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 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 investigate the differentiation of theadipose-derived adult stem cell (ADASC) induced by the recombinant adenovirus’s containing fibers derived from B-group serotype 35 (rAd5/F35)mediated human bone morphogenetic protein 7 (hBMP-7) gene and to explore a new cell sourcefor the bone tissue engineering. Methods The hBMP-7 gene wasamplified with the pcDNA1.1/AMP-hBMP-7 plasmid as a formwork. After the purification, the gene fragment was cloned into the pDC316 carrier for the recombination of the plasmid of pDC316-hBMP-7. The 293 cells were cotransfected by the skeleton plasmid of pBHG-fiber5/35 and the shuttle plasmid of pDC316-hBMP-7, and the recombinant plasmid of Ad5/F35-hBMP-7 was obtained; the recombinant plasmid of Ad5/F35enhancd green fluorescent protein(EGFP) was obtained by the similar method. The rat ADASCs were cultured and transfected by the Ad5/F35-hBMP-7plasmid and the Ad5/F35-EGFP plasmid, respectively; the remaining untransfected ADASC were used as the controls. The morphology and the growth pattern of the transfected cells were evaluated. The transcription and the expression of the transfected genes and the steogenic phenotypes such as calcium nodules and osteocalcin were evaluated by ELISA. Results The identification of PCR and enzyme cutting showed that the construction of the recombinant Ad5/F35-hBMP-7 plasmid could be confirmed. The transfection rate of the ADASC by the Ad5/F35-EGFP plasmid was determined to be greater than 90%. The hBMP-7 gene in thetransfected ADASC could express the corresponding protein, and the formation ofthe calcium nodules could be found in the induced group. The electron microscopy showed that there was a calcium element in the cytoplasm, the alkaline phosphatase result was positive, and the expression of osteocalcin was increased. Conclusion The rAd5/F35-hBMP-7 gene can promote the differentiation of the adiposederived adult stem cells to the osteoblasts in the bone tissue engineering.
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 investigate the effect of Adenovirus-mediated averse vascular endothelial growth factor165（Ad-aVEGF165）on the growth of human melanoma cells(A375) in vivo and in vitro.Methods In vitro,the 100 multiplicity of infection of Aadenovirus-mediated green fluorescent protein（Ad-GFP）and Ad-aVEGF165 were transfected into human endothelium cell of vessel 304（ECV 304） and A 375. ECV 304 cells were divided into 3 groups: A 375 group, AdGFP group and AdaVEGF 165group. A375cells were also divided into 3 groups:1640 group, Ad-GFP group and AdaVEGF165 group. Their effects were analyzed by proliferation assay, cell cycle, and VEGF expression. In vivo,A375cells were injected into the axilla of the nude mouse. When the tumor formed, they were transplanted into another 15 mice. After treatment, the tumor was excised for naked eye observation, HE observation and microvascular density(MVD) counting. Results The cell supernatant fluid of A 375 group and AdGFP group could stimulate ECV304 cell growth，butthat of AdaVEGF165 group could inhibit the growth of ECV304 cell.All the A375cells in 3 groups had the proliferation trend, showing no statistically significant difference（Pgt;0.05）. ECV 304 cell proliferation index(PI) in Ad-aVEGF165group reduced（Plt;0.05）. There was no statistically significant difference（Pgt;0.05） in the PI of A 375 cell. The A 375cell integral optical densities were 234.41±13.8 in 1640 group， 222.73±3.67 in AdGFP group and 180.84±6.34 in Ad-aVEGF165group. The tumor volume in Ad-aVEGF165 group was smaller than that in Ad-GFP group and PBS group at 2 weeks after operation, the trend became much obvious with the time delay. AdaVEGF165 brought to much tissue necrosis under HE stain. The MVD of PBS group, Ad-GFP group and Ad-aVEGF165group were 65 10/view,52±11/view and 30±6/view, respectively. Conclusion In Vitro, Ad-VEGF 165gene could inhibited ECV304 cells’ growth by weakening VEGF expression of A 375cells. In vivo, Ad-aVEGF 165could inhibit the growth of human melanoma from blockinmicrovascular.
Objective To research the transfer of adenovirus human bone morphogenetic protein 4 (Ad-hBMP-4) to human degenerative lumbar intervertebral disc cells in vitro and analyze its effect on the proteoglycan, collagen type II, and Sox9 of intervertebral disc cells. Methods Identified Ad-hBMP-4 was amplified and detected. Degenerative lumbar intervertebral disc cells were aspirated from the degenerative lumbar intervertebral disc of patients with Modic III level disc protrusion (aged, 27-50 years). The expressing position of collagen type II was identified in the intervertebral disc cells through the laser confocal microscope. The intervertebral disc cells at passage 1 were transfected with Ad-hBMP-4 as experimental group. After 3 and 6 days of transfection, RT-PCR was used to detect the mRNA expressions of proteoglycan, collagen type II, and Sox9, and Western blot to detect the expressions of proteoglycan and collagen type II proteins. Non-transfected cells at passage 1 served as control group. Results The virus titer of Ad-hBMP-4 was 5 × 106 PFU/mL. No morphological changes in the cells after transfection by Ad-hBMP-4. Collagen type II mainly expressed in the cell cytoplasm. The mRNA expressions of the proteoglycan, collagen type II, and Sox9 in experimental group at 3 and 6 days after transfection were significantly higher than those in control group by RT-PCR (P lt; 0.05), and the expressions of proteoglycan and collagen type II proteins were significantly higher than those in contorl group by Western blot (P lt; 0.05). There were significant differences between 3 days and 6 days in experimental group (P lt; 0.05). Conclusion Ad-hBMP-4 could transfect human degenerative lumbar intervertebral cells with high efficiency and promote collagen type II, proteoglycan, and Sox9 expressions. hBMP-4 may play an important role in the repair process during early disc degeneration.
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 investigate the effect of TIMP-2 gene that was transfected by adenovirus on extracellular matrix of abdominal aortic through assessing the changes of morphology and histopathology of the rat models with abdominal aortic aneurysm. Methods The rat models with abdominal aortic aneurysm were constructed by intraluminally perfusing porcine pancreatic elastase. Twenty-four SD rats with aneurysm were then randomly divided into 3 groups: AdTIMP-2 group (perfused locally with solution of TIMP-2 gene transfected by adenovirus vector to abdominal aorta), AdCMV group (transfected by non-viral vector), and PBS group. After 14 days, the concentrations of elastin and collagen that were collected from the samples of aortic wall were measured by image analysis system and the fixed aortic tissues were examined by light microscopy and some other specific staining methods. Results None of abdominal aortic aneurysm developed in TIMP-2 gene transfected group, with significantly higher rates of developed aneurysm in the other groups (P＜0.01). The diameters of arteries on day 14 in the AdTIMP-2 group were (2.33±0.06) mm, which were significantly smaller than those in the AdCMV group 〔（3.52±0.11） mm〕 and PBS group 〔（3.43±0.09） mm〕. The elastic fibers and collagenous fibers were preserved with more integrity in AdTIMP-2 group and inflammation cells that were observed in adventitia of artery were also less than those of the other groups. Conclusion TIMP-2 gene transfected by adenovirus vector could restore the degradation of extracellular matrix that was aroused by elastase and could block the formation of abdominal aortic aneurysm, which may provide a new strategy for the treatment of abdominal aortic aneurysm.
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 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.