Objective To construct the recombinant of hepatocellular carcinoma-targeting adenovirus containing r-Caspase-3 gene and provide the gene therapic strategy for hepatocellular carcinoma. Methods The pAdTrack-EAFP-PALB was constructed and the r-Caspase-3 gene was subcloned into the vector. The linearized shuttle plasmid was homogenously recombined with AdEasy-1 in BJ5183 cells. The candidate clone was analyzed by restriction endonuclease digestion and sequencing, and then pAdEasy-EAFP-PALB/r-Caspase-3 vector was digested with PacⅠand transfected into AD293 cells for packaging and amplifying, recombinant virus was constructed successfully. Infection titer and efficiency of recombinant virus were monitored by green fluorescent protein (GFP) expression. The expression of r-Caspase-3 in infected HepG2 cells was detected by RT-PCR and Western blot. The apoptosis of HepG2 cells was detected by SRB dyeing method. Results Shuttle vector pAdTrack-EAFP-PALB/r-Caspase-3 was correct after identification by restriction endonuclease analysis and sequencing. By PCR and PacⅠ restriction endonuclease analysis， the homologous recombinant of pAdEasy-EAFP-PALB/r-Caspase-3 was successful. The expression of GFP was observed when linearized pAdEasy-EAFP-PALB/r-Caspase-3 was transfected into AD293 cells. AD293 cells could be infected repeatedly by recombinant adenovirus. The expression of r-Caspase-3 gene on HepG2 cells was detected by RT-PCR and Western-blot methods respectively, which confirmed that the Ad-EAFP-PALB/r-Caspase-3 was constructed successfully. The specificity of Ad-EAFP-PALB/r-caspase-3 which targeting induced hepatocellular carcinoma cells was founded by SRB dyeing test. Conclusion The Recombinant of hepatocellular carcinoma-targeting adenovirus containing r-Caspase-3 gene was constructed successfully and which established the foundation of r-Caspase-3 gene therapy in future research to hepatocellular carcinoma.
Objective To construct recombinant adenovirus vector co-expressing human interleukin (hIL)-10 and green fluorescent protein (GFP) for study of the expression of genes of interest in vascular smooth muscle cells （VSMCs）. Methods hIL-10 cDNA was amplified from pUCm-T/hIL-10 cDNA using polymerase chain reaction (PCR), and cloned into shuttle plasmid pShuttle-IRES-hrGFP-1. Kanamycin resistance screeninged for recombinant plasmids, which were linealized with PmeⅠand transformed into BJ5183-AD-1 containing pAdEasy-1 by electroporation after determining the insert’s sequence correct by NotⅠ and XholⅠdigestion， sequencing and basic local alignment search tool (BLAST). Prepared recombinant adenovirus plasmids were transformed into XL10-Gold cells. Amplified plasmids were transfected to AD-293 cells for packaging after being linearized with PacⅠ. PCR was used to determine target gene; The titer of the recombinant adenovirus was measured. VSMCs were transfected by recombinant adenovirus and viewed under fluorescence microscope. hIL-10 concentration in transfected VSMCs supernant was measured by enzyme linked immune sorbent assay (ELISA). Results Recombinant shuttle plasmids contained interest gene. Recombinant adenovirus had 30 kb and 3 kb fragments after digestion with PacⅠ. PCR indicated that the recombinant adenovirus contained interest gene. The titer of recombinant adenovirus was 3×10１0 efu/ml. Transfected VSMCs had GFP expression and hIL-10 concentration in supernatant was 25 ng/106 cells. Conclusion The recombinant adenovirus co-expressing hIL-10 and GFP is successfully constructed and could effectively express in VSMCs, this lays the foundation for the gene therapy of vascular intimal hyperplasia.
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 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.
ObjectiveTo detect the expression of human transforming growth factor β1 (hTGF-β1) gene mediated by adenovirus (Ad) in hamstring tendon after anterior cruciate ligament (ACL) reconstruction in rabbits. MethodsAd-hTGF-β1 and Ad-green fluorescent protein (GFP) were diluted to 5×108 PFU/mL with DMEM. Forty-eight New Zealand white rabbits were divided into 3 groups randomly (n=16) for ACL reconstruction with hamstring tendon autograft. Hamstring tendon was cultured and transfected with Ad-hTGF-β1 (group A) and Ad-GFP (group B) for 12 hours before ACL reconstruction, and was cultured with DMEM in group C. After 12 hours of transfection, green fluorescence was observed in groups A and B under fluorescence microscopy. At 2, 4, 6, and 8 weeks after operation, the hamstring tendon was harvested to detect the mRNA and protein expressions of hTGF-β1 by real time fluorescence quantitative PCR and Western blot. ResultsGreen fluorescence was observed after 12 hours of transfection in groups A and B. TGF-β1 protein level reached (221.0±12.2) ng/mL at 12 hours in group A. The hTGF-β1 mRNA expression could be detected in group A, but it could not be detected in group B and group C. The mRNA expression levels of hTGF-β1 were 1.004±0.072 at 2 weeks, 0.785±0.038 at 4 weeks, 0.469±0.053 at 6 weeks, and 0.172±0.021 at 8 weeks in group A, showing significant difference (P<0.05). Western blot results showed weakly positive band in groups B and C; the protein expression of TGF-β1 in group A was significantly higher than that in groups B and C (P<0.05), but no significant difference was found between groups B and C P>0.05). The protein expression of TGF-β1 gradually reduced with time, showing significant difference between different time points (P<0.05). ConclusionAd-hTGF-β1 can transfect the hamstring tendon successfully, and it can effectively express for a long time after ACL reconstruction.
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 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 investigate the feasibility of rabbit synovial-derived mesenchymal stem cells (SMSCs) differentiating into fibrocartilage cells by the recombinant adenovirus vector mediated by bone morphogenetic protein 2/7 (BMP-2/7) genes in vitro. Methods SMSCs were isolated and purified from 3-month-old New Zealand white rabbits [male or female, weighing (2.1 ± 0.3) kg]; the morphology was observed; the cells were identified with immunocytological fluorescent staining, flow cytometry, and cell cycles. The adipogenic, osteogenic, and chondrogenic differentiations were detected. The recombinant plasmid of pAdTrack-BMP-2-internal ribosome entry site (IRES)-BMP-7 was constructed and then was used to infect SMSCs. The cell DNA content and the oncogenicity were tested to determine the safety. Then infected SMSCs were cultured in incomplete chondrogenic medium in vitro. Chondrogenic differentiation of infected SMSCs was detected by RT-PCR, immunofluorescent staining, and toluidine blue staining. Results SMSCs expressed surface markers of stem cells, and had multi-directional potential. The transfection efficiency of SMSCs infected by recombinant plasmid of pAdTrack-BMP-2-IRES-BMP-7 was about 70%. The safety results showed that infected SMSCs had normal double time, normal chromosome number, and normal DNA content and had no oncogenicity. At 21 days after cultured in incomplete chondrocyte medium, RT-PCR results showed SMSCs had increased expressions of collegan type I and collegan type II, particularly collegan type II; the expressions of RhoA and Sox-9 increased obviously. Immunofluorescent staining and toluidine blue staining showed differentiation of SMSCs into fibrocartilage cells. Conclusion It is safe to use pAdTrack-BMP-2-IRES-BMP-7 for infecting SMSCs. SMSCs infected by pAdTrack-BMP-2-IRES-BMP-7 can differentiate into fibrocartilage cells spontaneously in vitro.
Objective To construct gene silence adenovirus vector targeting both transglutaminase 2 （TG2） and Mer receptor tyrosine kinase （Mertk） synchronously and detect the gene silence function of it. Methods The interfering plasmids targeting TG2 protein and Mertk protein were constructed firstly， then the H1 promoter and RNA interfering （RNAi） sequence were cut and ligated to pAdTrack for constructing pAdTrack/TG2/Mertk. The pAdTrack/TG2/Mertk was transfected into BJ5183 bacterial cells which contained pAdEasy-1， then the plasmid was detected by enzyme digestion after recovery. Adenovirus were harvested after that pAdTrack/TG2/Mertk was infected into HEK293 cells. The virus titer was measured after repeated amplification. The RAW264.7 cells were infected by pAdTrack/TG2/Mertk， pAdTrack/TG2， pAdTrack/Mertk， and pAdTrack/green fluorescent protein （GFP）， respectively. Then the expression levels of TG2 protein and Mertk protein of mouse macrophages were detected by Western blot after infection. Results The virus titer of pAdTrack/TG2/Mertk plasmid was 6.13×1010GFU/mL. The pAdTrack/TG2/Mertk plasmid which contained 2 promoters and 2 RNAi sequences was identified successfully by enzyme digestion. Compared with pAdTrack/GFP group and pAdTrack/Mertk group （there was no significant differece between the 2 groups）， the expression levels of TG2 protein of mouse macrophages which infected with pAdTrack/TG2/Mertk or pAdTrack/TG2 decreased obviously （P＜0.01）， but there was no significant difference between the later 2 groups. Compared with pAdTrack/GFP group and pAdTrack/TG2 group （there was no significant difference between the 2 groups）， the expression levels of Mertk protein of mouse macrophages which infected with pAdTrack/TG2/Mertk or pAdTrack/Mertk decreased obviously too （P＜0.01）， but there was no significant difference between the later 2 groups. Conclusion Gene silence adenovirus vector plasmid targeting both TG2 and Mertk synchronously is constructed successfully， and the pAdTrack/TG2/Mertk can reduce the expressions of TG2 protein and Mertk protein of mouse macrophages obviously.
ObjectiveTo investigate the effect of hamstring tendon transfected with adenovirus-mediated transforming growth factor β1 (AdTGF-β1) genes on the histomorphology of tendon-bone interface healing after anterior cruciate ligament (ACL) reconstruction in rabbits. MethodsAdTGF-β1 and AdGFP were diluted to 5×108 PFU/mL with DMEM. Forty-eight New Zealand white rabbits were divided into 3 groups randomly (n=16), weighing 1.6-2.5 kg for ACL reconstruction with hamstring tendon autograft. Hamstring tendon was cultured and transfected with AdTGF-β1 (group A) and AdGFP (group B) for 12 hours before ACL reconstruction, and was cultured with DMEM in group C. After 12 hours of transfection, the expression of green fluorescence was observed in groups A and B under fluorescence microscopy; TGF-β1 protein level was detected by ELISA in group A. At 2, 4, 8, and 12 weeks after operation, the specimens were harvested for HE and Masson staining; the number of fibroblasts was counted, and the Buark grading was used to evaluate tendon-bone interface healing. ResultsGreen fluorescence was observed after 12 hours of transfection in groups A and B. TGF-β1 protein level reached (221.0±12.2) ng/mL at 12 hours in group A. The histological observation showed that few fibroblasts and collagen fibers were found, and Sharpey fibers appeared in group A; regular Sharpey fibers were seen in the interface, and integrity interface in some areas at 12 weeks. But fibroblasts of groups B and C were less than those of group A, with loose tendon-bone interface; no integrity interface was observed at 12 weeks. The number of fibroblasts and Buark grading of group A were significantly higher than those of groups B and C (P<0.05), but no significant difference was found between groups B and C (P>0.05). ConclusionHamstring tendon transfected with AdTGF-β1 gene can promote the healing of tendon-bone interface after ACL reconstruction.