Construction of adenovirus vectors encoding the lumican gene by gateway recombinant cloning technology

AIM： To construct adenovirus vectors of lumican gene by gateway recombinant cloning technology to further understand the role of lumican gene in myopia. METHODS： Gateway recombinant cloning technology was used to construct adenovirus vectors. The wild-type （wt） and mutant （mut） forms of the lumican gene were synthesized and amplified by polymerase chain reaction （PCR）. The lumican cDNA fragments were purified and ligated into the adenovirus shuttle vector pDown- multiple cloning site （MCS）-/internal ribozyme entry site （IRES）/enhanced green fluorescent protein （EGFP）. Then the desired DNA fragments were integrated into the destination vector pAV.Desld yielding the final expression constructs pAV.Exld-CMV〉wt-lumican/IRES/ EGFP and pAV.Exld-cytomegalovirus （CMV） 〉mutlumican/IRES/EGFP, respectively.RESULTS： The adenovirus plasmids pAV.Exld-CMV〉 wt-lumican/IRES/EGFP and pAV.Exld-CMV 〉mutlumican/IRESlEGFP were successfully constructed by gateway recombinant cloning technology. Positive clones identified by PCR and sequencing were selected and packaged into recombinant adenovirus in HEK293 cells. CONCLUSION： We construct adenovirus vectors containing the lumican gene by gateway recombinant cloning technology, which provides a basis for investigating the role of lumicangene in the pathogenesis of high myopia.

Gene therapy for allergic rhinitis with recombinant adenovirus vector containing CTLA4Ig in mice

Objective: To examine the role of recombinant adenovirus vector containing CTLA4Ig gene(Ad-CTLA4Ig) in the treatment of induced allergic rhinitis in mice.Methods: Allergic rhinitis was induced by sensitizing and challenging with ovalbumin(OVA).Ad-CTLA4Ig was intraperitoneally injected 30 min before OVA challenge.Adenovirus vector without inserted CTLA4Ig cDNA served as the control.The symptoms and morphological changes of nasal mucosa of each group were observed, and the serum levels of IgE against OVA were detected with ELISA.Results: There were no obvious symptoms and pathological changes in Ad-CTLA4Ig treated group, in which the serum OVA-specific IgE levels were significantly lower than that in control groups(P< 0.05).Conclusion: Ad-CTLA4Ig prevents and treats allergic rhinitis of mice,implying the possibility of the usage of Ad-CTLA4Ig against allergic rhinitis in clinic in future.

Construction and Expression of Human PTEN Tumor Suppressor Gene Recombinant Adenovirus Vector

The recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene was constructed by using AdEasy-1 system and its expression was detected in human breast cancer cell line MDA-MB-468. Human PTEN cDNA was cloned into adenovirus shuttle plasmid pAdTrack-CMV to generate a recombinant plasmid pAdTrack-CMV-PTEN, then homologeous recombination was carried out in the E. coli BJ5183 by contransforming linearized shuttle vector with adenovirus backbone plasmid pAdEasy-1. The newly recombined defective adenovirus vector Ad- PTEN containing green fluorescent protein （GFP） was packaged and propagated in 293 cells. After being purified by cesium chloride gradient centrifugation, the adenovirus was transfected into human breast cancer cell line MDA-MB-468 in vitro. The expression of PTEN mRNA and protein in infected human breast cancer cell line MDA-MB-468 was detected by RT-PCR and Western blot respectively. The recombinant defective adenovirus vector carrying PTEN gene was constructed successfully. The viral titer of purified adenovirus was 2. 5 × 10^10 pfu/mL, and about 70 % breast cancer cells were infected with Ad-PTEN when multiplicity of infection （MOI） reached 50. The exogenous PTEN mRNA and protein were expressed in MDA-MB-468 cells infected with Ad-PTEN by RT-PCR and Western blot. The recombinant defective adenovirus vector of PTEN gene was constructed successfully using AdEasy-1 system rapidly, which paved a sound foundation for gene study of breast cancer.

Construction and expression of SET gene and siRNA recombinant adenovirus vectors

Objective:To construct SET gene recombinant adenovirus vector and SET gene small interfering RNA(SiRNA) recombinant adenovirus vector for over-expression or knock-down of SET levels. Methods:The cDNA sequence of SET was cloned by reverse transcriptive polymerase chain reaction(RT-PCR) and the SET gene fragment was subcloned into adenovirus shuttle plasmid pAdTrack-CMV to construct the shuttle plasmid pAdTrack-SET.The shuttle plasmid pAdtrack-SET was transformed into BJ5183 cells with the adenoviral backbone pAdEasy-1 to obtain the homologous recombinant Ad-CMV-SET and the recombinant Ad-CMV-SET was packaged and amplified in the AD293 cells.The expression of SET in AD293 cells was detected by Western blot.In addition,we constructed SET gene SiRNA recombinant adenovirus vector(Ad-H1-SiRNA/SET) and its efficacy of knockdown of SET protein was detected in infected GC-2spd(ts) cells by Western blot. Results:The recombinant adenovirus vectors,both SET gene recombinant adenovirus vector Ad-CMV-SET and SET gene SiRNA recombinant adenovirus vector Ad-H1-SiRNA/SET,were proven to be constructed successfully by the evidence of endonulease digestion and sequencing.AD293 cells infected with either recombinant adenovirus vector of Ad-CMV-SET or Ad-H1-SiRNA/SET were observed to express GFP.The expression of SET protein was up-regulated significantly in AD293 cells infected with SET gene recombinant adenovirus vector.On the contrast, SET protein was significantly down-regulated in the GC-2spd(ts) cells infected with Ad-H1-SiRNA/SET (P<0.05) and the knockdown efficiency was approximately 50%-70%. Conclusion:The recombinant adenovirus vector Ad-CMV-SET and Ad-H1-SiRNA/SET were successfully constructed and effectively expressed in germ cells and somatic cells.It provides an experimental tool for further study of SET gene in the physiological and pathophysiological mechanism of reproduction-related diseases.

Construction of the recombinant adenovirus vectors of CALB_2 gene and small interfering RNA,and application in testicular Leydig cells

Objective:To construct the recombinant adenovirus vectors of calretinin(CALB_2) gene and small interfering RNA(siRNA),for over-expression or knock-down of CALB_2,as the basis of functional investigation of CALB_2 in testicular Leydig cells. Methods:The cDNA sequence of CALB_2 was cloned by the reverse transcriptive polymerase chain reaction (RT-PCR).A CALB_2 gene fragment was sub-cloned into adenovirus shuttle plasmid pAdTrack-CMV to construct the shuttle plasmid pAdTrack-CALB_2.Then it was transformed into BJ5183 cells with the adenoviral backbone pAdEasy-1 to obtain the homologous recombinant AdCMV-CALB_2.The recombinant AdCMV-CALB_2 was further packaged and amplificated in AD293 cells.The expression of CALB_2 protein in AD293 cells was detected by Western blotting.CALB_2 protein was over-expressed in mouse Leydig cell line(MLTC-1 cells) by the constructed AdCMV-CALB_2. CALB_2 gene siRNA recombinant adenovirus vector(Ad-H1-siRNA/CALB_2 was also constructed simultaneously. Its efficacy was detected in AD293 cells by Western blotting. Results:The CALB_2 gene recombinant adenovirus vector AdCMV-CALB_2 and the CALB_2 gene siRNA recombinant adenovirus vector Ad-H1-siRNA/CALB_2 were constructed successfully by endonulease digestion and sequencing. AD293 cells infected with AdCMV-CALB_2 or Ad-H1-SiRNA/CALB_2 significantly expressed GFP protein. The expression of CALB_2 protein was significantly up-regulated in AD293 cells infected with AdCMV-CALB_2 plasmids, while the expression of CALB_2 protein was down-regulated by 60%in the CALB_2 cells infected with Ad-H1-SiRNA/CALB_2. MLTC-1 cells did not markedly express CALB_2 protein,while MLTC-1 cells infected with AdCMV-CALB_2 expressed CALB_2 protein at a high level. Conclusions:The recombinant adenovirus vectors of AdCMV-CALB_2 and Ad-H1-SiRNA/CALB_2 were successfully constructed.Both vectors effectively expressed in AD293.CALB_2 protein was over-expressed in the cultured MLTC-1 cells by AdCMV-CALB_2.These vectors of CALB_2 gene and Leydig cell line are useful tools for investigating the testicular function.

Gene transfer into primary cultures of fetal neural stem cells by a recombinant adenovirus carrying the gene for green fluorescent protein

Objective: To evaluate the transduction efficiency of a recombinant adenovirus carrying the gene for green fluorescent protein (Ad-GFP) into the primary cultures of fetal neural stem cells (NSCs) by the expression of GFP. Methods: The Ad-GFP was constructed by homologous recombination in bacteria with the AdEasy system; NSCs were isolated from rat fetal hippocampus and cultured as neurosphere suspensions. After infection with the recombinant Ad-GFP, NSCs were examined with a fluorescent microscopy and a flow cytometry for their expression of GFP. Results: After the viral infection, flow cytometry analysis revealed that the percentage of GFP-positive cells was as high as 97.05%. The infected NSCs sustained the GFP expression for above 4 weeks. After differentiated into astrocytes or neurons, they continued to express GFP efficiently. Conclusion: We have success- fully constructed a viral vector Ad-GFP that can efficiently infect the primary NSCs. The reporter gene was showed fully and sustained expression in the infected cells as well as their differentiated progenies.

Rapid construction of phosphatase and tensin homolog-deleted on chromosome ten gene recombinant adenovirus using the AdEasy system

Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten （PTEN） gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely used, greatly simplifies preparation of recombinant adenovirus. Therefore, recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene （Ad-PTEN） was constructed using the AdEasy-1 system and was transfected into HEK293 cells for packaging and amplification. Infection efficiency and expression intensity were observed in primary cultured rat hippocampal neurons infected with Ad-PTEN in vitro. Results revealed a cytopathic effect in green fluorescent protein expression, which increased with prolonged time. After three cycles of amplification, the adenovirus titer was increased to an adequate titer for infecting hippocampal neurons. The entire process typically requires 4-5 weeks for completion. Results suggested that recombinant defective adenovirus vector carrying the PTEN gene was successfully and rapidly constructed using the AdEasy system.

Antiapoptotic Effect of Gene Therapy with Recombinant Adenovirus Vector Containing Hypoxia-inducible Factor-1α after Cerebral Ischemia and Reperfusion in Rats

Background：Mounting evidence has demonstrated that hypoxia-inducible factor-1α （HIF-1α） could attenuate brain injuries after cerebral ischemia and reperfusion （CIR）.However,few reports have addressed the therapeutic efficacies of a recombinant adenovirus vector containing HIF-1o （AdHIF-1o） gene after ischemia and reperfusion.The aim of this study was to examine the antiapoptotic and neuroprotective effects ofAdHIF-1o gene for cerebral injuries after ischemia and reperfusion in rats.Methods：From February to December 2016,male Sprague-Dawley rats were randomly divided into normal,sham,CIR,AdHIF-1α,and recombinant adenovirus （Ad） groups.Middle cerebral artery occlusion model was established by Longa＇s method and reperfusion resumed at 2 h postocclusion.AdHIF-1α solution,Ad solution,and phosphate-buffered saline were injected into the right lateral ventricle of rats in AdHIF-lα,Ad,and CIR groups.Brain tissue sections were observed under fluorescent microscope to confirm the definite expression of recombinant adenovirus in Ad and AdHIF-1o groups.The expressions of HIF-lα protein were analyzed by immunohistochemical staining at 6 h,24 h,and 72 h postreperfusion.Brain water content and neurological deficit scores were evaluated at 6 h,24 h,and 72 h postreperfusion.Pathological brain injuries were examined after hematoxylin and eosin stain and nerve cell apoptosis was measured after terminal-deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling （TUNEL） stain at 72 h postreperfusion.Comparisons were conducted with one-way analysis of variance by post hoc Scheffe＇s test among different experimental groups.Results：Green fluorescent protein was successfully expressed in brain tissue ofAd andAdHIF-1α groups from 24 h to 21 days postinjection.As detected by immunohistochemical staining,the expressions of HIF-lα protein were obviously enhanced in AdHIF-1o group than those in CIR and Ad groups at 24 h and 72 h postreperfusion,respectively.There were significant reductions of brain water content （78.83% ± 0.34% vs.83.21% ± 0.50% and 83.35% ± 0.32%;84.13% ± 0.24% vs.89.76% ± 0.34% and 89.70% ± 0.18%;respectively;all P 〈 0.05） and neurological deficit scores （2.90 ± 0.74 vs.3.50 ± 0.52 and 3.60 ± 0.53 at 24 h;2.40 ± 0.84 vs.3.60 ± 0.52 and 3.50 ± 0.53 at 72 h;respectively;all P 〈 0.05） in AdHIF-1 α group versus CIR and Ad groups at 24 h and 72 h postreperfusion,respectively.The pathologic changes ofAdHIF-1 α group were milder than those in CIR and Ad groups at 72 h postreperfusion.The percentage of TUNEL-positive cells in cerebral subcortex decreased significantly in AdHIF-1α group versus CIR and Ad groups at 72 h postreperfusion （P 〈 0.05）.Conclusion：AdHIF-1α has an obvious neuroprotective effect on ischemia and reperfusion in rat brains possibly through inhibiting the apoptosis of nerve cells.

Construction and Characterization of a Novel Recombinant Attenuated and Replication-Deficient Candidate Human Adenovirus Type 3 Vaccine:"Adenovirus Vaccine Within an Adenovirus Vector"

Human adenoviruses(HAd Vs)are highly contagious and result in large number of acute respiratory disease(ARD)cases with severe morbidity and mortality.Human adenovirus type 3(HAd V-3)is the most common type that causes ARD outbreaks in Asia,Europe,and the Americas.However,there is currently no vaccine approved for its general use.The hexon protein contains the main neutralizing epitopes,provoking strong and lasting immunogenicity.In this study,a novel recombinant and attenuated adenovirus vaccine candidate against HAd V-3 was constructed based on a commercially-available replication-defective HAd V-5 gene therapy and vaccine vector.The entire HAd V-3 hexon gene was integrated into the E1 region of the vector by homologous recombination using a bacterial system.The resultant recombinants expressing the HAd V-3 hexon protein were rescued in AD293 cells,identified and characterized by RT-PCR,Western blots,indirect immunofluorescence,and electron microscopy.This potential vaccine candidate had a similar replicative efficacy as the wild-type HAd V-3 strain.However,and importantly,the vaccine strain had been rendered replication-defective and was incapable of replication in A549 cells after more than twentygeneration passages in AD293 cells.This represents a significant safety feature.The mice immunized both intranasally and intramuscularly by this vaccine candidate raised significant neutralizing antibodies against HAd V-3.Therefore,this recombinant,attenuated,and safe adenovirus vaccine is a promising HAd V-3 vaccine candidate.The strategy of using a clinically approved and replication-defective HAd V-5 vector provides a novel approach to develop universal adenovirus vaccine candidates against all the other types of adenoviruses causing ARDs and perhaps other adenovirus-associated diseases.

Inhibition of vascular smooth muscle cell proliferation by in troduction of retinoblastoma gene via a recombinant adenovirus vector

This study was supported in part by grant from National Natural Science Foundation of China (No. 39570775). Objective To investigate the vascular smooth muscle cell (SMC) growth suppression by recombinant adenovirus vector expressing a retinoblastoma (Rb) protein and to explore a gene therapy approach for vascular proliferative disorders including atherosclerosis and artery restenosis. Methods A replication deficient adenovirus vector encoding a wild type Rb and AdCMVRb, was constructed and transfected into cultured rabbit aortic SMC. The efficiency of gene transfection and expression was detected by immunochemical staining and polymerase chain reaction. The role of Rb in regulating vascular SMC proliferation was observed by cell counting, thymidine incorporation, and flow cytometry. Results Wild type Rb gene transfected effectively into the cultured SMC with AdCMVRb can suppress growth factor stimulated cell proliferation through regulation of DNA synthesis and cell cycle progression. Conclusion The results demonstrate the potential of adenovirus mediated Rb gene therapy for atherosclerosis and artery restenosis after balloon angioplasty.

Recombinant adenovirus-mediated expression of GHS-R1a in HEK 293 cells

Objective To construct the recombinant adenovirus vector carrying human growth hormone secretagogue receptor type 1a （GHS-R1a） ,for genetic transfection.Methods The full-length human GHS-R1a gene was obtained by PCR amplification and then cloned into the shuttle plasmid pAdTrack-CMV.The linearized plasmid pAdTrack-CMV-GHS-R1a was co-transformed into Escherichia coli （E.coli） BJ5183 cells along with an adenoviral backbone plasmid pAdEasy1.The HEK293 cells were then infected with adenoviruses.The expression of GHS-R1a was indicated by green fluorescent protein （GFP） ,and confirmed by Reverse Transcription Polymerase Chain Reaction （RT-PCR） and Western blot.Results Enzymatic digestion of pAdGHS-R1a yielded a large fragment （approximately 30 kb） and a small fragment （4.5 kb） ,indicating the success-ful construction of recombinant adenovirus expression vector.Expression of GFP was observed by confocal laser scanning microscopy at 24 h after infection.RT-PCR and Western blot further confirmed that GHS-R1a was efficiently expressed in 293 cells.Conclusion Recombinant adenovirus （AdGHS-R1a） is successfully constructed,and the target gene can be expressed efficiently in 293 cells,which provide a valuable tool for further studying the function of GHS-R1a.

猪轮状病毒VP4基因重组腺病毒的构建及抗体水平评价

【目的】构建猪轮状病毒(Porcine rotavirus,PoRV)流行株PoRV G9P[23]型的VP4基因重组腺病毒,为开发PoRV候选基因工程疫苗奠定基础。【方法】参考GenBank中流行株PoRV G9P[23]型的VP4基因序列(登录号:MH898990.1)合成PoRV VP4基因,将得到的目的基因与腺病毒穿梭载体pAdTrack-CMV进行重组,转化大肠杆菌Top10感受态细胞,构建腺病毒穿梭载体pAdTrack-CMV-VP4;腺病毒穿梭载体经过PmeⅠ内切酶线性化处理后与含有腺病毒骨架pAdEasy-1的大肠杆菌BJ5183感受态细胞进行同源重组获得重组质粒pAd-VP4,对重组质粒进行PacⅠ酶切鉴定,并转化大肠杆菌DH5α感受态细胞。将重组质粒转染HEK293A细胞获得重组腺病毒rAd-VP4,对该重组腺病毒进行扩大培养并测定重组腺病毒的半数组织培养感染剂量(TCID50);通过RT-PCR检测其体外表达情况,Western blotting检测其反应原性;将制备的重组腺病毒用不同病毒滴度和不同免疫次数对小鼠进行腹腔免疫,收集血清通过ELISA法测定IgG抗体水平。【结果】RT-PCR扩增出1条大小为2343 bp的rAd-VP4重组腺病毒条带,测序结果正确,表明重组腺病毒rAd-VP4构建成功,测得rAd-VP4病毒滴度为106.5TCID50,Western blotting结果表明,重组腺病毒rAd-VP4在蛋白水平上得到了正确表达,蛋白的分子质量约为87 ku。小鼠IgG抗体检测结果表明,在用106.5TCID50rAd-VP4免疫后的第35和42天,小鼠血清中的IgG抗体水平显著高于105.3TCID50TGE-PED-PRV三联活疫苗IgG抗体水平(P<0.05);106.5TCID50rAd-VP4在免疫后第35和42天产生的抗体水平显著高于105.5和104.5TCID50rAd-VP4(P<0.05),而105.5TCID50rAd-VP4在免疫后第28天产生的抗体水平显著高于106.5和104.5TCID50rAd-VP4(P<0.05)。106.5TCID50rAd-VP4的2次免疫和3次免疫产生的IgG抗体在不同免疫时间均差异不显著(P>0.05)。【结论】本研究成功构建了重组腺病毒rAd-VP4,其病毒滴度为106.5TCID50。106.5和105.5TCID50rAd-VP4分别在第42和28天产生较高的IgG抗体水平,2次免疫和3次免疫对产生IgG抗体水平均无显著影响。试验结果可为开发PoRV重组腺病毒候选疫苗提供参考。

携带野生型PTEN基因的腺病毒载体的构建

目的构建携带野生型PTEN(Phosphatase and tensin homolog deleted on chromosome ten)基因的腺病毒载体,为研究PTEN功能和作用机制提供手段。方法将野生型PTEN基因克隆入含有绿色荧光蛋白(Green fluorescence protein,GFP)基因的pAdTrack-CMV质粒,在含有pAdEasy-1病毒骨架的BJ5183大肠杆菌内进行同源重组;重组子通过脂质体介导转染AD293细胞,并在AD293细胞内包装为具有感染能力的病毒颗粒;通过反复感染扩增病毒以达到感染靶细胞的适当滴度,通过GFP表达来监控腺病毒扩增;Westernblot检测靶细胞内PTEN蛋白的表达。结果感染腺病毒载体的AD293细胞表达GFP,随着时间逐渐增强,并且出现明显的细胞病变效应(Cytopathiceffect,CPE),经过3轮扩增,病毒达到合适的滴度。受腺病毒感染心肌细胞内PTEN蛋白表达明显增高。结论成功构建了携带PTEN基因的腺病毒载体。

突变k-ras基因重组腺病毒的构建

目的 利用细菌内同源重组法构建含 1 2密码子点突变的k ras基因重组腺病毒。方法 用限制性内切酶kpnⅠ +xhoⅠ从载体pcDNA3 k ras1 2 (Val)中切出 1 2密码子点突变的k ras基因片断 ,亚克隆至经同样酶切的腺病毒穿梭质粒pAdTrack CMV中 ,形成转移质粒pAdTrack CMV/k ras 1 2 (Val) ,将之PmeⅠ酶切线性化后与腺病毒基因重组质粒pAdEasy 1共转化大肠杆菌BJ51 83 ,抽提经鉴定含目的基因的重组体质粒 ,PacⅠ酶切后用脂质体转染 2 93细胞 ,包装成重组体腺病毒Ad k ras1 2 (Val)。采用PCR方法对重组体腺病毒进行鉴定 ,利用穿梭质粒pAdTrack CMV中带有GFP报告基因 ,对病毒滴度和感染效率进行监测。结果 利用CaCl2 法由pAdTrack CMV/k ras 1 2 (Val)和pAdEasy 1共转化大肠杆菌BJ51 83 ,可获得 2 5%左右的阳性重组体细菌克隆。PCR检测表明重组腺病毒已含有目的基因 ,滴度为 1 .2× 1 0 1 2 pfu/ml。结论 细菌内同源重组法构建腺病毒相比于传统的细胞内同源重组法 ,具有成功率高、方法简便、快捷、实验周期短的优点 。

PTEN cDNA重组腺病毒载体的构建

目的:应用同源重组法构建含野生型抑癌基因PTEN cDNA的腺病毒载体pAdPTEN cDNA,产生重组腺病毒AdPTEN。方法:将PTEN cDNA自载体pcDNA3-PTEN cDNA中切出,亚克隆至穿梭质粒pShuttle-CMV中,然后与腺病毒质粒pAdeasy-1在大肠杆菌BJ5183中同源重组,产生重组PTEN cDNA的腺病毒载体pAdPTEN cDNA,通过脂质体介导将pAdPTEN cDNA转染至HEK293细胞,产生有感染能力的腺病毒AdPTEN,并测定其滴度。结果:产生具有感染能力的重组腺病毒AdPTEN,滴度约为5×109pfu／ml。结论:成功构建出含有PTEN cDNA的具有感染能力的腺病毒,并可获得较高的病毒滴度,为进一步研究PTEN基因的功能和相关肿瘤的基因治疗提供有效的基因转移载体。

一种重组腺病毒载体产生及操作的新方法

目的 建立一种快速、高效的产生腺病毒的实验方法。方法 将增强型绿色荧光蛋白 (EGFP)装在穿梭质粒 ,线性化后与腺病毒骨架载体一起电穿孔转染大肠杆菌 ,使之同源重组 ,产生病毒基因组质粒。后Pac酶切 ,脂质体介导转入 2 93细胞以包装出病毒。扩增后收获病毒 ,氯化铯密度梯度离心纯化 ,空斑试验测滴度。结果 5 2个大肠杆菌克隆 ,其中有 1个发生同源重组 ,产生腺病毒基因组质粒pAdEGFP ,转染 2 93细胞 ,荧光显微镜下产生绿色荧光。病毒纯化后达 10 11pfu/ml。 结论 大肠杆菌内质粒间同源重组的方法可以高效、简便、快捷地产生重组腺病毒载体 。

经犬肝动/静脉输入反义c-myc重组腺病毒的安全性研究

目的:经Beagle犬肝脏血管注射重组腺病毒介导反义c—myc基因(Ad-ASmye)载体,观测其体内分布及毒副作用,以评价Ad-ASmye治疗肝癌的临床前期安全性。方法:选择4只体重8-10 kg健康Beagle犬,全麻后开腹,经肝动脉或门静脉注射Ad-ASmyc,注射Ad-ASmye前及注射后第3,7,14,21天取肝组织及抽取静脉血化验,PCR检测Ad-ASmyc在各器官组织中的分布,常规切片观察各器官病理变化,ELISA方法检测血中抗腺病毒抗体的产生。结果:经Beagle犬肝脏血管注射后,Ad-ASmyc可持续转导正常肝细胞达3周,实验犬一般情况好,血、肝、肾功能无明显异常,在肝脏、脾脏、肾脏、胃、心脏、皮肤中可检测到重组腺病毒的分布,镜下可见Ad-ASmyc剂量依赖性的肝组织轻微的炎症反应,注射后7 d血中有抗腺病毒载体的抗体产生,14 d达高峰,21 d开始下降。结论:经Beagle犬肝动脉或门静脉途径注射Ad—ASmyc均可转导至肝细胞,Ad-AS-myc对实验犬的毒副作用较轻。

胶质细胞源性神经营养因子重组腺病毒载体穿梭质粒的构建及鉴定

构建含大鼠胶质细胞源性神经营养因子(GDNF)cDNA的重组腺病毒穿梭载体。提取新生大鼠纹状体总RNA,RTPCR克隆大鼠GDNFcDNA,产物回收后经HindⅢ和KpnⅠ双酶切,插入重组腺病毒穿梭载体pAdTrackCMV中,氯化钙法转染入大肠杆菌DH5α中,酶切、PCR及测序分析对重组质粒做进一步鉴定。结果显示大鼠GDNFcDNA被成功克隆,所克隆的GDNFcDNA与基因库注册的相同,以上结果说明本实验成功构建了GDNFcDNA重组腺病毒载体。

小鼠T-bet基因重组腺病毒载体的构建

【目的】构建小鼠T-bet基因重组腺病毒载体,为T-bet基因在支气管哮喘治疗中的作用研究提供有效的T-bet生物表达系统。【方法】采用内切酶从质粒T-bet/GFP-RV中切获约1.7kb的小鼠T-betcDNA片段,与穿梭质粒pShuttle连接,再通过稀有酶切位点将含T-betcDNA的表达盒与Adeno-X腺病毒载体骨架连接,构建重组载体pAdeno-T-bet,测序鉴定无错配及插入移位等DNA顺序改变,并转染HEK293细胞,出现CPE后取含病毒上清的细胞培养液抽提病毒DNA行PCR鉴定。【结果】PCR及酶切证实:T-betcDNA正确克隆到穿梭质粒pShuttle中,带T-betcDNA的表达盒成功重组到腺病毒载体基因组E1A缺失区,并在HEK293细胞中成功包装出具有感染活性的重组腺病毒pAdeno-T-bet。【结论】本实验成功构建了小鼠T-bet基因重组腺病毒载体,并在HEK293细胞中成功包装出重组腺病毒。

人NT3、BDNF基因Tet-on可调控重组腺病毒载体的构建和鉴定

目的 :分别构建含人神经营养素 3(NT3)基因和脑源性神经营养因子 (BDNF)基因的重组四环素可诱导的腺病毒载体 ,并进行PCR和酶切鉴定。方法 :将NT3和BDNF基因依次分别亚克隆到pIND载体和pTRE Shuttle2载体中 ,构建重组载体pTRE Shuttle2 NT3和pTRE Shuttle2 BDNF。用PI SceI和I CeuI双酶切后将所获NT3及BDNF基因片段再与线性化的腺病毒载体pAdeno X连接 ,构建成pAdeno NT3及pAdeno BDNF的重组腺病毒载体。以电穿孔转化E .coli后挑取克隆进行PCR及酶切鉴定。结果 :重组腺病毒载体的PCR鉴定表明 ,在 312bp处出现特定的条带 ;酶切鉴定证实 ,得到约 2 3kb的预期片段 ,说明人NT3、BDNF基因与腺病毒载体pAdeno X已正确连接。结论 :成功地构建了含人NT3和BDNF基因的四环素可诱导重组腺病毒载体 。