Objective Targeted adenoviral gene delivery from peripheral nerves was used to integrally analyse the characterization and time course of LacZ gene (AdLacZ) retrograde transfer to spinal cord and transgene product anterograde labeling ofperipheral nerve. Methods Recombinant replication-defective adenovirus containing AdLacZ was administrated to the cut proximal stumps of median and tibial nerves in Wister rats. Then the transected nerve was repaired with 10-0 nylon sutures. At different time point postinfection the spinal cords of C5 to T1 attached with DRGs and brachial plexuses, or L2 to L6 attached with DRGs and lumbosacralplexuses were removed. The removed spinal cord and DRGs were cut into 50 μm serialcoronal sections and processed for X-gal staining and immunohistochemical staining. The whole specimens of brachial or lumbosacral plexuses attaching with theirperipheral nerves were processed for X-gal staining. The number of X-gal stained neurons was counted and the initial detected time of retrograde labeling, peaktime and persisting period of gene expression in DRG sensory neurons, spinal cord motor neurons and peripheral nerves were studied. Results The gene transfer was specifically targeted to the particular segments of spinal cord andDRGs, and transgene expression was strictly unilaterally corresponding to the infected nerves. Within the same nerve models, the initial detected time of gene expression was earliest in DRG neurons, then in the motor neurons and latest in peripheral nerves. The persisting duration of β-gal staining was shortest in motor neurons, then in sensory neurons and longest in peripheral nerves. The initial detected time of β-gal staining in median nerve models was earlier in mediannerve models compared with that in the tibial nerve models. Although the initial detected time and the beginning of peak duration of β-gal staining were not same, the decreasing time of β-gal staining in motor and sensory neurons of thetwo nerve models were started at about the same day 8 post-infection. The labeled neurons were more in tibial nerve-models than that in median nerve models. Within the same models, the labeled sensory neurons of DRGs were morethan labeled motor neurons of ventral horn. The β-gal staining was tenser in median nerves than that in tibial nerves. However the persisting time of β-gal staining was longer in tibial nerve models. Conclusion The b gene expression in neurons and PNS renders this system particularly attractive for neuroanatomical tracing studies. Furthermore this gene delivery method allowing specific targeting of motor and sensory neurons without damaging the spinal cord might offer potentialities for the gene therapy of peripheral nerve injury.
Objective To construct replication-defective adenovirus containing tk gene (ADV-tk). Methods Recombinant adenovirus of ADV-tk was constructed using homologous recombination in cells. After the interested tk gene fragment in the recombinant plasmid obtained was confirmed by PCR, the titre of purified recombinant adenovirus was detected. In vitro study, tk gene in SMMC7721 cells transfected by ADV-tk was investigated by RT-PCR. In vivo study, ADV-tk was injected intraperitoneally into BALB/c nude mice with liver cancer and apoptosis cells in tumor were observed. Results Recombinant adenovirus containing ADV-tk was proved successfully. The titre of purified recombinant adenovirus was 1.4×1010 pfu/ml. In vitro study, tk was integrated and expressed by SMMC-7721 cells. In vivo study, with the injection of ADV-tk, apoptosis cells in tumor increased. Conclusion A replication-defective adenovirus containing tk gene is successfully constructed, which may useful for further research on tumor suicide gene therapy with ADV-tk.
ObjectiveTo compare the osteogenic effect of bone marrow mesenchymal stem cells (BMSCs) transfected by adenovirus-bone morphogenetic protein 2-internal ribosome entry site-hypoxia inducible factor 1αmu (Ad-BMP-2-IRES-HIF-1αmu) and by Ad-cytomegalovirus (CMV)-BMP-2-IRES-human renilla reniformis green fluorescent protein 1 (hrGFP-1) single gene so as to optimize the source of osteoblasts. MethodsBMSCs were separated and cultured from 1-month-old New Zealand white rabbit. The BMSCs at passage 3 were transfected by virus. The experiment was divided into 4 groups (groups A, B, C, and D) according to different virus: BMSCs were transfected by Ad-BMP-2-IRES-HIF-1αmu in group A, by Ad-CMV-BMP-2-IRES-hrGFP-1 in group B, by Ad-CMV-IRES-hrGFP-1 in group C, and BMSCs were not transfected in group D. The optimum multiplicity of infection (MOI) (50, 100, 150, and 200) was calculated and then the cells were transfected by the optimum MOI, respectively. The expression of BMP-2 gene was detected by immunohistochemistry staining after transfected, the expressions of BMP-2 protein and HIF-1α protein were detected by Western blot method. The osteogenic differentiation potential was detected by alkaline phosphatase (ALP) activity and Alizarin red staining. ResultsThe optimum MOI of groups A, B, and C was 200, 150, and 100, respectively. The expression of BMP-2 was positive in groups A and B, and was negative in groups C and D by immunohistochemistry staining; the number of positive cells in group A was more than that in group B (P ﹤ 0.05). The expression of BMP-2 protein in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). The expression of HIF-1α protein in group A was significantly higher than those in the other 3 groups (P ﹤ 0.05), no significant difference was found among the other 3 groups (P ﹥ 0.05). ALP activity in groups A and B was significantly higher than that in groups C and D (P ﹤ 0.05), group A was higher than group B (P ﹤ 0.05). Calcium nodules could be seen in groups A and B, but not in groups C and D; the number of calcium nodules in group A was higher than that in group B (P ﹤ 0.05). ConclusionThe expression of BMP-2 and osteogenic effect of BMSCs transfected by Ad-BMP-2-IRES-HIF-1αmu (double genes in single carrier) are higher than those of BMSCs transfected by Ad-CMV-BMP-2-IRES-hrGFP-1 (one gene in single carrier).
Objective To explore the effects of bone marrow mesenchymal stem cells (BMSCs) transfected with adenovirus hepatocyte growth factor (Ad-HGF) on wound repair in diabetic rats. Methods BMSCs from male Wistar rats were isolated by density gradient centrifugation, cultured, and transfected with Ad-HGF. The multi pl icity of infection was 100. Diabetic models were establ ished in 20 female Wistar rats by diets in high fat and sugar plus intraperitoneal injection ofstreptozotocin (30 mg/kg). Then 2 full-thickness skin wounds (approximately 1.5 cm in diameter) were made on the dorsum. The rats were randomly divided into 4 groups (n=5 rats). After wounding, the 0.3 mL suspensions of BMSCs (group A), Ad- HGF (group B), BMSCs transfected with Ad-HGF (group C), and PBS (group D) were injected directly into the derma of wounds. The transverse diameter and longitudinal diameter of wound were measured at 21 days after treatment. At 7 days and 28 days after treatment, HE staining was performed to evaluate wound heal ing. The contents of hydroxyprol ine and advanced glycosylation end products (AGEs) in the wounds were measured by enzyme l inked immunosorbent assay and fluorospectrophotometer, respectively, at 3, 7, 14, and 28 days after treatment. Results At 21 days after treatment, the wounds almost healed in group C, and the transverse diameter and longitudinal diameter were 0 and (0.110 ± 0.024) cm, respectively. But the wounds healed partially in groups A, B, and D, and the transverse diameter and longitudinal diameter were (0.470 ± 0.051) cm and (0.590 ± 0.041) cm, (0.390 ± 0.042) cm and (0.480 ± 0.032) cm, and (0.700 ± 0.068) cm and (0.820 ± 0.068) cm, respectively. There were significant differences in wound heal ing between group C and groups A, B, and D (P lt; 0.05). The wound heal ing time of group C [(20.5 ± 1.9) days] was significantly shorter (P lt; 0.05) than those of groups A, B, and D [(28.3 ± 1.9), (25.9 ± 2.3), and (36.6 ± 5.1) days]. At 7 days, the HE staining showed that evident epidermis transportation, collagen formation, and leukocytes infiltration were observed in group C. At 28 days, the HE staining showed that the epidermis in group C was significantly thinner and more regular than those in other groups, and the decreased collagen and many small vessels were observed in group C. The content of hydroxyprol ine in group C was higher than those in groups A, B, and D at 7 days and 14 days (P lt; 0.05). The contents of AGEs in group C was lower than those in groups A, B, and D at 14 days and 28 days (P lt; 0.05). Conclusion Transplantation of BMSCs transfected with Ad-HGF can accelerate the wounds repair in diabetic rats.
ObjectiveTo clone full-length cDNA of rat galectin-9 and construct recombinant adenovirus granule containing rat galectin-9 gene. MethodsThe galectin-9 gene was amplified by RT-PCR from rat liver tissue and inserted orientationally into plasmid pDC316-GFP digested by restriction endonucleases NotⅠ and HindⅢ. The recombinant pDC316-GFP-galectin-9 shuttle plasmid was identified by PCR, restriction endonuclease digestion and sequencing, and then co-transfected with rescue plasmid pBHGlox△E1.3Cre into HEK-293 cells by liposome reagent. Recombinant adenovirus vector containing rat galectin-9 gene (Ad5-galectin-9) was generated by sitespecific recombination and confirmed by PCR, and then Ad5-galectin-9 was propagated in HEK-293 cells and purified. The infectious titer of viral stock was determined by TCID50 assay. ResultsConstruction of pDC316-GFP-galectin-9 shuttle plasmid was confirmed to be correct by PCR, restriction endonuclease digestion and sequencing. Construction of recombinant adenovirus Ad5-galectin-9 was confirmed to be correct by PCR. The infective titer of Ad5-galectin-9 was 1.4×109 U/ml. ConclusionRecombinant adenovirus vector containing rat galectin-9 gene (Ad5-galectin-9) is successfully constructed, which provides the foundation of further research on the function of galectin-9 gene.
Objective To observe effects of the direct impaction onthe cell survival and the bone formation of the tissue engineered bone modified by the adenovirus mediated human bone morphogenetic protein 2 (Adv-hBMP2) gene and to verify the feasibility of the impacted grafting with it. Methods The marrow stromal cells (MSCs) were separated from the canine bone marrow and were cultured. MSCs were transfected with the Adv-hBMP2 gene and combined with the freeze-dried cancellous bone (FDB) to form the tissue engineered bone. Four days after the combination, the tissue engineered bone was impacted in a simulated impactor in vitro and implanted in the mouse. The cell survivals were evaluated with SEM 1 and 4 days after the combination, immediately after the impaction, and 1 and 4 days after the impaction, respectively. The bone formation and the allograft absorption were histologically evaluated respectively. Results There were multiple layers of the cells and much collagen on FDB before the impaction. Immediately after the impaction, most of the cells on the direct contact area disappearedand there was much debris on the section. Some of the cells died and separatedfrom the surface of FDB at 1 day, the number of the cells decreased but the collagen increased on the surface at 4 days. Histologically, only the fibrous tissue was found in FDB without the cells, the bone formation on FDB was even in distribution and mass in appearance before the impaction, but declined and was mainly on the periphery after the impaction in the AdvhBMP2 modified tissue-engineered bone. Conclusion The simulated impaction can decrease the cells survival and the bone formation of the AdvhBMP-2 modified tissue-engineered bone. The survival cells still function well.It is feasible to use the tissue engineered bone in the impaction graft.
Objective To construct recombinant adenovirus vector containing human transforming growth factor beta 3 (TGF-β3), which was transfected into marrow mesenchymal stem cells(MSCs) and to observe its expression. Methods The cDNA TGF-β3 was intergraded into the shuttle vector of pAdTrack-CMV and recombinated with adenovirus skeleton vector pAdEasy-1 by homologous recombination. Then the product was transfected into package cell HEK293 by lipofedtamine and the recombinant adenovirus expressing the TGF-β3genewas generated. The rabbit’s MSCs were isolated, cultivated, purified, and then transfected with recombinant adenovirus containing the TGF-β3 gene. The green fluorescence protein expression was observed after 10 days, and the TGF-β3 expression was observed in MSCs transfected by recombinated adenovirus with TGF-β3 gene after 4 days. Results PCR showed that TGF-β3 cDNA was inserted into the recombinantadenoviral plasmid. The recombinant virus vectors with TGF-β3 gene were collected by the packaging HEK293 cells. The fusion rate of MSCs was 70%-80% with an intensive adhesion and uninform shape after the cultured 10th day. Fluorescent microscopy and immunocytochemistry demonstrated that TGF-β3 was expressed in MSCs. Conclusion Successful construction of human TGF-β3 recombinant adenovirus and its expression in MSCs provide a basis of research for the gene therapy of wound healing.
Objective To evaluate the osteogenic potential of human bone marrow mesenchymal stem cells (MSCs) transferred with human bone morphogenetic protein 2(BMP 2) gene by adenovirus. Methods The MSCs were isolated from human bone marrow and cultured in vitro. They were divided into 3 groups: Adv hBMP 2 transduced group; Adv βgal transduced group; untransduced group. Western immunoblot analysis, alkaline phosphatase(ALP) staining, Von Kossa staining, and a quantitative ALP activity assay were performed. Nine unde mice received injection into a thigh muscle to test the osteoinductivity of the three types of cells. Results In the Adv-hBMP-2 transprotein; most MSCs were stained positively for ALP activity 9 day after transduction; the MSCs reached the peak of ALP activity 12 day after transduction; the calcified nodes formed 21 days after transduction. The ectopic bones formed in the thigh muscles of the nude mice. Little bone formation was observed in the other groups 4 weeks after cell injection. Conclusion Adenovirus mediated hBMP-2 gene transfection can induce osteogenesis of human bone marrow mesenchymal stem cells.
Objective To study efficiency and security of the recombinant adenoviralmediated gene transfer to the donor heart during the heart transplantation. Methods A total of 140 healthy male Wistar rats,aged 10 weeks, weighing 200250 g, were equally divided into the donor group and the recipient group, and then 70 rats in the recipient group were randomly andequally divided into 2 subgroups: the gene transfer group and the control group. The rat model of heterotopic heart transplantation(Abdomen)was developed, the donor hearts were removed and their coronary arteries were perfused with 800 μlof the recombinant adenoviral vectors encoding the β-galactosidase gene（Ad-LacZ）. The grafts were stored in the 4℃ cold saline solution for 30 minutes, and then the syngeneic transplant was performed. In the control group, saline of tales doses was perfused. The donor hearts were harvested at 3, 5, 7, 14, and 28days (n=7)after transplantation, and the β-galactosidase activity was assessed by the X-gal staining. At 28 days the major organs of the recipients were tested by the histopathological analysis and the polymerase chain reaction of the adenoviral E1A sequences. Results The successful gene transfer of the βgalactosidase gene was demonstrated in the adenovirus-perfused hearts, with no staining in the control group. The gene expression reached a peak level at 3, 5 and 7 days, and the averaged numbers of the total βgalactosidase positive staining cells per slice were 66.4±23.1, 91.3±32.4 and 68.7±22.7, respectively, with no significant difference between the groups (Pgt;0.05). At 14 days the gene expression gradually declined (32.1±13.9), and the significant difference was found when compared with that at 3, 5 and 7 days (Plt;0.05). At 28 days the cells positive for β-galactosidase were sparse (3.9±3.4), and the gene transfer was significantly less efficient compared with that at 3, 5, 7 and 14 days (Plt;0.05). The major organs of the recipients were not affected seriously at 28 days. No virus spread to other organs in this experimental protocol. Conclusion The ex vivo adenoviralmediated gene transfer intracoronarily to the donor heart during the heart transplantation is feasible and safe.
Objective To replace dysfunctional Fas gene and reconstruct the blocked Fas signal by using two kinds of prepared recombinantAdenovirus which have human Fas gene. Methods After the keloids derived from fibroblasts were infected by the Adenovicus, the expressions of Fas protein before the exposure and after the exposure was compared. Then the function of the newly produced Fas protein was detected. Results The highly improve expression of Fas protein in the infected keloid derived fibroblasts was detected. Obvious apoptosis was also detected in the infected keloid derived from fibroblasts under the condition of exposing to FasMcab. Conclusion ①The recombinant Adenovirus with Fas gene can transfect the Fas gene into keloidderived fibroblasts and highly improved the expression of Fas protein. The newly expressed Fas gene can reconstruct the blocked Fas signal. ②Ad-Fas(B) has better therapeutic effect in vitro gene therapy. ③ The correlation between keloid and Fas gene was further proved and it may pave the way for further gene therapy in keloid .
