the scaffold to construct tissue engineering bladder as it has good biocompatibility with VSMCs without disturbing the cell form and the graft can be absorbed quickly.