Objective To evaluate the host immune reaction against adenovirus mediated human bone morphogenetic protein 2 (Adv-hBMP-2) gene therapy in repairof tibial defects. Methods Twelve goats were made 2.1 cm segmental defects in he tibial diaphysis and divided into 2 groups. AdvhBMP2 transfected marrow mesenchymal stem cells(MSCs) and untransfected MSCs were implanted into the defect sites of transfected group(n=7) and untransfected group (n=5), respectively. The defect repair was observed by X-ray films after 4, 8, 16 and 24 weeks of transplantation and cellular and humoral immune reactions to adenovirus were assayed before implantation and after implantation. Results More bony callus was found in the bone defects of transfected group. The healing rates were 6/7 in transfected group and 2/5 in untransfected group, respectively at 24 weeks after implantation. The mixed culture of lymphocytes and MSCs showed that the lymphocytes stimulation indexes (SI) increased 14 days after implantation, and there was significant difference between the transfected group (4.213±1.278) and the untransfected group(－0.310±0.147，Plt;0.05); SI decreased after 28 days, but there was no significant difference between the transfected group (2.544±0.957) and the untransfected group (3.104±0.644，Pgt;0.05). After 14, 28, 49, and 120 days of treatment, the titer values of neutralizing antibody against Adv-hBMP-2 (log0.1) were 2.359±0226, 2.297±0.200, 2.214±0.215 and 2.297±0.210 in transfected group, and -0.175±0.335, -0.419±0.171, 0±0.171 and 0.874±0.524 in untransfected group, being significant differences betweentwo groups(Plt;0.05). Conclusion Adenovirus mediated BMP-2gene therapy can cause cellular and humoral immune reactions against adenovirus, which can eliminate the influence of adenoviral genes and proteins within a certain period.
Objective To explore the effects of overexpression of human tissue inhibitors of metalloproteinase-1 (hTIMP-1) on proliferation of human liver cancer cell line HepG2 in vitro. Methods A recombinant adenoviral vector containing full-length cDNA of hTIMP-1 was generated and transfected into HepG2. The viral titer was checked by measuring GFP, and the expression of hTIMP-1 in vitro was detected by the techniques of Western blot and semi-quantitative RT-PCR. The ultrastructure was observed by transmission electron microscope and the effects of overexpression of hTIMP-1 on proliferation of HepG2 in vitro was analyzed by MTT assay and growth curve. Results The resultant AdhTIMP-1 was successfully constructed and the expression of hTIMP-1 was detected by Western blot and RT-PCR. The growth and proliferation of HepG2, which had been transfected with AdhTIMP-1, was significantly inhibited. Conclusion The proliferation of HepG2 was markedly inhibited by recombinant adenovirus-mediated overexpression of hTIMP-1, which may pave the way for further application in liver gene therapy.
Objective To review the current concepts of gene therapy approachesmediated by adenovirus vectors for bone trauma and bone disease. Methods The recent literature concerned gene therapy mediated by adenovirus vectors was reviewed, which provides new insights into the treatments of bone trauma and bone disease. Results Adenovirus vectors was efficient, achieved high expression after transduction, and could transfer genes to both replicating and nonreplicating cells, such as osteoblasts, osteoclasts, fibroblasts, chondrocytes, bone marrow stromal cells, etc. Gene therapy mediated by adenovirus vectors achieved affirmative results in enhancing bone union and in curing bone diseases, such as osteoporosis and rheumatoid arthritis. Conclusion Gene therapy mediatedby adenovirus offers an exciting avenue for treatment of bone trauma and bone diseases.
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 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.
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.
ObjectiveTo construct recombinant adenovirus expressing nerve growth factor (NGF) and myelin associated glycoprotein (MAG) (Ad-NGF-MAG) and to investigate its effect on repair and regeneration of sciatic nerve injury in rats. MethodsNGF and MAG gene sequences were cloned into shuttle plasmid pCA13 of adenovirus type 5. After packed in HEK293 cells, the recombinant Ad-NGF-MAG underwent sequence and identification. Thirty-two male Sprague Dawley rats were randomly divided into 4 groups (n=8): control group (normal control), adenovirus vector group (Ad group), Ad-NGF group, and Ad-NGF-MAG group. The sciatic nerve injury model was established by transection of the right sciatic nerve; then, the empty adenovirus vector, Ad-NGF, and Ad-NGF-MAG were injected into the gastrocnemius muscle of the affected limb at a dose of 1×108 PFU every other day for 3 times in Ad group, AdNGF group, and Ad-NGF-MAG group, respectively. The right sciatic nerve was exposed only, and then the incision was closed in the control group. The sciatic nerve function index (SFI) was measured, and neuro-electrophysiology was observed; mRNA and protein expressions of NGF and MAG were detected by RT-PCR and Western blot; and histological examination was performed at 31 days after operation. ResultsRecombinant adenovirus vectors of Ad-NGF and Ad-NGF-MAG were constructed successfully. All rats survived and incision healed by first intension. The SFI, nerve conduction velocity, evoked potential amplitude, and latent period of Ad-NGF-MAG group were significantly better than those of Ad group and Ad-NGF group (P < 0.05). MAG mRNA and protein expressions of Ad-NGF-MAG group were the highest in all the groups (P < 0.05). The expressions of NGF mRNA and protein increased in Ad-NGF group and AdNGF-MAG group when compared with control group and Ad group (P < 0.05). Histological examination showed that the nerve had good continuity in control group; nerve fibers disarranged in Ad group; neurons connections formed in some nerve fibers of Ad-NGF group, but nerve fibers arrange disorderly; and the growth of the nerve were ordered and wellstructured in Ad-NGF-MAG group. ConclusionAd-NGF-MAG can effectively promote the growth of the nerve and inhibit the form of abnormal branches, facilitating the repair of sciatic nerve injury in rats.
Objective To evaluate the suitability of the biodegradable microsphere encapsulation of adenovirus as a targeting vector for gene therapy of hepatocellular carcinoma. Methods Encapsulate the recombinant adenovirus in PLG 〔poly (lactic/glycolic)〕 copolymer by the solution evaporation method, the release test and the bioactivity of viruses incorporated in vitro were studied. Results More than 19.3% of adenovirus was encapsulated in PLG microspheres. The release test shows that the adenovirus was released for more than 200 h, 50% were shed within the first 100 h, and their activity was retained. Conclusion Recombinant adenovirus can be formulated in a polymer preparation of PLG with retention of bioactivity. It may be a valuable vector for the gene therapy of liver cancer.
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 .
ObjectiveTo investigate the proliferation and apoptosis effects of adenovirus-mediated interleukin-24 (Ad-IL-24) gene on Karpas299 cells in vitro. MethodsThe Karpas299 cells were divided into blank control group, Ad-IL-24 group, and the adenovirus which carrying green fluorescent protein gene group (Ad-GFP group). Karpas299 cells of Ad-IL-24 group were infected by adding 200.0 μL Ad-IL-24, Karpas299 cells of Ad-GFP group were infected by adding 200.0 μL Ad-GFP, but Karpas299 cells of blank control group were treated by adding 200.0 μL PBS. Cells' proliferation inhibition rates of 3 groups were detected by cell counting kit (CCK-8) method at 12, 24, and 48 hours after treatment, respectively, and the cells' apoptosis rates of 3 groups were detected by flow cytometry at 48 hours after treatment. ResultsAd-IL-24 can suppress the growth of Karpas299 cells, and the inhibition rate increased over time. Compared with Ad-GFP group at the same time, the cell' proliferation inhibition rate of Ad-IL-24 group was higher at 12, 24, and 48 hours after treatment (P<0.05). In addition, the cells' apoptosis rate of Ad-IL-24 group was higher than those of Ad-GFP group and blank control group at 48 hours after treatment (P<0.05). ConclusionAd-IL-24 can suppress the growth of Karpas299 cells and induce the apoptosis of it.