Application Of Adenovirus Research Articles

Inhibition of breast cancer cells by targeting E2F-1 gene and expressing IL15 oncolytic adenovirus.

The wide application of oncolytic adenovirus presents a novel therapeutic strategy for breast cancer gene therapy. Application of adenovirus alone achieves little curative effects on breast cancer. In addition, it is worth exploring the synergistic anti-tumor effect by inserting immunomodulatory factor in oncolytic adenovirus genome. By taking the advantage of the highly proliferative property of breast cancer, a novel recombinant adenovirus which could selectively kill tumor cells is established under an E2F-1 promoter. Also by carrying human Interleukin-15 (IL-15) gene, the oncolytic adenovirus exhibits an immunomodulatory effect. The present study proved that the novel oncolytic virus (SG400-E2F/IL-15) exhibits an enhanced anti-tumor activity both in vitro and in vivo, representing an experimental basis for breast cancer “virus-gene” therapy.

A new strategy for repeated application of adenovirus based vectors: proof-of-concept in rhesus macaques challenged with SIVmac239

Background It is well recognized that highly active antiretroviral therapy (HAART) can control HIV/AIDS and prolong patient’s life. However, HAART is associated with drug toxicity, drug resistant, and patient’s affordability. Therefore, developing an effective therapeutic vaccine that could induce HIV-specific immune responses may provide a solution to reduce the need of antiretroviral therapy. Adenovirus based vaccines have been extensively evaluated as a vaccine vehicle for HIV/AIDS and a variety infectious diseases, however, it has been a major concern that antiAd5 neutralizing antibodies in general population or after the first dose of immunization can hinder the its practical application. The idea of using less prevalent adenovirus serotypes lack of long-term safety record including oncogeneicity. Moreover, any adenovirus serotype will inevitablely induce neutralizing antibodies after one single use which render the strategy of using more serotypes infeasible. Methods In this study, we explored a novel “one-size-fits-all” strategy, namely AVIP (Adenoviral Vector Infected PBMC), to circumvent the attenuated efficacy of Ad-based vaccines due to anti-Ad immunity. Results We demonstrated that this AVIP strategy can elicit SIVspecific responses in both Ad5-seropositive and Ad5-seronegative macaques. Interestingly, comparable SIV-specific but weaker Ad5-specific responses were elicited in Ad5seronegative monkeys received AVIP immunization as compared to direct injection of Ad5-SIV vaccines. Then a cohort of Ad5-seropositive SIVmac239-infected monkeys received AVIP immunization with Ad5 vectors expressing SIVmac239 Gag, Pol and Env with HAART. After therapeutic immunization, SIV-specific response was induced in vaccinated monkeys whereas a slower responses were observed in non-vaccinated monkeys. The functional immunological profiles were also being detected, and we are also monitoring whether this immunological benefit would afford a virological benefit. Conclusion Our goal is to further develop the AVIP strategy as a simple but practically effective method for repeated delivery of Ad5-based vaccines in humans for HIV and other diseases.

Lentiviral Vector‐Mediated Gene Transfer to Endotherial Cells Compared with Adenoviral and Retroviral Vectors

Human immunodeficiency virus (HIV, lentivirus) vector has attractive features for gene therapy, including the ability to transduce non‐dividing cells and long‐term transgene expression. We have already reported that lentivirus vector can transduce well‐differentiated rat cardiac myocytes. Endothelial cells (EC) are an attractive target for gene therapy, both for the treatment of cardiovascular disease and for the systemic delivery of recombinant gene products directly into the circulation. There are several reports regarding application of adenovirus and retrovirus based vectors to EC. However, there have been few reports which show the effect to lentivirus‐mediated gene transfer efficiency, compared with adenovirus and retrovirus. In this study, bovine aortic endothelial cells (BAECs) were infected, in vitro, with these virus vectors. Transduction efficiency (TE) of β‐Gal gene transfer in BAECs by adenovirus, lentivirus, or retrovirus at MOI10 (Multiplicity of infection) (determined on Hela cells) is 69±11, 33±8, or 22±6% respectively. In adenovirus and lentivirus, almost 100% of BAECs were transduced at MOI 50. However, in retrovirus, TE showed only 48±6% at MOI 50 and no increase at MOI 100. The percentage of β‐Gal positive cells was decreased rapidly at longer passage of cells after being transduced by adenovirus. However, lentivirus and retrovirus showed sustained higher percentage of positive cells. Furthermore, transduction by lentiviral vectors had no significant effect on viability of BAECs. Our results indicate that lentivirus showed high‐level and long term gene expression in BAECs. Lentivirus can be an effective vector for the ex vivo, genetically modified EC implantation and in vivo gene therapy.

391. Targeted Delivery of Adenovirus Expressing eNOS to the Endothelium In Vivo Lowers Blood Pressure in Hypertensive Rats

Top of pageAbstract Background: Vascular dysfunction associated with oxidative stress is a key feature of human essential hypertension. The stroke prone spontaneously hypertensive rat (SHRSP) is a model of this condition. We have shown that local in vivo application of adenovirus encoding for either endothelial nitric oxide synthase (eNOS) or extracellular superoxide dismutase (SOD3) improves impaired nitric oxide (NO) bioavailability and endothelial function in the carotid artery of the SHRSP (1,2). The present study sought to determine the effects of systemic administration of these vectors on blood pressure in the SHRSP. Since adenovirus is sequestered and degraded by the liver we also evaluated specific targeting of vectors to the vascular endothelium, using a bispecific antibody 3. Methods: Systolic blood pressure (SBP) was recorded by radiotelemetry in 10 to 11 week-old male SHRSP for a total of 8 weeks. Four hours after infusion of 3×1011 particles of null adenovirus (to saturate hepatic Kupffer cells), rats received a single infusion of 1×1010 particles of recombinant adenoviral vectors ('RAd'), or vehicle, encoding for eNOS, SOD3 or EGFP via the femoral vein (n = 5 per group). Two further groups (n = 5) received RAdeNOS or RAdEGFP pre-incubated with a bispecific antibody (Fab9B9) which binds to both the adenoviral coat and angiotensin converting enzyme. Telemetry data was analysed using a Linear Mixed Effects Model. Results: Biodistribution studies using Lightcycler real-time PCR revealed that the vast majority of non-targeted adenoviral particles accumulated in liver, with lower levels in spleen, lung, aorta and carotid artery. Transgene expression, determined by immunohistochemistry, paralleled this pattern. Non-targeted over-expression of extracellular SOD or eNOS had no effect on SBP. However, endothelial targeting increased vector accumulation in the lung, and pulmonary eNOS immunoreactivity was increased in rats which had received Fab9B9-RAdeNOS but not Fab9B9-RAdEGFP. Functional studies found that these changes were accompanied by a significant increase in basal NO bioavailability in small pulmonary arteries. Moreover, in contrast to non-targeted vectors, Fab9B9-RAdeNOS caused a significant and sustained reduction in SBP relative to the Fab9B9-RAdEGFP control (see Figure 1). Conclusion: This study shows for the first time that specific vascular targeting of adenoviral-mediated gene delivery can modify systemic cardiovascular phenotype.

Cationic polymer and lipids augment adenovirus-mediated gene transfer to cerebral arteries in vivo.

Adenovirus-mediated gene transfer to blood vessels is relatively inefficient because binding of adenovirus to vessels is limited. The authors have reported that incorporation of cationic polymer and lipids with adenovirus augments gene transfer to blood vessels ex vivo. In this study, the authors determined whether complexes of adenovirus and cations improve efficiency of gene transfer in vivo. Poly-L-lysine, lipofectamine, or lipofectin was complexed with adenovirus encoding beta-galactosidase. Optimum ratios of the cations per adenovirus were determined by gene transfer to fibroblasts. After injection of the adenovirus into the cisterna magna of anesthetized rabbits, transgene activity was greater in the adventitia of intracranial arteries and meninges after injection of the complexes than adenovirus alone. Thirty minutes after application of adenovirus with the cations, binding of adenovirus to fibroblast cells in vitro or the basilar artery in vivo (by Southern blot analysis) was augmented, which suggests that enhanced binding of virus contributes to augmentation of transgene expression. Thus, cationic polymer and lipids improve transgene expression in intracranial arteries, primarily in the adventitia, after adenovirus-mediated gene transfer in vivo. This strategy may be applicable to studies of gene transfer and eventually for gene therapy.

Lung gene therapy: in vivo adenovirus-mediated gene transfer to rhesus monkey airway epithelium.

Somatic gene therapy of lung disorders such as cystic fibrosis (CF) aims at introducing the therapeutic gene into respiratory epithelium. We have tested the ability of recombinant human adenovirus to infect rhesus monkey airway epithelium in vivo. Application of adenovirus harboring the lacZ marker gene to the airway surface resulted in large patches of lacZ-positive cells in the trachea, bronchi, and bronchioles, 6 days after virus exposure, indicating a successful transfer of the lacZ gene to respiratory epithelium. Microscopic analysis showed that basal, mucous goblet, and ciliated cells were lacZ positive. In addition, gene transfer to the submucosal glands was observed. Pathological examination of the organs revealed no virus-mediated toxic effects to the lungs and other organs. Using polymerase chain reaction (PCR) analysis we found no spread of the virus to blood or any organ tested. These results indicate the potential use and safety of adenoviruses as a tool in human gene therapy procedures aimed at pulmonary diseases.