To construct the recombinant adeno-associated virus （rAAV） vector with human bone morphogenetic protein 7 （BMP7） and observe the BMP7 mRNA expression in vitro, BMP7 CDS sequence was cloned into expression plasmid ...To construct the recombinant adeno-associated virus （rAAV） vector with human bone morphogenetic protein 7 （BMP7） and observe the BMP7 mRNA expression in vitro, BMP7 CDS sequence was cloned into expression plasmid pAAV-MCS of AAV Helper Free System. The recombinant plasmid was identified with enzyme digestion and sequencing. The recombinant plasmid, pAAV-RC, pHelper were co-transfected into AAV-293 cells according to the calcium phosphate-based protocol. The viral stock was collected by 4 rounds of freeze/thaw. After purified and concentrated, the recombinant virus titer was determined by dot-blot assay. HEK293 cells were transfected with the recombinant virus at different MOI, and the expression of BMP7 mRNA was detected by RT-PCR. The results showed rAAV-BMP7 was constructed and packaged successfully. The physical particle titer was 2.5×10^11 vector genomes/mL. There was different expression level of BMP7 mRNA after transfecton. These data suggested that recombinant AAV mediated a stable expression of hBMP7 mRNA in 293 cells. The AAV production method may pave the way of an effective strategy for the jaw bone defection around dental implants.展开更多
目的探讨用人骨形态发生蛋白7(human bone morphogenetic protein 7,hBMP7)基因修饰的犬髓核细胞与同种异体椎间盘复合后体内原位移植的方法阻止或延缓同种异体椎间盘移植后退变的能力。方法将18个比格犬椎间盘(L_(4-5))置于-196℃冻存...目的探讨用人骨形态发生蛋白7(human bone morphogenetic protein 7,hBMP7)基因修饰的犬髓核细胞与同种异体椎间盘复合后体内原位移植的方法阻止或延缓同种异体椎间盘移植后退变的能力。方法将18个比格犬椎间盘(L_(4-5))置于-196℃冻存液中保存2个月,随机分为A、B、C三组,A组以r AAV2-hBMP7转染犬髓核细胞,将能够表达hBMP7蛋白的髓核细胞悬液(5×10~6个/ml,20μl)注射入复温后的椎间盘中体外培养,B组以相同数量未转染的hBMP7的髓核细胞注入椎间盘后体外培养,C组以20μl DMEM/F12细胞培养液生理盐水注射后体外培养。将培养7d的3组椎间盘分别移植至15只比格犬的L4-5,在术前、术后即刻及术后1、3、6个月通过X线检测移植椎间盘的愈合情况及其高度变化;通过MRIT2像分析椎间盘的退变情况;术后6个月时处死动物取材,分析腰椎屈伸、侧弯及扭转的生物力学变化;组织学染色检测椎间盘的结构及退变情况;PCR法检测3组髓核组织中hBMP7 mRNA的表达。结果X线检测显示3组移植椎间盘高度变化指数(DHVI)差异无统计学意义(P>0.05);MRI检测结果显示:在术后12、24周时,B、C两组移植椎间盘的MRIT2像信号灰度比明显低于A组(P<0.05);生物力学检测结果显示:C组的左右扭转度明显大于A、B组(P<0.05),而A、B两组间的差异无统计学意义(P>0.05),而对屈伸及侧弯活动度检测发现3组间差异无统计学意义;PCR检测结果显示:6个月时A组仍可检测到hBMP mRNA的高表达;组织学检测结果显示:移植后6个月时仍有外源性髓核细胞存活,A组相对于B、C两组髓核结构更加完整,所含细胞外基质更多。结论表达hBMP7的髓核细胞能阻止同种异体椎间盘移植后的退变性。展开更多
AIM To present the incidence of heterotopic ossification after the use of recombinant human bone morphogenetic protein-7(rhB MP-7) for the treatment of nonunions.METHODS Bone morphogenetic proteins(BMPs) promote bone ...AIM To present the incidence of heterotopic ossification after the use of recombinant human bone morphogenetic protein-7(rhB MP-7) for the treatment of nonunions.METHODS Bone morphogenetic proteins(BMPs) promote bone formation by auto-induction. Recombinant human BMP-7 in combination with bone grafts was used in 84 patients for the treatment of long bone nonunions. All patients were evaluated radiographicaly for the development of heterotopic ossification during the standard assessment for the nonunion healing. In all patients(80.9%) with radiographic signs of heterotopic ossification, a CT scan was performed. Nonunion site palpation and ROM evaluation of the adjacent jointswere also carried out. Factors related to the patient(age, gender), the nonunion(location, size, chronicity, number of previous procedures, infection, surrounding tissues condition) and the surgical procedure(graft and fixation type, amount of rhB MP-7) were correlated with the development of heterotopic ossification and statistical analysis with Pearsons χ~2 test was performed.RESULTS Eighty point nine percent of the nonunions treated with rh BMP-7, healed with no need for further procedures. Heterotopic bone formation occurred in 15 of 84 patients(17.8%) and it was apparent in the routine radiologi-cal evaluation of the nonunion site, in a mean time of 5.5 mo after the rh BMP-7 application(range 3-12). The heterotopic ossification was located at the femur in 8 cases, at the tibia in 6, and at the humerus in οne patient. In 4 patients a palpable mass was present and only in one patient, with a para-articular knee nonunion treated with rhB MP-7, the size of heterotopic ossification affected the knee range of motion. All the patients with heterotopic ossification were male. Statistical analysis proved that patient's gender was the only important factor for the development of heterotopic ossification(P = 0.007). CONCLUSION Heterotopic ossification after the use of rh BMP-7 in nonunions was common but it did not compromise the final clinical ou展开更多
基金a grant from National Natural Sciences Foundation of China (No. 30572065/ C03031103)
文摘To construct the recombinant adeno-associated virus （rAAV） vector with human bone morphogenetic protein 7 （BMP7） and observe the BMP7 mRNA expression in vitro, BMP7 CDS sequence was cloned into expression plasmid pAAV-MCS of AAV Helper Free System. The recombinant plasmid was identified with enzyme digestion and sequencing. The recombinant plasmid, pAAV-RC, pHelper were co-transfected into AAV-293 cells according to the calcium phosphate-based protocol. The viral stock was collected by 4 rounds of freeze/thaw. After purified and concentrated, the recombinant virus titer was determined by dot-blot assay. HEK293 cells were transfected with the recombinant virus at different MOI, and the expression of BMP7 mRNA was detected by RT-PCR. The results showed rAAV-BMP7 was constructed and packaged successfully. The physical particle titer was 2.5×10^11 vector genomes/mL. There was different expression level of BMP7 mRNA after transfecton. These data suggested that recombinant AAV mediated a stable expression of hBMP7 mRNA in 293 cells. The AAV production method may pave the way of an effective strategy for the jaw bone defection around dental implants.
文摘目的探讨用人骨形态发生蛋白7(human bone morphogenetic protein 7,hBMP7)基因修饰的犬髓核细胞与同种异体椎间盘复合后体内原位移植的方法阻止或延缓同种异体椎间盘移植后退变的能力。方法将18个比格犬椎间盘(L_(4-5))置于-196℃冻存液中保存2个月,随机分为A、B、C三组,A组以r AAV2-hBMP7转染犬髓核细胞,将能够表达hBMP7蛋白的髓核细胞悬液(5×10~6个/ml,20μl)注射入复温后的椎间盘中体外培养,B组以相同数量未转染的hBMP7的髓核细胞注入椎间盘后体外培养,C组以20μl DMEM/F12细胞培养液生理盐水注射后体外培养。将培养7d的3组椎间盘分别移植至15只比格犬的L4-5,在术前、术后即刻及术后1、3、6个月通过X线检测移植椎间盘的愈合情况及其高度变化;通过MRIT2像分析椎间盘的退变情况;术后6个月时处死动物取材,分析腰椎屈伸、侧弯及扭转的生物力学变化;组织学染色检测椎间盘的结构及退变情况;PCR法检测3组髓核组织中hBMP7 mRNA的表达。结果X线检测显示3组移植椎间盘高度变化指数(DHVI)差异无统计学意义(P>0.05);MRI检测结果显示:在术后12、24周时,B、C两组移植椎间盘的MRIT2像信号灰度比明显低于A组(P<0.05);生物力学检测结果显示:C组的左右扭转度明显大于A、B组(P<0.05),而A、B两组间的差异无统计学意义(P>0.05),而对屈伸及侧弯活动度检测发现3组间差异无统计学意义;PCR检测结果显示:6个月时A组仍可检测到hBMP mRNA的高表达;组织学检测结果显示:移植后6个月时仍有外源性髓核细胞存活,A组相对于B、C两组髓核结构更加完整,所含细胞外基质更多。结论表达hBMP7的髓核细胞能阻止同种异体椎间盘移植后的退变性。
基金The European Union(European Social Fund-ESF)Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework(NSRF)-Research Funding Program:Heracleitus Ⅱ
文摘AIM To present the incidence of heterotopic ossification after the use of recombinant human bone morphogenetic protein-7(rhB MP-7) for the treatment of nonunions.METHODS Bone morphogenetic proteins(BMPs) promote bone formation by auto-induction. Recombinant human BMP-7 in combination with bone grafts was used in 84 patients for the treatment of long bone nonunions. All patients were evaluated radiographicaly for the development of heterotopic ossification during the standard assessment for the nonunion healing. In all patients(80.9%) with radiographic signs of heterotopic ossification, a CT scan was performed. Nonunion site palpation and ROM evaluation of the adjacent jointswere also carried out. Factors related to the patient(age, gender), the nonunion(location, size, chronicity, number of previous procedures, infection, surrounding tissues condition) and the surgical procedure(graft and fixation type, amount of rhB MP-7) were correlated with the development of heterotopic ossification and statistical analysis with Pearsons χ~2 test was performed.RESULTS Eighty point nine percent of the nonunions treated with rh BMP-7, healed with no need for further procedures. Heterotopic bone formation occurred in 15 of 84 patients(17.8%) and it was apparent in the routine radiologi-cal evaluation of the nonunion site, in a mean time of 5.5 mo after the rh BMP-7 application(range 3-12). The heterotopic ossification was located at the femur in 8 cases, at the tibia in 6, and at the humerus in οne patient. In 4 patients a palpable mass was present and only in one patient, with a para-articular knee nonunion treated with rhB MP-7, the size of heterotopic ossification affected the knee range of motion. All the patients with heterotopic ossification were male. Statistical analysis proved that patient's gender was the only important factor for the development of heterotopic ossification(P = 0.007). CONCLUSION Heterotopic ossification after the use of rh BMP-7 in nonunions was common but it did not compromise the final clinical ou
