Objective To construct AWP1 (associated with protein kinase C related kinase 1) recombinant adenovirus as the tool of transferring the gene and investigate its expression and localization in human vascular endothelial cell ECV304. Methods Cloned AWP1 cDNA was inserted into the multiply clone sites (MCS) of plasmid pcDNA3 for adding flag tag, and the flag-AWP1 gene was subcloned into shuttle vector pAdTrack-CMV. After identified with restrictional enzymes, plasmid pAdTrack-flag-AWP1 was linearized by digestion with restriction endonuclease PmeⅠ, and subsequently cotransformed into E.coli BJ5183 cells with adenoviral backbone plasmid pAdEasy-1 to make homologous recombination. After linearized by PacⅠ, the homologous recombinant adenovirus plasmid transfected into 293 cells with Lipofectamine to pack recombinant adenovirus. After PCR assay of recombinant adenovirus granules, recombinant adenoviruses infected 293 cells repeatedly for obtaining the high-level adenoviruses solution. And then, the recombinant adenoviruses infected human ECV304 cells for observing the expression and localization of AWP1 under laser scanning confocal microscope (LSCM). Results PCR assay showed that recombinant adenovirus Ad-flag-AWP1 was obtained successfully; and ECV304 cells were infected high-efficiently by the homologous recombinant virus. Then, it was observed that flag-AWP1 protein expressed in ECV304 cells and distributed in the leading edges of the cell membrane. Conclusion The vectors of flag-AWP1 recombinant adenovirus are constructed, and the localization of AWP1 protein in ECV304 cells might show that AWP1 may be a potential role on the cell signal transduction.
【Abstract】Objective To construct a recombinant adenoviral vector carrying antisense matrix metalloproteinase2 (MMP2) for use in the gene therapy to inhibit the invasiveness and migratory capacity of hepatocellular carcinoma (HCC) cell line HepG2 in vitro and in vivo models. Methods Total RNA was extracted from HCC, and then a 500 bp fragment at the 5′ end of human MMP2 cDNA was synthesized by polymerase chain reaction (PCR) and was reversely inserted into the multiclone site (MCS) of the shuttle plasmid pAdTrack-CMV,with the resultant plasmid and the backbone plasmid pAdEasy-1,the homologous recombination took place in the E.coli BJ5183 and the recombinant adenoviral plasmid carrying the antisense MMP2 gene was constructed and generated. The adenoviruses(Ad-MMP2AS) were packaged and amplified in the HEK 293 cells.Then the viral titer was checked by GFP. Results The recombinant adenovirus vector carrying antisense MMP2 was constructed successfully, the b green fluorescence was observed in HEK 293 cells under a fluorescence microscopy. The viral titer was 1×108/ml. Conclusion The recombinant adenovirus Ad-MMP2AS constructed by us could introduce the antisense MMP2 into HepG2 effectively,which would provide experimental basis for reversing the overexpression of MMP2 in HCC and for inhibiting the invasiveness and migratory capacity of HepG2 in vitro and in vivo models.
ObjectiveTo construct the recombinant adenovirus vector carrying antisense multidrug resistanceassociated protein (MRP) and transfect the human drugresistant hepatocellular carcinoma cell line(SMMC7721/ADM). MethodsThe fragment of MRP gene encoding 5′region was cloned reversely into the shuttle plasmid pAdTrackCMV, with the resultant plasmid and the backbone plasmid pAdEasy1,the homologous recombination took place in the bacteria and the recombinant adenoviral plasmid was generated. The adenoviruses were packaged and amplified in 293 cells. Then the cell line of SMMC7721/ADM was transfected with the resultant adenoviruses.ResultsThe recombinant adenovirus vector carrying antisense MRP was constructed successfully. The viral titer was 2.5×109 efu/ml, and more than 90% SMMC7721/ADM cells could be transfected when the multiplicity of infection（MOI） was 100. ConclusionThe recombinant adenovirus vector constructed by us could introduce the antisense MRP into the human drugresistant hepatocellular cell line effectively, which would provide experimental basis for the mechanisms and reversal methods of the multidrug resistance in human hepatocellular carcinoma.
Objective To determine the transfection efficiency of recombinant adenovirus to endothelial progenitor cells(EPCs) and provide the base of lung cancer therapy by transfecting human herpes simplex virusthymidine kinase（HSV-TK） gene to EPCs. Methods Admove recombinant adenovirus 5F35(AD5F35) which transfected with βgalactosidase(AD5F35LacZ) to the 24 well plate cultivated with EPCs and transfect the EPCs. Stain the EPCs with LacZ kit and calculate the transfection efficiency. Results The blue stain cells were cells transfected successfully with AD5F35LacZ under the optical microscope. The transfection efficiencies of adenovirus to EPCs were different under the premise of the different multiplicity of infection(MOI). In a certain range, the transfection efficiencies rise with the MOI rise. When MOI was 400,the proportion of blue stain cell is the highest, which was 98.38%±1.25%. Conclusion Recombinant adenovirus can transfect EPCs successfully. The transfection efficiencies rise with the MOI rise. When the MOI is 400,the transfection efficiency is the highest.
Objective To transfect bone marrow mesenchymal stem cells (BMSCs) of rats by recombinant adenovirus Ad-human matrix metalloproteinase 1 (hMMP-1) in vitro so as to lay the experimental foundation for the treatment of liver fibrosis with a combination of BMSCs and hMMP-1 gene transplantation. Methods BMSCs were isolated from bone marrow of 2-3 weeks old Sprague Dawley rats by whole bone marrow adherence method and identified, then transfected by recombinant adenovirus Ad-hMMP-1 carrying enhanced green fluorescent protein (EGFP) marker in vitro. The green fluorescent expression was observed by fluorescence microscope and the transfection efficiency was detected by flow cytometry to determine the optimum multiplicity of infection (MOI). BMSCs at passage 3 were divided into 3 groups: untransfected BMSCs group (group A), Ad-EGFP transfected BMSCs group (group B), and Ad-hMMP-1-EGFP transfected BMSCs group (group C); the gene and intracellular protein of hMMP-1 were detected by RT-PCR and Western blot; the ELISA assay was used to detect the supernatant protein expression, and the hMMP-1 activity was measured by fluorescent quantification kit. Results The green fluorescent was observed in BMSCs transfected by recombinant adenovirus at 24 hours after transfection; the fluorescence intensity was highest at 72 hours; and the optimum MOI was 200. The cells of 3 groups entered the logarithmic growth phase on the 3rd day and reached plateau phase on the 6th day by MTT assay; no significant difference was found in the cell proliferation rate among 3 groups (P gt; 0.05). RT-PCR, Western blot, and ELISA assay showed high expressions of the hMMP-1 gene and protein in group C, but no expression in groups A and B. The hMMP-1 activity was 1.24 nmol/(mg · min) in group C, but hMMP-1 activity was not detectable in groups A and B. Conclusion The exogenous hMMP-1 gene is successfully transfected into BMSCs of rats via recombinant adenovirus and can highly express, which lays the experimental foundation for the treatment of liver fibrosis with a combination of BMSCs and hMMP-1 gene transplantation.
Objective To investigate the possibility of gene therapy of osteolysis around artificial joint prosthesis by constructing the recombinant adenovirus which can silence tumor necrosis factor α (TNF-α). Methods The primer of small interfering RNA (siRNA) coding sequence of silent TNF-α was designed and amplified, and then RAPAD adenovirus packaging system was used to load the sequence to adenovirus, and the recombinant adenovirus Ad5-TNF-α-siRNA-CMVeGFP which lacked both E1 and E3 regions was constructed. Then 64 female BABL/C mice (weighing, 20-25 g) were randomly divided into 4 groups (n=16): blank control (group A), positive control (group B), simple adenovirus (group C), and treatment group (group D). The prosthetic-model was established in group A, and the prosthetic-loosening-model in groups B, C, and D. At 2 weeks after modeling, PBS solution was injected first, and then the same solution was injected 24 hours later in group A; titanium particle solution was injected, and then PBS solution, Ad5 E1-CMVeGFP (1 × 109 PFU/mL), and Ad5-TNF-α-siRNA-CMVeGFP (1 × 109 PFU/mL) were injected, respectively in groups B, C, and D 24 hours later, every 2 weeks over a 10-week period. The general condition of mice was observed after operation. The tissues were harvested for histological observation, and the expression of TNF-α was detected by Western blot at 12 weeks after operation. Results The positive clones were achieved by enzyme digestion and confirmed by DNA sequencing after loading the target genes into adenovirus vector, and then HEK293 cells were successfully transfected by recombinant adenovirus Ad5-TNF-α-siRNA-CMVeGFP. All mice survived to the completion of the experiment. Histological observation showed that there were few inflammatory cells and osteoclasts in group A, with a good bone formation; there were a large number of inflammatory cells and osteoclasts in groups B and C, with obvious bone destruction; inflammatory cells and osteoclasts in group D was less than those in groups B and C, with no obvious bone destruction. Significant difference was found in the limiting membrane thickness and the number of osteoclasts (group A lt; group D lt; group B lt; group C, P lt; 0.05). Western blot showed that the TNF-α expression levels were 0.235 ± 0.022, 0.561 ± 0.031, 0.731 ± 0.037, and 0.329 ± 0.025 in groups A, B, C, and D respectively, showing significant difference among 4 groups (P lt; 0.05). Conclusion The recombinant adenovirus for silencing TNF-α is successfully constructed, which can effectively inhibit osteolysis by silencing TNF-α expression in the tissues around prosthesis in mice.
Objective To construct a recombinant adenovirus vector containing human vascular endothelial growth factor 165 (hVEGF165) [pAdxsi-enhanced green fluorescent protein (EGFP)-hVEGF165], and to observe the expression ofhVEGF165 by transfecting pAdxsi-EGFP-hVEGF165 into rat bone marrow mesenchymal stem cells (BMSCs) in vitro so as to lay a foundation for further research on gene therapy of blood vessel regeneration. Methods hVEGF165 was l iberated from plasmid and was subcloned into pShuttle-EGFP. The pShuttle-cytomegalo-virus-EGFP was then transferred to pAdxsi vector, by which pAdxsi-EGFP-hVEGF165 virus plasmid was obtained and was identified by enzymes restriction analysis and gene sequencing. The pAdxsi-EGFP-hVEGF165 was l inearized by digestion with restriction endonuclease PacI, and was then transfected into human embryonic kidney cells (HEK293). The retrieved recombinant adenovirus was titrated by using 50% tissue culture infective dose assay. The rat BMSCs were cultured and were infected with recombinant adenovirus containing EGFP (pAdxsi-EGFP). The multipl icities of infection (MOI) of transfection were determined by fluorescent inverted phase contrast microscope and flow cytometry (FCM), by which the most optimal value of MOI was confirmed and was used for transfecting pAdxsi-EGFP-hVEGF165 into BMSCs. The expression of hVEGF165 gene was indentified by performing Western blot, RT-PCR, and ELISA. The effect of transfection on BMSCs prol iferation was assessed by MTT. Results The expression of hVEGF165 cDNA in recombinant adenovirus plasmid was indentified by enzymes restriction analysis and gene sequencing. The titer of virus could be up to 1 ×1010 pfu/mL after several rounds of transfection and ampl ification. The efficiency of transfection on FCM was 88% when MOI being 150 pfu/ cell, at which the most optimal of MOI was achieved, as observed on fluorescence. The expressions of hVEGF165 at both mRNA and protein levels were detected after 48 hours of the transfection. The results of ELISA showed the expression ofhVEGF165 peaked at 7 days, and the production was found even after 20 days. Furthermore, the expression of hVEGF165 protein at 1, 3, 5, 7, 9, 11, 13, 15, and 20 days in the group transfected with pAdxsi-EGFP-hVEGF165 was significantly higher than that in the group transfected with pAdxsi-EGFP and in untransfected group (P lt; 0.05). The results of MTT demonstrated that here was no significant difference in absorbance (A) value between transfected with pAdxsi-EGFP-hVEGF165 group and untransfected group (P gt; 0.05). Conclusion BMSCs are suitable for gene transfection, and hVEGF165 gene can be transferred into BMSCs with high efficiency using pAdxsi-EGFP-hVEGF165 at a MOI of 150 pfu/cell. The transfected BMSCs can highly express hVEGF165, which has no effect on BMSCs growth and prol iferation.
Objective To construct a recombinant adenovirus vector pAdxsi-GFP-NELL1 that co-expressing green fluorescent protein (GFP) and homo sapiens NEL-l ike 1 (NELL1) protein (a protein bly expressed in neural tissue encoding epidermal growth factor l ike domain), to observe its expression by transfecting the recombinant adenovirus into rat bone marrow mesenchymal stem cells (BMSCs) so as to lay a foundation for further study on osteogenesis of NELL1 protein. Methods From pcDNA3.1-NELL1, NELL1 gene sequence was obtained, then NELL1 gene was subcloned into pShuttle-GFP-CMV (-)TEMP vector which was subsequently digested with enzyme and insterted into pAdxsi vector to package the recombinant adenovirus vector (pAdxsi-GFP-NELL1). After verified by enzyme cutting and gel electrophoresis, pAdxsi-GFPNELL1 was ampl ified in HEK293 cells and purified by CsCl2 gradient purification, titrated using 50% tissue culture infective dose (TCID50) assay. The rat BMSCs were cultured and identified by flow cytometry and directional induction, then were infected with adenoviruses (pAdxsi-GFP-NELL1 and pAdxsi-GFP). NELL1 expression was verified by RT-PCR and immunofluorescence; GFP gene expression was verified by the intensity of green fluorescence under fluorescence microscope. Cell counting kit-8 (CCK-8) was used for investigate the influence of vectors on the prol iferation of rat BMSCs. Results Recombinant adenoviral vector pAdxsi-GFP-NELL1, which encodes a fusion protein of human NELL1, was successfully constructed and ampl ified with titer of 1 × 1011 pfu/mL. The primary BMSCs were cultured and identified by flow cytometric analysis, osteogenic and adipogenic induction, then were used for adenoviral transfection efficiency and cell toxicity tests. An multipl icity of infection of 200 pfu/cell produced optimal effects in transfer efficiency without excessive cell death in vitro. Three days after transfection with 200 pfu/cell pAdxsi-GFP-NELL1 or pAdxsi-GFP, over 60% BMSCs showed green fluorescent by fluorescence microscopy. Imunofluorescence with NELL1 antibody also revealed high level expression of human NELL1 protein in red fluorescent in these GFP expressing cells. RT-PCR analysis confirmed that the exogenous expression of NELL1 upon transfection with pAdxsi-GFPNELL1 at 200 pfu/cell, whereas NELL1 remained undetectable in Ad-GFP-transfected rat BMSCs. The prol iferative property of primary rat BMSCs after adenoviral NELL1 transfection was assayed by CCK-8 in growth medium. Growth curve demonstratedno significant difference among BMSCs transfected with pAdxsi-GFP-NELL1, pAdxsi-GFP, and no treatment control at 7 days (P gt; 0.05). Conclusion Recombinant adenovirus vector pAdxsi-GFP-NELL1 can steady expressing both GFP and NELL1 protein after being transfected into rat BMSCs. It provides a useful tool to trace the expression of NELL1 and investigate its function in vitro and in vivo.
Objective To evaluate the transfection efficiency and expression level of hepatocyte growth factor (HGF) by transfecting a recombinant adenovirus carrying HGF gene (Ad-HGF) into bone marrow mesenchymal stem cells (BMSCs) and to explore the effect of the expression supernatant on BMSCs in vitro so as to lay a foundation for the manufacture of gene medicine which expresses efficient cell factors. Methods Rat BMSCs were isolated using Percoll density gradient method and cultured according to the adherent property of BMSCs. The expression of c-Met was detected by immunohistochemical examination. BMSCs were infected with a recombinant adenovirus carrying green fluorescent protein gene (Ad-GFP) at multipl icity of infection (MOI, 0, 25, 50, 100, and 200 pfu/cell). To select an optimal MOI, the transfection efficiency and the degree of cell damage were assayed by flow cytometry and MTT, respectively, at 48 hours after transfecting. The expression of HGF in BMSCs transfected with optimal MOI Ad-HGF was measured with ELISA assay. MTT method was used to evaluate the prol iferation effect of HGF expression supernatant on BMSCs. Results Immunohistochemical staining showed that BMSCs expressed c-Met receptor for HGF. At 48 hours after transfecting with different MOI Ad-GFP (0, 25, 50, 100, and 200 pfu/cell), the transfection efficiencies were 0.34% ± 0.04%, 40.72% ± 0.81%, 61.72% ± 1.04%, 85.33% ± 0.83%, and 17.91% ± 0.63%, respectively; and the highest transfection efficiency was observed at 100 pfu/cell MOI. The cell damage was obviously observed when MOI was 200 pfu/cell. The expression of HGF in BMSCs reached the highest level after being transfected with 100 pfu/cell MOI Ad-HGF for 48 hours. The expression product could stimulate the prol iferation of BMSCs. The prol iferation of BMSCs gradually rose with the increase of HGF protein, and reached the highest level at 10% (320 pg). Conclusion BMSCs can be transfected efficiently with Ad-HGF and express HGF protein, which stimulates the prol iferation of BMSCs. It suggests that BMSCs is an ideal repair cells with gene vector.
Objective To design, construct and select the optimal repl ication-defective recombinant adenovirus mediated short hairpin RNA (shRNA) which is transduced into human osteosarcoma cells to silence c-myc gene expression, and to construct the recombinant adenovirus vector expressing c-myc-shRNA and determine its viral titer. Methods Three pairs of complementary single-stranded ol igonucleotides (ss ol igos) were designed and synthesized, and then they were annealed to create a double-stranded ol igonucleotide (ds ol igos).The ds ol igos were cloned into pENTR/U6 vector to produce the shuttle plasmid pENTR/U6-shRNA, which was transduced into osteosarcoma cells by l iposome after sequencing. The plasmid with good silence effect was chosen by RT-PCR to perform the LR recombination reaction to the adenovirus backbone plasmid. The expression clone was transfected into HEK293A cells to produce repl ication-incompetent recombinant adenovirus mediated shRNA against c-myc whose cytopathic effect was observed and viral titer was determined by the viral particle (VP) method and 50% tissue culture infective dose (TCID50). Results Ds ol igos, which was verified by electrophoresis, was cloned into pENTR/U6 vector to produce pENTR/U6-shRNA shuttle plasmid, which was confirmed to be corrected by sequencing. The optimal plasmid with good silence effect was chosen by RT-PCR from the three pairs of double-stranded ol igonucleotide. By Pac I enzyme, the l inearrization repl ication-defective recombinant adenovirus mediated shRNA was constructed to perform the LR recombination reaction to the adenovirus backbone plasmid. The cytopathic effect and vacuole phenomenon of adenovirus mediated shRNA appeared at 3 days and became obvious at 6 days. The adenovirus virus titer in the first generation was 5.23 × 109 VP/mL, and reached 2.26 × 1012 VP/mL via 3-4 generations’ ampl ification. The viral titer was 10-3.8/0.1 mL determined by VP method and TCID50. Conclusion The recombinant adenovirus mediated shRNA c-myc is constructed in vitro through RNA interference technology.