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At least 37 records · Page 2Linked to original sources

PubMed2004

Transient foamy virus vector production by adenovirus vectors.

The genome of the prototype foamy virus (PFV) has been introduced into an adenoviral/PFV hybrid vector and tested for stable in vitro gene transfer. Three different adenoviruses are used to encode: (i) the PFV structural genes gag and pol (Ad-GagPolDeltaPacI); (ii) the PFV structural gene env (Ad-Env); and (iii) the PFV vector genome (Ad-MD9) encoding the transgene (the enhanced green fluorescent protein (eGFP) gene). Following cotransduction by the three adenoviruses, the target cells become transient PFV vector-producing cells, resulting in the in situ release of recombinant PFV at a titre of up to 10(3) vector particles/ml, which can then infect surrounding cells, leading to stable integration of the expression cassette. Stable eGFP expression, observed for up to 60 days (11 passages) in cells transduced with all three adenoviral vectors, was shown by PCR to be the result of PFV integration. In contrast, cells transduced with only the adenovirus encoding the PFV vector genome showed a marked decrease in eGFP expression by passage 2 (16 days post-transduction) and did not contain integrated PFV vector. In short, this paper describes the production of a hybrid vector capable of high in vitro transduction and stable transgene expression using adenovirus and PFV vectors.

Adenoviridae↗

PubMed2000

A simple method for the rapid generation of recombinant adenovirus vectors.

Recombinant adenoviruses are useful vectors for basic research. When the vectors are used for delineating protein function, several viruses, each containing a mutated version of the transgene are compared at the same time. However, methods to generate multiple vectors simultaneously within a short time period are cumbersome. In this report, we show that a novel backbone plasmid, when cotransfected with routinely used shuttle vectors into HEK293 cells allowed for production of recombinant viruses in an average of 14 days. The recombinant viruses had no detectable wild-type virus contamination by A549 plaque assay and only three to 300 E1a copies per 109 adenovirus genomes by a sensitive PCR-based assay. Further culturing or serial amplification did not result in wild-type revertants nor did cultures show increased levels of E1a copy number by quantitative PCR. Thus, recombinant adenovirus vectors can be produced very simply, rapidly and with little to no contaminating wild-type particles. This system should facilitate the generation of multiple genetic variants by eliminating the need for time-consuming plaque purification and the need to manipulate and screen very large plasmids. We call this the RAPAd.I system.

Adenoviridae↗

PubMed2001

Efficient repetitive gene delivery to skeletal muscle using recombinant adenovirus vector containing the Coxsackievirus and adenovirus receptor cDNA.

To improve adenovirus-mediated gene delivery to skeletal muscle, we have used a recombinant adenovirus vector encoding the human Coxsackievirus and adenovirus receptor (hCAR). Because CAR is expressed at a lower level in rodent myoblasts and muscle fibers than in other tissues, we expected that elevated expression of CAR in skeletal muscle would improve the efficacy of adenovirus-mediated gene transfer. Since the mouse myoblasts, C2C12 cells, showed low sensitivity to infection by recombinant adenovirus 5, we initially infected these cells at a high multiplicity of infection (MOI) of 250 with the recombinant adenovirus containing hCAR cDNA and LacZ gene. Subsequent infection by recombinant adenovirus containing the marker gene, green fluorescence protein, became efficient even at a low MOI of 25. Thus, elevated hCAR expression in mouse muscle fibers made a second virus inoculation at low doses possible. We also demonstrated that the elevated hCAR expression did not influence muscle membrane integrity. Our results suggest that co-expression of CAR and a therapeutic gene by adenovirus vector constitutes a novel strategy to advance gene therapy for hereditary muscle diseases.

Adenoviridae↗

PubMed2000

Tumor-specific, replication-competent adenovirus vectors overexpressing the adenovirus death protein.

We have constructed two novel adenovirus (Ad) replication-competent vectors, named KD1 and KD3, that may have use in anticancer therapy. The vectors have two key features. First, they markedly overexpress the Ad death protein (ADP), an Ad nuclear membrane glycoprotein required at late stages of infection for efficient cell lysis and release of Ad from cells. Overexpression of ADP was achieved by deleting the E3 region and reinserting the adp gene. Because ADP is overexpressed, KD1 and KD3 are expected to spread more rapidly and effectively through tumors. Second, KD1 and KD3 have two E1A mutations (from the mutant dl1101/1107) that prevent efficient replication in nondividing cells but allow replication in dividing cancer cells. These E1A mutations preclude binding of E1A proteins to p300 and pRB. As a result, the virus should not be able to drive cells from G(0) to S phase and therefore should not be able to replicate in normal tissues. We show that KD1 and KD3 do not replicate well in quiescent HEL-299 cells or in primary human bronchial epithelial cells, small airway epithelial cells, or endothelial cells; however, they replicate well in proliferating HEL-299 cells and human A549 lung carcinoma cells. In cultured A549 cells, KD1 and KD3 lyse cells and spread from cell to cell more rapidly than their control virus, dl1101/1107, or wild-type Ad. They are also more efficient than dl1101/1107 or wild-type Ad in complementing the spread from cell to cell of an E1(-) E3(-) replication-defective vector expressing beta-galactosidase. A549 cells form rapidly growing solid tumors when injected into the hind flanks of immunodeficient nude mice; however, when A549 cells were infected with 10(-4) PFU of KD3/cell prior to injection into mice, tumor formation was nearly completely suppressed. When established A549 tumors in nude mice were examined, tumors injected with buffer grew 13.3-fold over 5 weeks, tumors injected with dl1101/1107 grew 8-fold, and tumors injected with KD1 or KD3 grew 2.6-fold. Hep 3B tumors injected with buffer grew 12-fold over 3.5 weeks, whereas tumors injected with KD1 or KD3 grew 4-fold. We conclude that KD1 and KD3 show promise as anticancer therapeutics.

Adenovirus E3 Proteins↗

PubMed2005

Design and synthesis of a peptide-PEG transporter tool for carrying adenovirus vector into cells.

The adenovirus vector is a promising carrier for the efficient transfer of genes into cells via the coxackie-adenovirus receptor (CAR) and integrins (alphavbeta3 and alphavbeta5). The clinical use of the adenovirus vector remains problematic however. Successful administration of this vector is associated with side effects because antibodies to this vector are commonly found throughout the human body. To make the adenovirus vector practicable for clinical use, it is necessary to design an auxiliary transporter. The present study describes the use of Arg-Gly-Asp(RGD)-related peptide, a peptide that binds to integrins, as an auxiliary transporter to aid efficient transport of adenovirus vector. Furthermore, poly(ethylene glycol) (PEG) was also used as a tool to modify the adenovirus such that the risk of side effects incurred during clinical application was reduced. The present study describes the design, preparation and use of (acetyl-Tyr-Gly-Gly-Arg-Gly-Asp-Thr-Pro-(beta)Ala)(2)Lys-PEG-(beta)Ala-Cys-NH(2)[(Ac-YGGRGDTP(beta)A)(2)K-PEG-(beta)AC] as an efficient peptide-PEG transporter tool for carrying adenovirus vector into cells. (Ac-YGGRGDTP(beta)A)(2)K-PEG-(beta)AC was coupled with 6-maleimidohexanoic acid N-hydroxysuccinimide ester and the resulting 6-[(Ac-YGGRGDTP(beta)A)(2)K-PEG-(beta)AC-succinimido]hexanoic acid N-hydroxysuccinimide ester reacted with adenovirus. The modified adenovirus with the peptide-PEG hybrid exhibited high gene expression even in a CAR-negative cell line, DC2.4.

Adenoviridae↗

PubMed1996

Systematic analysis of repeated gene delivery into animal lungs with a recombinant adenovirus vector.

Adenovirus-based vectors are promising candidates for genetic therapy of cystic fibrosis (CF). Because adenoviruses naturally infect airway cells, they grow to very high titers, and the transgenes carried by the adenoviruses are expressed at high levels. In addition, adenoviruses are relatively safe because the disease caused by the wild-type virus is self-limiting. One disadvantage of adenovirual vectors is that the transgene expression would be transient because adenoviruses do not integrate their DNA into the genome of the host cells. Adenoviral gene delivery into the lungs is also complicated by the anatomy of the airways and the defense mechanisms of the recipient. To assess the feasibility of adenovirus-mediated gene therapy for CF, a recombinant adenovirus carrying a lacZ gene was delivered into animal lungs to study the efficiency and cellular distribution of gene transfer, the duration of gene expression, the possible histopathology of the lungs after gene transfer, and the efficacy of repeated administrations of the viral agent. The results of these studies demonstrate that (i) efficient gene transfer into animal lungs can be achieved; (ii) a near-homogenous delivery of the vectors can be achieved by airway instillation, although the pattern of transduction varies among individual animals; (iii) pathological effects are generally mild in CD1 mice; (iv) gene expression is transient; (v) repetitive gene transfer is achievable, but becomes progressively less efficient, and (vi) immune responses are induced against both the viral and transgene products.

Adenoviridae↗

PubMed2004

Targeted adenovirus vectors.

Recombinant adenovirus (Ad) vectors continue to be the preferred vectors for gene therapy and the study of gene function because they are relatively easy to construct, can be produced at high titer, and have high transduction efficiency. However, in some applications gene transfer with Ad vectors is less efficient because the target cells lack expression of the primary receptor, coxsackievirus and adenovirus receptor (CAR). Another problem is the wide biodistribution of vector in tissue following in vivo gene transfer because of the relatively broad tissue expression of CAR. To overcome these limitations, various approaches have been developed to modify Ad tropism. In one approach, the capsid proteins of Ad are modified, such as with the addition of foreign ligands or the substitution of the fiber with other types of Ad fiber, in combination with the ablation of native tropism. In other approaches, Ad vectors are conjugated with adaptor molecules, such as antibody and fusion protein containing an anti-Ad single-chain antibody (scFv) or the extracellular domain of CAR with the targeting ligands, or chemically modified with polymers containing the targeting ligands. In this paper, we review advances in the development of targeted Ad vectors.

Adenoviridae↗

PubMed2002

Virucidal effects of rodent cage-cleaning practices on the viability of adenovirus vectors.

Human adenoviruses and adenoviral vectors are classified as Risk Group 2 agents and require BSL2 containment and practices. An additional consideration in using adenoviruses and viral vectors in laboratory animal studies is the possible transmission of these agents to other animals and/or personnel as a result of viral shedding in animal urine and feces. When handling BSL2 agents, cage-wash staff are required to wear appropriate personnel protective equipment, including scrubs, Tyvek suit, hair covering, dust mask, shoes covers, and gloves. Current decontamination procedures are to bag and autoclave soiled rodent cages containing bedding prior to washing in the cage washer to prevent possible adenoviral transmission. However, the practice of autoclaving softens the polycarbonate-based rodent cages, allowing damaging agents or conditions to affect the integrity of the plastic and degrade the cages. The objective of this study was to determine whether current rodent cage-cleaning practices produced virucidal effects for use in lieu of or prior to autoclaving the cages. We found that heating an Av3GFP vector in a test tube to a temperature of 74 degrees C (165 degrees F) for 6 min conditions equivalent to those of the cage washer resulted in greater than an 11-log reduction in infectivity of the vector as evaluated by its cytopathic effect on cells. The combination of heating and a liquid, phosphate-free alkaline detergent produced the same reduction in vector infectivity. However, common cage-cleaning solutions alone possessed no virucidal activity. The high temperatures used in cage-washing procedures alone or in combination with a cleaning solution reduced or eliminated the risk of transmission from viral shedding through urine and feces even at vector concentrations far greater than would ever be expected to be present. Autoclaving cages diminishes the stability and integrity of the polycarbonate cages without providing a further reduction in the risk of virus or vector transmission. On the basis of results from this study, new cage-wash recommendations include dumping the contaminated bedding into a HEPA-filtered waste disposal system and autoclaving the bags of bedding before disposal, then cleaning the cages in the rack washer at wash temperatures of 74 degrees C (165 F) and rinse temperatures of 82 degrees C (180 F).

Adenoviridae↗

PubMed1998

Persistent and secondary adenovirus-mediated hepatic gene expression using adenovirus vector containing CTLA4IgG.

Adenovirus vectors can transfer recombinant genes efficiently into a wide variety of cells in vivo, but have serious limitations: gene expression is transient and secondary gene transfer is inefficient or impossible because of cellular and humoral immune responses against adenovirus-transduced cells. To solve these limitations, we have constructed an adenovirus vector, Adex1CACTLA4IgG, that expresses CTLA4IgG molecules. After in vivo administration of Adex1CACTLA4IgG (9.0 x 10(9) PFU), the peak level of serum CTLA4IgG was 29.8 mg/ml on day 4. The serum CTLA4IgG concentration gradually fell but was still 5.7 mg/ml on day 90. However, the serum concentration of CTLA4IgG was elevated after a second administration of Adex1CACTLA4IgG. The production of antibody against adenovirus was completely prevented after treatment with Adex1CACTLA4IgG. In addition, coadministration of Adex1CALacZ with Adex1CACTLA4IgG induced persistent hepatic expression of beta-Gal molecules, while administration of Adex1CALacZ alone induced transient expression of beta-Gal molecules. More importantly, on day 160 a secondary challenge with Adex1CALacZ was possible in mice treated with Adex1CALacZ plus Adex1CACTLA4IgG. Thus, we have demonstrated that (1) gene expression of a recombinant adenovirus, Adex1CACTLA4IgG, is persistent in liver and secondary administration of this adenovirus is possible, (2) coadministration of Adex1CACTLA4IgG virus with another adenovirus, AdexCALacZ, prolongs AdexCALacZ-mediated gene expression, and (3) Adex1CACTLA4IgG is useful for secondary challenge with Adex1CALacZ.

Abatacept↗

PubMed2003

[Construction and biological activities of CTLA4Ig adenovirus vectors].

AIM: To construct CTLA4Ig adenovirus vectors (AdCTLA4Ig) by homologous recombination and study their activity, and to employ the vectors to induce cardiac transplantation tolerance by gene therapy. METHODS: CTLA4Ig gene was cloned to pCA13 adenovirus shuttle plasmid by recombination strategy. Construction of CTLA4Ig adenovirus vectors was performed by homologous recombination of pCA13 plasmid containing CTLA4Ig gene with adenovirus helper plasmid, followed by packaged with 293 cells. Expression and secretion of CTLA4Ig was confirmed by RT-PCR, SDS-PAGE and Western blot. The inhibitory effect of supernate of 293 cells infected with AdCTLA4Ig on MLR in-vitro was observed. A biological activity of CTLA4Ig adenovirus vectors was determined by AdCTLA4Ig gene therapy in rats in-vivo. RESULTS: The Construction of CTLA4Ig adenovirus vector was successful. It was confirmed that the supernatant of 293 cells infected with AdCTLA4Ig could inhibit MLR in-vitro. It was also showed that CTLA4Ig adenovirus vectors could induce transplantation tolerance and prolong allograft survival when they were administrated in rats in-vivo. CONCLUSION: CTLA4Ig adenovirus vectors successfully constructed can infect 293 package cells and secrete CTLA4Ig. The CTLA4Ig protein can inhibit T cell activation. The CTLA4Ig adenovirus vectors can be employed to gene therapy in-vivo, and induce transplantation tolerance.

Abatacept↗

PubMed1988

Trans-activation of the human immunodeficiency virus long terminal repeat sequences, expressed in an adenovirus vector, by the adenovirus E1A 13S protein.

The human immunodeficiency virus 1 (HIV-1) long terminal repeat (LTR) sequences were inserted into adenovirus in place of the E1 region. The HIV-1 LTR contained in this recombinant adenovirus responds to trans-activation by tatIII in a HeLa cell line constitutively expressing that HIV-1 gene product. In addition, the HIV-1 LTR is activated by the adenovirus E1A 13S, but not 12S or 9S, gene product when it is supplied in trans by a coinfecting wild-type adenovirus. The Rous sarcoma virus LTR, in a similar recombinant adenovirus, is insensitive to tatIII but is also trans-activated by the E1A 13S protein. The action of the 13S E1A and tatIII proteins are additive for the HIV-1 LTR in the context of adenovirus and they appear to act at the transcriptional level. As in HeLa cells, the adenovirus-borne HIV-1 LTR is inactive in the absence of a trans-activator in H9 and Jurkat cells, two human leukemic T-cell lines. This suggests that recombinant adenoviruses have diagnostic potential for the detection of trans-activators of the HIV-1 LTR that are present in circulating human lymphocytes.

Adenovirus Early Proteins↗

PubMed1997

Transfection of neonatal rat cochlear cells in vitro with an adenovirus vector.

A recombinant adenovirus vector containing a beta-galactosidase reporter gene was used to transfect neonatal rat organ of Corti or spiral ganglion explants in vitro. Infection at appropriate titers (10(6)-10(7) pfu/ml) transduced virtually all cells in the cultures after 72 hr. However, spiral ganglion neurons and cells in the inner hair cell regions of the organ of Corti showed the highest levels of expression. Viral titers that produced high levels of beta-galactosidase expression did not appear to damage the cultures, and did not inhibit neurite outgrowth from spiral ganglion cells. However, higher titers (10(8)-10(9) pfu/ml) clearly diminished explant viability and inhibited neurite extension. The results demonstrate that cochlear cells can be transfected successfully with an adenovirus vector, at viral titers which do not induce obvious signs of cellular damage or dysfunction.

Adenoviridae↗

PubMedDate not supplied

In vivo cancer gene therapy with a recombinant interleukin-2 adenovirus vector.

Recombinant adenovirus (AdV) vectors are highly efficient at in vitro and in vivo gene delivery. In vivo therapy of established murine fibrosarcoma and mammary carcinomas was attempted with intratumoral injections of a recombinant AdV vector in which the human interleukin-2 (IL-2) gene was driven by the cytomegalovirus enhancer/promoter. Delayed growth and rejection of some tumors could be achieved with a cumulative virus dose of 2 to 6 x 10(9) plaque-forming units in two or three divided doses. Lower viral doses were ineffective, and higher doses resulted in animal death due to IL-2 toxicity. Using AdV vectors with the marker genes beta-galactosidase and luciferase, it is clear that even small volume (10 to 20 microL) intratumoral injections result in substantial systemic delivery of a portion of the virus dose. These findings define the potential and limitations of in vivo AdV-based cancer gene therapy and provide support for strategies to develop tumor-specific vectors.

Adenoviridae↗

PubMed2006

Syrian hamster as a permissive immunocompetent animal model for the study of oncolytic adenovirus vectors.

Oncolytic adenoviruses represent an innovative approach to cancer therapy. These vectors are typically evaluated in immunodeficient mice with human xenograft tumors. However, in addition to being immunodeficient, this model is limited because normal and cancerous mouse tissues are poorly permissive for human adenovirus replication. This prompted us to search for a model that more accurately reflects the use of oncolytic adenoviruses in cancer patients. To this end, we developed a novel Syrian hamster model that is both immunocompetent and replication-permissive. We found that human adenovirus replicates well in Syrian hamster cell lines and confirmed replication in the lungs. Oncolytic adenovirus injection showed efficacy in three different hamster tumor models. Furthermore, i.t. oncolytic adenovirus injection resulted in suppression of primary and metastatic lesions, i.t. replication and necrosis, vector entrance into the bloodstream, replication in the liver and lungs, and anti-adenovirus antibody induction. Our findings show that the Syrian hamster is a promising immunocompetent model that is permissive to human adenovirus replication in tumors as well as normal tissues. Therefore, the Syrian hamster model may become a valuable tool for the field of oncolytic adenovirus vectors in which vector safety and efficacy can be evaluated.

Adenoviruses, Human↗

PubMed2000

Improved production of adenovirus vectors expressing apoptotic transgenes.

Adenovirus vectors expressing gene products that can induce apoptosis have potential utility in gene therapy applications ranging from the treatment of proliferative diseases to transplantation. However, adenovirus vectors carrying proapoptotic gene products are difficult to produce, as the apoptotic environment is not conducive to adenovirus gene expression and replication. Production of AdFasL/G, an adenovirus vector that expresses high levels of Fas ligand, was severely reduced in the 293 packaging cell line. Increased yields of AdFasL/G were achieved by inclusion of peptide-based caspase inhibitors in the growth medium. However, use of these inhibitors for large-scale production would be difficult and expensive. A screen for gene products that increase the yield of AdFasL/G in 293 cells revealed that the poxvirus serpin CrmA and the adenovirus 14.7K product were able to increase virus yields significantly. Apoptosis induced by AdFasL/G was attenuated in 293CrmA cell lines and virus titers were increased dramatically. However, serial passage of AdFasL/G on 293CrmA cells resulted in the generation of replication-competent adenovirus. To resolve this problem, the CrmA gene was introduced into AE25 cells, an E1-complementing cell line that has limited sequence identity with the vectors. AdFasL/G titers were increased 100-fold on AE25CrmA cells relative to the AE25 cells and RCA contamination was not detectable. In addition, adenovirus vectors that express FADD, caspase 8, and Fas/APO1 were produced efficiently in AE25CrmA and 293CrmA.

Adenoviridae↗

PubMed2000

Canine adenovirus vectors: an alternative for adenovirus-mediated gene transfer.

Preclinical studies have shown that gene transfer following readministration of viral vectors is often inefficient due to the presence of neutralizing antibodies. Vectors derived from ubiquitous human adenoviruses may have limited clinical use because preexisting humoral and cellular immunity is found in 90% of the population. Furthermore, risks associated with the use of human adenovirus vectors, such as the need to immunosuppress or tolerize patients to a potentially debilitating virus, are avoidable if efficient nonhuman adenovirus vectors are feasible. Plasmids containing recombinant canine adenovirus (CAV) vectors from which the E1 region had been deleted were generated and transfected into a CAV E1-transcomplementing cell line. Vector stocks, with titers greater than or equal to those obtained with human adenovirus vectors, were free of detectable levels of replication-competent CAV and had a low particle-to-transduction unit ratio. CAV vectors were replication defective in all cell lines tested, transduced human-derived cells at an efficiency similar to that of a comparable human adenovirus type 5 vector, and are amenable to in vivo use. Importantly, 49 of 50 serum samples from healthy individuals did not contain detectable levels of neutralizing CAV antibodies.

Adenoviridae↗

PubMed1993

In vivo gene transfer and expression in normal uninjured blood vessels using replication-deficient recombinant adenovirus vectors.

Replication-deficient recombinant adenovirus vectors do not require target cell replication for transfer and expression of exogenous genes and thus may be useful for in vivo gene therapy in the endothelium. To evaluate the feasibility of adenovirus-mediated gene transfer in vivo in normal intact blood vessels, adenovirus vectors containing the Escherichia coli lacZ gene or a human alpha 1-antitrypsin (alpha 1AT) cDNA were injected in vivo into the lumen of an occluded vessel segment of sheep jugular vein and/or carotid artery. After 15 minutes of incubation, circulation was restored; the vessels were harvested 1-28 days later and evaluated for gene transfer and expression. Three days after in vivo exposure to the lacZ adenovirus vector, the endothelium of jugular veins and carotid arteries expressed beta-galactosidase. Exposure of jugular veins and carotid arteries in vivo to the alpha 1AT adenovirus vector resulted in the expression of alpha 1AT mRNA transcripts detected by Northern analysis and in the synthesis and secretion of alpha 1AT detected by ex vivo [35S]methionine labeling. Expression with the adenovirus vectors was efficient and easily detectable 1-14 days after injection, with maximum expression at 7 days. Expression was no longer evident at 28 days. Thus, adenovirus vectors are capable of transferring exogenous genes to the endothelium of normal arteries and veins with expression for at least 2 weeks, suggesting that these vectors have the potential for a variety of cardiovascular experimental and clinical applications.

Adenoviridae↗

PubMed2006

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 X 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.

Adenoviridae↗