Assessment of a novel, capsid-modified adenovirus with an improved vascular gene transfer profile

<p>Background: Cardiovascular disorders, including coronary artery bypass graft failure and in-stent restenosis remain significant opportunities for the advancement of novel therapeutics that target neointimal hyperplasia, a characteristic of both pathologies. Gene therapy may provide a successful approach to improve the clinical outcome of these conditions, but would benefit from the development of more efficient vectors for vascular gene delivery. The aim of this study was to assess whether a novel genetically engineered Adenovirus could be utilised to produce enhanced levels of vascular gene expression.</p> <p>Methods: Vascular transduction capacity was assessed in primary human saphenous vein smooth muscle and endothelial cells using vectors expressing the LacZ reporter gene. The therapeutic capacity of the vectors was compared by measuring smooth muscle cell metabolic activity and migration following infection with vectors that over-express the candidate therapeutic gene tissue inhibitor of matrix metalloproteinase-3 (TIMP-3).</p> <p>Results: Compared to Adenovirus serotype 5 (Ad5), the novel vector Ad5T*F35++ demonstrated improved binding and transduction of human vascular cells. Ad5T*F35++ mediated expression of TIMP-3 reduced smooth muscle cell metabolic activity and migration in vitro. We also demonstrated that in human serum samples pre-existing neutralising antibodies to Ad5T*F35++ were less prevalent than Ad5 neutralising antibodies.</p> <p>Conclusions: We have developed a novel vector with improved vascular transduction and improved resistance to human serum neutralisation. This may provide a novel vector platform for human vascular gene transfer.</p&gt

A Mechanistic Paradigm for Broad-Spectrum Antivirals that Target Virus-Cell Fusion

10.1371/journal.ppat.1003297PLoS Pathogens94

Genetic Incorporation of Human Metallothionein into the Adenovirus Protein IX for Non-Invasive SPECT Imaging

As the limits of existing treatments for cancer are recognized, clearly novel therapies must be considered for successful treatment; cancer therapy using adenovirus vectors is a promising strategy. However tracking the biodistribution of adenovirus vectors in vivo is limited to invasive procedures such as biopsies, which are error prone, non-quantitative, and do not give a full representation of the pharmacokinetics involved. Current non-invasive imaging strategies using reporter gene expression have been applied to analyze adenoviral vectors. The major drawback to approaches that tag viruses with reporter genes is that these systems require initial viral infection and subsequent cellular expression of a reporter gene to allow non-invasive imaging. As an alternative to conventional vector detection techniques, we developed a specific genetic labeling system whereby an adenoviral vector incorporates a fusion between capsid protein IX and human metallothionein. Our study herein clearly demonstrates our ability to rescue viable adenoviral particles that display functional metallothionein (MT) as a component of their capsid surface. We demonstrate the feasibility of 99mTc binding in vitro to the pIX-MT fusion on the capsid of adenovirus virions using a simple transchelation reaction. SPECT imaging of a mouse after administration of a 99mTc-radiolabeled virus showed clear localization of radioactivity to the liver. This result strongly supports imaging using pIX-MT, visualizing the normal biodistribution of Ad primarily to the liver upon injection into mice. The ability we have developed to view real-time biodistribution in their physiological milieu represents a significant tool to study adenovirus biology in vivo

Gene therapy for monogenic liver diseases: clinical successes, current challenges and future prospects

Over the last decade, pioneering liver-directed gene therapy trials for haemophilia B have achieved sustained clinical improvement after a single systemic injection of adeno-associated virus (AAV) derived vectors encoding the human factor IX cDNA. These trials demonstrate the potential of AAV technology to provide long-lasting clinical benefit in the treatment of monogenic liver disorders. Indeed, with more than ten ongoing or planned clinical trials for haemophilia A and B and dozens of trials planned for other inherited genetic/metabolic liver diseases, clinical translation is expanding rapidly. Gene therapy is likely to become an option for routine care of a subset of severe inherited genetic/metabolic liver diseases in the relatively near term. In this review, we aim to summarise the milestones in the development of gene therapy, present the different vector tools and their clinical applications for liver-directed gene therapy. AAV-derived vectors are emerging as the leading candidates for clinical translation of gene delivery to the liver. Therefore, we focus on clinical applications of AAV vectors in providing the most recent update on clinical outcomes of completed and ongoing gene therapy trials and comment on the current challenges that the field is facing for large-scale clinical translation. There is clearly an urgent need for more efficient therapies in many severe monogenic liver disorders, which will require careful risk-benefit analysis for each indication, especially in paediatrics

Synthesis and duplex-stabilizing properties of fluorinated N-methanocarbathymidine analogues locked in the C3'-endo conformation

The efficient synthesis, antiviral activity, and duplex-stabilizing properties of both isomers of the 2'-fluoro analogue of Northern methanocarbathymidine (N-MCT), 2 and 3, are reported. We show that 2'-F incorporation on the N-MCT scaffold has a strong stabilizing effect on duplex thermal stability. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Synthesis and duplex-stabilizing properties of fluorinated N-methanocarbathymidine analogues locked in the C3'-endo conformation

The efficient synthesis, antiviral activity, and duplex-stabilizing properties of both isomers of the 2'-fluoro analogue of Northern methanocarbathymidine (N-MCT), 2 and 3, are reported. We show that 2'-F incorporation on the N-MCT scaffold has a strong stabilizing effect on duplex thermal stability. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Efficient delivery of angiostatin K1-5 into tumors following insertion of an NGR peptide into adenovirus capsid.

International audienceAdenovirus (Ad)-mediated delivery of anti-angiogenic molecules into tumors constitutes an appealing approach for growth inhibition. However, lack of expression on tumors of Ad receptors leads to weak tumor transduction. Therefore, to provide Ad with a new entry pathway into tumors, an NGR peptide was inserted into either fiber (AdFNGR) or hexon (AdHNGR) capsid proteins. This strategy provided Ad with a very efficient entry pathway in both endothelial cells and tumor cells, with the highest efficacy observed for AdHNGR. Using pharmacological, biochemical and genetic approaches, AdHNGR and AdFNGR were shown to bind not only to CD13 receptor, but also to alphavbeta3 integrins. Both vectors were efficient tools to deliver angiostatin K1-5 cDNA into endothelial cells, thus leading to a dramatic inhibition of their proliferation and increased cell death. Although AdHNGR and Adwt were found to display similar gene transduction efficacy in Lewis lung carcinoma (LLC), pseudotyping AdHNGR with an Ad3-fiber unmasked the ability of NGR-peptide to target these tumors. As a result, delivery of angiostatin K1-5 cDNA into highly aggressive tumors translated into a stronger inhibition of their growth. Altogether, our results suggest that NGR-bearing Ad are valuable tools to realize the potential of this anti-angiogenic approach to anti-tumor therapy.Gene Therapy advance online publication, 30 July 2009; doi:10.1038/gt.2009.97

Cross-reactive and cross-neutralizing activity of human mumps antibodies against a novel mumps virus from bats.

To evaluate the antigenic relationship between bat mumps virus (BMV) and the JL5 vaccine strain of mumps virus (MuV(JL5)), we rescued a chimeric virus bearing the F and HN glycoproteins of BMV in the genomic background of MuV(JL5) Cross-reactivity and cross-neutralization between this chimeric rMuV(JL5)-F/HN(BMV) virus and rMuV(JL5) were demonstrated using hyperimmune mouse sera and a curated panel of human sera. All mouse and human sera that were able to neutralize rMuV(JL5) infection had cross-neutralizing activity against rMuV(JL5)-F/HN(BMV) Our data suggests that people who have neutralizing antibodies against MuV might be protected from infection by BMV