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 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 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 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.
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.
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.
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 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 expression of FLIP in the lung of rats and the protective effect in development of acute lung injury( ALI) with the adenovirus vector carrying FLIP gene( Ad-FLIP)inhaled. Methods Forty-eight rats were randomly divided into four groups, with 12 rats in each gruop. In treatment group, ALI rats model was eatablished by LPS intraperitoneal injection and then inhaled Ad-FLIP vector. In prevention group, the animals were infected with Ad-FLIP vector before ALI model wasestablished. Two control groups of treatment and prevention received Ad-EGFP vectors respectively.Pathological changes of lung were observed under light microscope. Wet/dry weight ( W/D) of lung lobes and lung permeability index( LPI) were also measured. The mRNA and protein expressions of FLIP in lungwere investigated by RT-PCR and immunohistochemistry, respectively. Results Lung histopathological changes were alleviated, the index of W/D and LPI were significantly lower, the expressions of FILP mRNA and protein in the lung were elevated both in the treatment group and prevention group compared to thecontrol groups ( all P lt;0. 01) . Conclusion Ad-FLIP transfection can up-regulate the expression of FLIP in lung of rats, and might protect respiratory membrane and lessen pulmonary edema to prevent the development of ALI.
ObjectiveTo construct a transgenic cell sheet of cartilage-derived morphogenetic protein 1 (CDMP-1) by adenovirus vector in vitro and to identify its biological activity.
MethodsThe bone mesenchymal stem cells (BMSCs) were isolated from bone marrow of 1-month-old rabbit, and cultured in vitro. The 3rd-6th generation of BMSCs were used for experiment. The experiment was divided into 3 groups:BMSCs transfected by adenovirus (Ad)-cytomegalovirus (CMV)-human CDMP1 (hCDMP1)-internal ribosome entry site (IRES)-enhanced green fluorescent protein (EGFP) in group A, BMSCs transfected by Ad-CMV-EGFP in group B, and untransfected BMSCs in group C. The expression of green fluorescence was observed in 3 groups under fluorescent inverted microscope. MTT assay was used to detect the proliferation of the cells. The cell sheet was obtained by means of temperature-responsive culture dish for 14 days. The morphological and HE staining observations of the cell sheet were carried out. RT-PCR and Western blot were used to detect the expressions of hCDMP1 and collagen type II at gene and protein levels, while alcian blue staining was used to detect the expression of glycosaminoglycans (GAG).
ResultsBright green fluorescence was observed in transfected cells at 72 hours under fluorescent inverted microscope, and the transfection efficiency was up to 90%. MTT assay showed approximate S-shaped growth curves in 3 groups, showing no significant difference in the absorbance (A) value among 3 groups within 9 days (P>0.05). The three-dimensional cell sheets were successfully harvested in vitro. The RT-PCR and Western blot showed that there were positive expressions of hCDMP1 and collagen type II in group A and negative expression in other 2 groups. HE staining and alcian blue staining showed that there were rich fibrous tissues, mass extracellular matrix, and dark blue metachromatic granules in group A, but there was less fibrous tissues and no specific blue metachromatic granules in other 2 groups; and the positive expression area was significantly lower and gray scale of GAG was significantly higher in group A than that in groups B and C (P<0.05).
ConclusionA transgenic cell sheet of exogenous recombinant hCDMP1 by adenovirus vector can express collagen type II and GAG, so it has chondrogenic capacity. This technology that overcomes limitations in traditional tissue engineering, such as low cell-attachment efficiency and inflammatory reaction, may be a new tissue engineering approach for hard tissue reconstruction and is hopeful to build a large density of tissue engineered cartilage.
