腺病毒介导人骨形态蛋白-7基因抑制去势大鼠骨质疏松的实验研究

[目的] 探讨腺病毒介导骨形态蛋白-7基因转染对去势大鼠骨质疏松的抑制作用。[方法] 用外科去势的方法造成大鼠骨质疏松动物模型，用腺病毒介导的骨形态蛋白-7基因通过椎体髓腔注射的方法转移至大鼠椎体内，骨干重测量来检测全身骨丢失的情况；骨组织形态学观察椎体骨小梁骨质疏松的情况；骨形态定量方法评价椎体骨小梁的动静态指标的变化情况。[结果] 术后1个月的骨干重的测量显示注入AdBMP-7组的动物骨量明显大于其余各组；骨形态学检测结果显示注入AdBMP-7的椎体骨小梁结构较完整，而其余各组的骨小梁变细、断裂。5周后用骨形态定量进行检测显示AdBMP-7基因注入的椎体的各项动静态指标都明显优于其余各组椎体。[结论] 腺病毒介导BMP-7基因植入去势大鼠椎体髓腔可以分泌BMP-7，并可以在早期阻止去势大鼠的骨质疏松。     

应用AdEasy腺病毒载体系统构建人骨形成蛋白2基因重组腺病毒

目的利用AdEasy腺病毒载体系统构建人骨形成蛋白2(BMP2)基因重组腺病毒并在293E细胞中扩增制备重组病毒。方法自人骨形成蛋白2真核表达载体pcDNA3-hBMP2中酶切出hBMP2基因，插入pAdtrackCMV中构建成腺病毒穿梭质粒pAdtrackCMV—hBMP2，经酶切线性化后，采用电穿孔转化到事先电转化腺病毒骨架质粒pAdEasy的BJ5183大肠杆菌电感受态细菌中，挑选同源重组质粒，酶切线性化重组质粒并转染293E细胞包装成重组病毒颗粒，荧光显微镜观察绿色荧光表达。重组病毒上清感染293细胞，荧光显微镜观察绿色荧光表达。结果经限制性内切酶检测和GFP表达证实成功地构建了携带hBMP2基因的重组腺病毒载体并制备出高滴度重组病毒。结论成功地构建了携带hBMP2基因的重组腺病毒载体，为进一步研究rBMP2基因治疗奠定了基础。     

腺病毒介导的LacZ基因在大鼠坐骨神经的表达

目的 :观察腺病毒介导的LacZ基因在大鼠坐骨神经雪旺细胞 (Schwanncells ,SCs)的表达。方法 :大鼠坐骨神经内直接注射报告基因LacZ重组腺病毒 (Ad LacZ) ,X gal组织化学染色检测LacZ基因的表达 ,采用LEICAM 5 5 0型图像分析仪对坐骨神经切片X gal染色强弱进行定量评价。结果 :将滴度为 1× 10 8PFU /ml的Ad LacZ病毒液 10 μl注入坐骨神经 2d后即可检测到LacZ的表达 ,7～ 14d表达显著增加 (与 2d组比较P <0 .0 1) ,7d组与 14d组表达量无显著差异 (P >0 .0 5 ) ,2 8d时SCs蓝染又减弱 (与 7d组和 14d组比较P <0 .0 1)。注射生理盐水的对照组X gal染色阴性。结论 :腺病毒介导的LacZ基因可转入活体动物坐骨神经内并高效表达 ,表明腺病毒介导神经营养因子等基因治疗有促进周围神经损伤再生的作用。     

骨形成蛋白2重组腺病毒的构建与鉴定

目的　通过构建骨形成蛋白 (BMP)重组腺病毒 ,为骨缺损的基因治疗提供可能。方法　应用逆转录 聚合酶链反应 (RT PCR)法克隆出BMP2全长基因 ,构建重组腺病毒载体 ,DNA 磷酸钙共沉法将辅助质粒PJM 17转染 2 93细胞 ,同源重组构建出重组腺病毒。测滴度并用氯化铯梯度离心纯化备用。结果　逆转录克隆出BMP2全长基因 1.2kb ,测序后连接于重组腺病毒载体 ,酶切鉴定后转染构建活病毒 ,再次感染 2 93细胞扩增 ,测滴度为× 10E10 pfu/ml ,并应用PCR法测定目的序列。结论　BMP2重组腺病毒的构建为骨缺损等疾病的基因治疗提供可能     

腺病毒介导的NT-3基因在骨髓间质干细胞中的表达

目的:研究腺病毒介导的NT-3基因在培养的大鼠骨髓间质干细胞(mesenchymal stem cells,MSCs)中的表达.方法:在293细胞中培养扩增NT-3重组腺病毒(adenovirus vector for NT-3,Ad-NT-3),测定病毒滴度,然后用Ad-NT-3感染传代培养的MSCs,RT-PCR技术检测NT-3基因的表达.结果:Ad-NT-3扩增后获得了较高滴度的病毒,MSCs经Ad-NT-3感染后有NT-3 mRNA的转录.结论:腺病毒介导的NT-3基因可转入培养的MSCs并高效表达,为NT-3基因治疗的研究奠定了基础.     

腺病毒介导的 NT- 3基因在大鼠坐骨神经的表达

目的观察腺病毒介导的神经营养素-3(neurotrophin-3,NT-3)基因在大鼠坐骨神经雪旺细胞(Schwanncells,SCs)的表达。方法NT-3重组腺病毒在293细胞中培养繁殖并测定滴度后,直接注入大鼠损伤修复的坐骨神经内,不同时间点取材,采用免疫组织化学染色检测NT-3蛋白的表达,并用LEICAM550型图像分析仪对坐骨神经切片NT-3免疫组化染色强弱进行定量评价。结果坐骨神经损伤修复后直接注射Ad-NT-3,2d后出现NT-3免疫组化染色阳性产物,主要位于吻合口附近,阳性产物呈平行条纹状排列,7d时显著增加(与2d组相比,P<0.01),14d和28d时有所下降(与7d组相比,P<0.01),两者差异无显著性意义(P>0.05),但与2d组相比,仍维持在较高的水平(P<0.01)。而正常坐骨神经、损伤修复后注射Ad-LacZ或生理盐水的坐骨神经NT-3免疫组化染色结果为阴性。结论NT-3基因能通过腺病毒介导转入损伤修复后周围神经的SCs并表达NT-3蛋白,为腺病毒介导神经营养因子基因治疗促进周围神经损伤再生提供了初步的理论和实验依据。     

重组Akt腺病毒的构建及其在肝硬化大鼠肝脏中的表达

目的:探讨持续活化Akt且带有HA标签(myr-HA-Akt)基因的重组腺病毒在肝硬化大鼠肝脏中的表达特性。方法:酶切正向插入目的基因的真核表达载体pcDNA3.1-myr-HA-Akt,获得myr-HA-Akt cDNA后，将其定向克隆到穿梭质粒pDC316中,然后将重组质粒与病毒骨架质粒pBHGloxΔE1,3Cre共转染293 细胞,获得复制缺陷型重组腺病毒Ad-myr-HA-Akt,并进行扩增、纯化。通过观察腺病毒感染293细胞后是否出现细胞病变效应;PCR和基因测序方法对所构建病毒进行鉴定，并采用TCID50法检测病毒滴度。自尾静脉注射重组腺病毒Ad-myr-HA-Akt感染肝硬化模型大鼠。免疫印迹法检测大鼠肝组织内Akt 和p-Akt蛋白的表达。结果:感染的293 细胞出现明显的细胞病变效应，PCR产物电泳证实重组腺病毒的存在，基因测序证实myr-HA-Akt的cDNA正确插入穿梭质粒且与pBHGloxΔE1,3Cre正确同源重组;病毒滴度为5.5×1011 vp/mL。从蛋白水平证实感染病毒的肝硬化模型大鼠有外源性Akt基因的表达。结论:构建的重组腺病毒Ad-myr-HA-Akt能有效地感染肝硬化模型大鼠,并可在模型大鼠中正确转录和翻译，为进一步研究腺病毒介导的Akt基因对肝硬化的治疗奠定了实验基础。     

白介素-10基因治疗重症急性胰腺炎的实验研究

目的:探讨重组腺病毒质粒介导的人白细胞介素10(IL10)基因对大鼠重症急性胰腺炎的治疗效果。方法:构建IL10的腺病毒质粒,将其注入健康大鼠腹腔内,检测胰、肝、肺组织内IL10的表达和血清淀粉酶的变化。用5%的牛磺胆酸钠诱发大鼠的重症急性胰腺炎;将IL10腺病毒注入胰腺炎大鼠腹腔内,检测大鼠血清淀粉酶及胰、肝、肺组织内IL10的变化;组织切片观察胰腺组织的病理变化。对照组用空载体和PBS溶液注入腹腔。结果:IL10在健康大鼠组织内有高浓度的表达,转染大鼠并不引起炎症反应。用IL10腺病毒基因治疗24h后,胰腺炎大鼠血清淀粉酶明显降低于对照组;胰、肝、肺组织内的IL10浓度明显高于对照组;TNFα的表达明显低于另两组;病理切片显示治疗组胰腺的炎症改变轻微,而对照组却呈现出血坏死性变化。结论:重组腺病毒介导的人IL10基因治疗可以显著地抑制重症急性胰腺炎的病变,降低死亡率。     

Smad 6和Smad 7基因治疗对肾小管间质纤维化进程的影响

目的 观察腺相关病毒(rAAV)介导的Smad6和Smad7基因治疗对单侧输尿管梗阻性(LIUO)肾小管间质纤维化进程的影响。方法 构建产生表达Smad6和Smad7基因的无辅毒腺相关病毒载体，再将此病毒颗粒通过肾动脉途径转移到UUO模型。30只Wistar大鼠随机分为假手术组、梗阻组、LacZ AAV转染组、Smad6 AAV转染组和Smad7 AAV转染组(n=6)，于术后第3周处死大鼠。采用β-半乳糖苷酶染色和免疫组化观察外源基因的定位，Western印迹法观察外源基因、胞内磷酸化Smad2、PAI-1和α-SMA的表达；底物酶谱法检测MMP-2和MMP-9活性，分光光度法测定肾组织羟脯氨酸含量。结果 Smad6和Smad7成功地转染到外髓的肾小管间质区，定位在肾小管和集合管细胞，而血管细胞、肾小球或间质细胞均未见有AAV转移基因的表达。Smad7基因治疗可显著降低肾组织PAI-1、α-SMA的表达和肾组织羟脯氨酸含量，增加MMP-2和MMP-9活性，这些作用与Smad7阻断Smad2磷酸化有关。相反，Smad6没有这样的治疗作用。结论 Smad7基因转移能有效缓解单侧输尿管梗阻肾小管间质纤维化，AAV介导的Smad7基因转移有望成为治疗肾小管间质纤维化的方法之一。     

腺病毒介导的NT—3基因在大鼠从骨神经的表达

目的观察腺病毒介导的神经营养素 - 3(neurotrophin- 3,NT- 3)基因在大鼠坐骨神 经雪旺细胞 ( Schwann cells,SCs) 的表达.方法 NT- 3重组腺病毒在 293细胞中培养繁殖并 测定滴度后,直接注入大鼠损伤修复的坐骨神经内,不同时间点取材,采用免疫组织化学染 色检测 NT- 3蛋白的表达,并用 LEICA M550型图像分析仪对坐骨神经切片 NT- 3免疫组化染色 强弱进行定量评价.结果坐骨神经损伤修复后直接注射 Ad- NT- 3,2 d后出现 NT- 3免疫组化 染色阳性产物,主要位于吻合口附近,阳性产物呈平行条纹状排列,7 d时显著增加 ( 与 2 d组相比,P< 0.01),14 d和 28 d时有所下降 ( 与 7 d组相比,P< 0.01),两者差异无显著 性意义 ( P >0.05),但与 2 d组相比,仍维持在较高的水平 ( P< 0.01).而正常坐骨神经、 损伤修复后注射 Ad- LacZ或生理盐水的坐骨神经 NT- 3免疫组化染色结果为阴性.结论 NT- 3基因能通过腺病毒介导转入损伤修复后周围神经的 SCs并表达 NT- 3蛋白,为腺病毒介导神经 营养因子基因治疗促进周围神经损伤再生提供了初步的理论和实验依据.     

骨形态发生蛋白2基因治疗在修复骨缺损中对血管化影响的实验研究

目的观察骨形态发生蛋白-2（BMP-2）基因治疗在修复骨缺损中对血管化的影响。方法分离培养兔骨髓基质干细胞（MSCs），经BMP-2腺病毒载体转染后复合异种骨支架移植修复1．5cm桡骨缺损。分为5组：①BMP-2基因转染细胞＋去抗原牛松质骨支架（BCB）；②未转染细胞＋重组BMP-2＋BCB；③对照基因转染细胞＋BCB；④未转染细胞＋BCB；⑤BCB。术后4、8、12周行微血管墨汁灌注、血管内皮生长因子（VEGF）免疫组化染色、组织学等检测。结果术后4周，基因治疗组骨间血管的密度在周边区域较高，通常每一个骨小梁孔隙中都有一支新形成的小血管；透射电镜见成骨细胞总是毗邻血管内皮细胞而存在，并随着微血管的增生而逐渐向骨细胞发展；间质细胞VEGF表达明显增强。结论BMP-2基因治疗可通过上调VEGF表达，间接诱导移植骨血管化，对骨不连、骨缺损的治疗具有重要意义。     

BMP-2基因转染的人骨髓基质干细胞复合PLA/PCL支架体外构建组织工程骨

目的　用人骨形态发生蛋白 2腺病毒表达载体 (Ad -BMP - 2 )转染的人骨髓基质干细胞 (hBMSC) ,复合PLA/PCL(聚乳酸 /聚己内酯 )生物降解支架体外构建组织工程骨。方法　用Ad -BMP - 2转染体外培养的成人BMSC ,免疫组化、原位杂交染色和蛋白印迹方法检测细胞BMP - 2的表达 ,并通过流式细胞仪和ALP活性检测分析其对细胞增殖、分化的影响。然后将转染后细胞接种到PLA/PCL支架上 ,扫描电镜观察细胞贴附、生长状况。结果　转染后 ,hBMP - 2基因在mRNA水平和蛋白水平均有表达 ;S期细胞比例和ALP活性明显增高。扫描电镜见转染细胞分布均匀 ,伸展良好。结论　Ad-BMP - 2可高效转染hBMSC ,且促进细胞增殖及成骨转化。转染后细胞在PLA/PCL上生长良好 ,BMP - 2基因治疗的组织工程骨构建成功     

Bone induction by BMP-2 transduced stem cells derived from human fat.

PURPOSE: We have isolated pluripotent mesenchymal progenitor cells in large numbers from liposuction aspirates (processed lipoaspirate cells or PLAs). This study examines the osteogenic potential of PLAs and bone marrow aspirate cells (BMAs), when exposed to either recombinant human bone morphogenetic protein (BMP)-2 (rh-BMP-2) or adenovirus containing BMP-2 cDNA (Ad-BMP-2). METHODS: Liposuction aspirates underwent proteolytic digestion to obtain PLAs. After exposure to exogenous rh-BMP-2 or Ad-BMP-2 for four or seven days, PLAs and BMAs were assessed by histochemistry, spectrophotometry and RT-PCR. Western blotting and ELISA confirmed BMP gene transduction. Results were compared to osteoblasts and cells in osteogenic media only. PLA-Ad-BMP-2 cells were seeded on matrices and implanted in the hind limbs of SCID mice. RESULTS: Analysis of quantified bone precursor assays including extracellular ALP histomorphometry, intracellular ALP spectrophotometry, and calcified extracellular matrix (von Kossa) histomorphometry revealed that PLAs treated with exogenous rh-BMP-2 or transduced with a BMP-2 containing adenovirus (PLA-Ad-BMP-2) produced more bone precursors than osteoblasts (p=0.001). PLAs treated with exogenous rh-BMP-2 or PLA-Ad-BMP-2 also produced more bone precursors than BMAs (p=0.001), except for day 7 ALP histomorphometry (p=0.343). ELISA confirmed successful BMP-2 production by both progenitor cell groups transduced with Ad-BMP-2. H&E sections from collagen I matrices seeded with PLA-Ad-BMP-2 cells confirmed bone formation at six weeks. CONCLUSIONS: Liposuction aspirates contain PLAs that can be transfected with the BMP-2 gene, with rapid induction into the osteoblast phenotype at a rate comparable to rh-BMP-2 and osteoblast groups. Transduced PLAs produce more bone precursors with faster onset of calcified extracellular matrix than transduced BMAs. PLAs may be an ideal source of mesenchyme-lineage stem cells for gene therapy and tissue engineering.     

Effect of regional gene therapy with bone morphogenetic protein-2-producing bone marrow cells on spinal fusion in rats

BACKGROUND: Bone morphogenetic proteins (BMPs) are now being used as bone-graft substitutes to enhance spinal fusion. However, the large doses of BMP required to induce a spinal fusion in humans suggests that the delivery of these proteins should be improved. We used ex vivo adenoviral gene transfer to create BMP-2-producing bone marrow cells, and these autologous cells were found to induce a posterolateral fusion of the spine in syngeneic rats. METHODS: Intertransverse spinal arthrodesis (L4 and L5) was attempted in ten groups of Lewis rats with 5 x 10 (6) BMP-2-producing rat bone marrow cells (Ad-BMP-2 cells), created through adenoviral gene transfer with guanidine hydrochloride-extracted demineralized bone matrix as a carrier (Group I); 5 x 10 (6) Ad-BMP-2 cells on a collagen sponge carrier (Group II); 10 micro g of recombinant BMP-2 (rhBMP-2) in a guanidine hydrochloride-extracted demineralized bone matrix carrier (Group III); 10 micro g of rhBMP-2 in a collagen sponge carrier (Group IV); autogenous iliac crest bone-grafting (Group V); 5 x 10 (6) beta-galactosidase-producing rat bone marrow cells, created through adenoviral gene transfer with guanidine hydrochloride-extracted demineralized bone matrix as a carrier (Group VI); decortication of the transverse processes alone (Group VII); 5 x 10 (6) uninfected rat bone marrow cells with a guanidine hydrochloride-extracted demineralized bone matrix carrier (Group VIII); guanidine hydrochloride-extracted demineralized bone matrix only (Group IX); or a collagen sponge alone (Group X). Each specimen underwent plain radiography, manual palpation, and histological analysis. RESULTS: All spines in Groups I and II (BMP-2-producing bone marrow cells) and all spines in Groups III and IV were fused at four weeks postoperatively. In contrast, none of the spines in the other groups had fused at a minimum of eight weeks after implantation. Histological analysis of the specimens revealed that the spines that had received BMP-2-producing bone marrow cells (Groups I and II) were filled with coarse trabecular bone postoperatively, whereas those that had received rhBMP-2 (Groups III and IV) were filled with thin, lace-like trabecular bone. All of the other spines, including those that had been treated with autogenous iliac crest bone-grafting (Group V), produced little or no new bone. CONCLUSION: BMP-2-producing bone marrow cells, created by adenoviral gene transfer, produce sufficient BMP to induce an intertransverse fusion in the rat spine model.     

转染BMP-2基因的兔BMSCs种植PLA/PCL支架体外构建组织工程骨

目的:用腺病毒载体将人骨形态发生蛋白-2(BMP-2)基因导入兔骨髓基质干细胞(BMSCs),种植PLA/PCL(聚乳酸/聚己内酯)支架体外构建组织工程骨.方法:蛋白印迹法检测转染后细胞BMP-2的表达,流式细胞仪和ALP活性检测分析基因转染对细胞增殖分化的影响.然后将转染后细胞接种到PLA/PCL支架上,扫描电镜观察细胞贴附、生长状况.结果:转染后,BMSCs表达BMP-2,S期细胞比例和ALP活性明显增高.扫描电镜见转染细胞分布均匀,伸展良好.结论:BMP-2基因转染BMSCs,可促进细胞增殖分化.转染后细胞在PLA/PCL支架上生长良好,BMP-2基因治疗的组织工程骨构建成功.     

不同移植途径对大鼠骨髓干细胞迁移至肝脏及分化的影响

目的 探讨门静脉、尾静脉和肝动脉3种移植途径下大鼠骨髓干细胞迁移至肝脏及向肝细胞分化的情况.方法 取30只正常SD大鼠,采用2-乙酰氨基芴和四氯化碳溶液灌胃,制成急性肝损伤模型,取其骨髓,以淋巴细胞分离液分离出干细胞,再用荧光染料(PKH26)进行标记.将此30只急性肝损伤大鼠分为3组,每组10只,门静脉输注组大鼠麻醉后,取腹部正中切口,经门静脉注入自体骨髓干细胞悬液0.4 ml(4×106个,下同);尾静脉输注组大鼠经尾静脉注人自体骨髓干细胞悬液0.4 ml;肝动脉输注组大鼠麻醉后,取腹部正中切口,将胃十二指肠动脉远端结扎,用动脉夹阻断肝总动脉血流,迅速在胃十二指肠动脉结扎点前方进针,注入自体骨髓干细胞悬液0.4 ml.骨髓干细胞移植后2周,取各组肝脏组织,制成冰冻切片,再以用异硫氰基荧光素标记的抗体进行免疫组织化学染色,检测其PKH26标记阳性细胞以及自蛋白和CK18的表达情况.结果 各组大鼠肝脏切片中均可见散在的PKH26染色阳性的红色荧光,门静脉输注组、尾静脉输注组及肝动脉输注组PKH26染色阳性细胞数分别为(58.0±2.67)个、(57.8±3.04)个及(58.3±3.52)个,三组间的差异无统计学意K(P>0.05).各组肝组织切片均广泛表达白蛋白及CK18(绿色荧光),荧光显微镜下可见同时发绿色荧光和红色荧光的细胞(绿色荧光与红色荧光相叠加而成的黄色荧光).结论 经门静脉、尾静脉和肝动脉注入的骨髓干细胞均能定植于肝脏,并在损伤的肝脏中分化为肝细胞,3种途径的效果相当.     

骨形成蛋白2基因修饰的老年大鼠骨髓间充质干细胞成骨分化能力的研究

目的观察年龄因素对骨髓间充质干细胞(marrow mesenchymal stem cells, MSCs)成骨分化能力的影响;了解基因治疗对老年大鼠MSCs成骨分化能力的影响. 方法 1月龄(幼年组)、9月龄(成年组)及24月龄(老年组)雄性Wistar大鼠各6只,取MSCs经体外分离、培养及携带骨形成蛋白2(bone morphogenetic protein 2,BMP-2)基因的腺病毒载体(Ad-BMP-2)转染后,定量检测BMP-2、碱性磷酸酶(alkaline phosphate,ALP)表达,以及成骨细胞标志性蛋白:Ⅰ型胶原、骨涎蛋白(bone sialoprotein,BSP)和骨桥素(osteopontin, OPN)的表达.将转染的各组MSCs分别与磷酸三钙(tricalcium phosphate, TCP)复合后植入裸鼠体内,3周后取材,比较各组诱导异位成骨能力. 结果 ELISA检测表明BMP-2基因修饰的MSCs可以有效表达BMP-2,且表达量在各年龄组间差异无统计学意义(P>0.05);各组ALP于诱导后第9天达高峰,但组间差异均无统计学意义(P＞0.05);诱导后第7天,RT-PCR半定量检测示各组均有成骨细胞特征性蛋白,即:Ⅰ型胶原、OPN及BSP的明显表达,表达量在各组间差异无统计学意义(P>0.05);BMP-2基因转染的MSCs与TCP复合后可诱导裸鼠体内异位成骨,各组成骨量差异无统计学意义(P>0.05). 结论 BMP-2基因修饰的老年大鼠MSCs可以恢复成骨分化能力,基因治疗可能为老年性骨骼疾病提供一种新的治疗途径.     

Evaluation of Ad-BMP-2 for enhancing fracture healing in an infected defect fracture rabbit model.

The objective of this study was to evaluate the use of adenoviral transfer of the BMP-2 gene (Ad-BMP-2) for enhancing healing in an infected defect fracture model. A femoral defect stabilized with plates and screws was surgically created in sixty-four skeletally mature New Zealand white rabbits. Experimental groups were: (1) non-infected Ad-luciferase (Ad-LUC, NONLUC), (2) non-infected Ad-BMP-2 (NONBMP), (3) infected Ad-LUC (INFLUC), and (4) infected Ad-BMP-2 (INFBMP). A sclerosing agent was applied to the ends of the bone at surgery to facilitate the development of osteomyelitis. Fracture healing was evaluated radiographically and histologically. Data were analyzed using an ANOVA, with statistical significance set as p<0.05. Rabbits in the non-infected and infected groups that were treated with Ad-BMP-2 had earlier initial- and bridging-callus formation, and a higher overall external callus grade compared to rabbits in the Ad-LUC groups. Rabbits in the Ad-LUC groups had more defect ossification compared to rabbits in the Ad-BMP-2 groups. There was a trend for rabbits in the Ad-BMP-2 group that were euthanized at 2 and 4 weeks after surgery to have more bone and cartilage compared to rabbits in the Ad-LUC group. The results of this study suggest that Ad-BMP-2 enhances the early stages of healing in an infected defect fracture. The results of our study were not as favorable as those reported in previous studies because animals healed by a large bridging callus and not by defect ossification. This could have been a result of the sclerosing agent, which may have damaged the cells in the defect.     

Ex vivo bone morphogenetic protein-9 gene therapy using human mesenchymal stem cells induces spinal fusion in rodents

OBJECTIVE: Ex vivo gene therapy with the use of human mesenchymal stem cells (hMSCs) and bone morphogenetic protein (BMP) genes provides a local supply of precursor cells and a supraphysiological dose of osteoinductive molecules that may promote bone formation in patients with inadequate hMSC populations because of age, osteoporosis, metastatic bone disease, iatrogenic depletion, or other metabolic derangements. This study was undertaken to evaluate the efficacy of ex vivo gene therapy with the use of hMSCs and the BMP-9 gene to promote spinal fusion in the rat. METHODS: Sixteen athymic nude rats were treated with hMSCs transduced with recombinant, replication-defective Type 5 adenovirus containing the cytomegalovirus promoter and either the BMP-9 (Ad-BMP-9) or the beta-galactosidase (Ad-beta-gal) gene. Ad-beta-gal served as the control. Each animal received a percutaneous, paraspinal injection of 10(6) hMSCs transduced with 50 plaque-forming units/cell adenovirus in the lumbar region, with Ad-BMP-9 on the left and Ad-beta-gal on the right. At 8 weeks postinjection, computed tomographic scans of the lumbosacral spine were obtained, and the lumbosacral spine specimens were examined histologically. RESULTS: Both computed tomographic studies and histological analysis clearly demonstrated large volumes of ectopic bone at the Ad-BMP-9-transduced hMSC injection sites, resulting in successful spinal fusion and no evidence of nerve root compression or local or systemic toxicity. The contralateral regions that were treated with Ad-beta-gal-transduced hMSCs showed no evidence of osteogenesis. CONCLUSION: The results of this study suggest that hMSC and BMP-9 ex vivo gene therapy may be useful in inducing spinal fusion as well as other related procedures and certainly warrants further clinical development.