Bone graft substitutes are widely used in the field of orthopedics and are extensively used to promote vertebral fusion. Fusion is the most common technique in spine surgery and is used to treat morbidities and reliev...Bone graft substitutes are widely used in the field of orthopedics and are extensively used to promote vertebral fusion. Fusion is the most common technique in spine surgery and is used to treat morbidities and relieve discomfort. Allograft and autograft bone substitutes are currently the most commonly used bone grafts to promote fusion. These approaches pose limitations and present complications to the patient. Numerous alternative bone graft substitutes are on the market or have been developed and proposed for application. These options have attempted to promote spine fusion by enhancing osteogenic properties. In this review, we reviewed biology of spine fusion and the current advances in biomedical materials and biological strategies for application in surgical spine fusion. Our findings illustrate that, while many bone graft substitutes perform well as bone graft extenders, only osteoinductive proteins(recombinant bone morphogenetic proteins-2 and osteogenic protein-1) provide evidence for use as both bone enhancers and bone substitutes for specific types of spinal fusion. Tissue engineered hydrogels, synthetic polymer composites and viral based gene therapy also holds the potential to be used for spine fusion in future, though warrants further investigation to be used in clinical practice.展开更多
Background Enhanced green fluorescent protein （EGFP） has been an important reporter gene for gene therapy. Human mesenchymal stem cells （hMSCs） are ideal target cells in cell transplantation and tissue engineering...Background Enhanced green fluorescent protein （EGFP） has been an important reporter gene for gene therapy. Human mesenchymal stem cells （hMSCs） are ideal target cells in cell transplantation and tissue engineering. We investigated their biological characteristics and differentiation mediated by PLEGFP-N1 retroviral transduction.Methods hMSCs were isolated from human bone marrow by density gradient fractionation and adherence to plastic flasks. Individual colonies were selected and cultured in tissue dishes. Packaging cells PT67 were transfected by PLEGFP-N1 retroviral vector , and hMSCs were transduced by viral supernatant infection. Meanwhile, hMSCs-EGFP were identified by immune phenotypes and whether it could differentiate into osteoblasts or adipocytes under conditioned media was investigated.Results The rate of stably transduced hMSCs-EGFP was up to 96% after being screened by G418. hMSCs-EGFP exhibited fibroblast-like morphological features. Flow cytometric analyses showed that hMSCs-EGFP were positive for CD73, CD105, CD166, CD90 and CD44, but negative for CD34 and CD45. In addition, it could functionally be induced into osteocytes or adipocytes under conditioned media. These biological features of hMSCs-EGFP were consistent with those of hMSCs.Conclusions hMSCs transduced by PLEGFP-N1 retroviral vector can be used in vivo securely because they can maintain their biological characteristics and differentiation. It is a simple and reliable way to trace the changes of hMSCs in vivo by EGFP during cell transplantation and gene therapy.展开更多
文摘Bone graft substitutes are widely used in the field of orthopedics and are extensively used to promote vertebral fusion. Fusion is the most common technique in spine surgery and is used to treat morbidities and relieve discomfort. Allograft and autograft bone substitutes are currently the most commonly used bone grafts to promote fusion. These approaches pose limitations and present complications to the patient. Numerous alternative bone graft substitutes are on the market or have been developed and proposed for application. These options have attempted to promote spine fusion by enhancing osteogenic properties. In this review, we reviewed biology of spine fusion and the current advances in biomedical materials and biological strategies for application in surgical spine fusion. Our findings illustrate that, while many bone graft substitutes perform well as bone graft extenders, only osteoinductive proteins(recombinant bone morphogenetic proteins-2 and osteogenic protein-1) provide evidence for use as both bone enhancers and bone substitutes for specific types of spinal fusion. Tissue engineered hydrogels, synthetic polymer composites and viral based gene therapy also holds the potential to be used for spine fusion in future, though warrants further investigation to be used in clinical practice.
基金This study was supported by a grant from the National 863 Program( No.2004AA205020 ), Doctoral Foundation of Ministry ofEducation (No.20020183064),and Scientific Foundation for YoungTeachers of Jilin University (No.419070100050).
文摘Background Enhanced green fluorescent protein （EGFP） has been an important reporter gene for gene therapy. Human mesenchymal stem cells （hMSCs） are ideal target cells in cell transplantation and tissue engineering. We investigated their biological characteristics and differentiation mediated by PLEGFP-N1 retroviral transduction.Methods hMSCs were isolated from human bone marrow by density gradient fractionation and adherence to plastic flasks. Individual colonies were selected and cultured in tissue dishes. Packaging cells PT67 were transfected by PLEGFP-N1 retroviral vector , and hMSCs were transduced by viral supernatant infection. Meanwhile, hMSCs-EGFP were identified by immune phenotypes and whether it could differentiate into osteoblasts or adipocytes under conditioned media was investigated.Results The rate of stably transduced hMSCs-EGFP was up to 96% after being screened by G418. hMSCs-EGFP exhibited fibroblast-like morphological features. Flow cytometric analyses showed that hMSCs-EGFP were positive for CD73, CD105, CD166, CD90 and CD44, but negative for CD34 and CD45. In addition, it could functionally be induced into osteocytes or adipocytes under conditioned media. These biological features of hMSCs-EGFP were consistent with those of hMSCs.Conclusions hMSCs transduced by PLEGFP-N1 retroviral vector can be used in vivo securely because they can maintain their biological characteristics and differentiation. It is a simple and reliable way to trace the changes of hMSCs in vivo by EGFP during cell transplantation and gene therapy.
