JOURNAL OF GENE MEDICINE
The Journal of Gene Medicine is a print and electronic journal that publishes articles on the science of gene transfer and its clinical applications. The Journal presents articles on all aspects of gene therapy including design and production of vectors, research into mechanisms underlying gene transfer, preclinical studies including animal models, developmental aspects (large scale production, toxicology) and clinical trials. Articles dealing with the methodological aspects of gene transfer in vivo, notably in the context of human studies, are particularly relevant to this journal.
| The Journal of Gene Medicine Exploring gene-deleted adenoviral vectors for delivery of short hairpin RNAs and reduction of hepatitis B virus infection in mice RNA interference based therapeutic approaches hold promise for the treatment of patients chronically infected with hepatitis B virus (HBV). To conquer HBV infection, long-term suppression of target transcripts in all hepatocytes without toxic effects may be required. The present study explored gene-deleted adenoviral vectors (GD-AdV) lacking all viral coding sequences for delivery of the previously described short hairpin RNA (shRNA) HBVU6no.2, which was demonstrated to result in post-transcriptional knock-down of HBV transcripts.We established conditions for shRNA delivery expressed from GD-AdV in vitro and in vivo and observed up to 96% shRNA-mediated knockdown of luciferase expressed in mouse liver. To investigate in vivo efficacy of HBVU6no.2 expressed from a GD-AdV, we explored a transient and a transgenic mouse model for HBV infection.We observed an up to 68% drop in serum HBV surface antigen (HBsAg) levels in the transient and the transgenic mouse model for HBV infection, respectively. Interestingly, we detected an up to 86% drop in HBsAg levels in both animal models after administration of a control GD-AdV encoding [beta]-galactosidase. In concordance with reduced serum HBsAg levels, we observed reduced HBV replication as demonstrated by Southern blot analysis of HBV genomes.The present study demonstrates that GD-AdV can be used against HBV infection but the design of DNA sequences including shRNAs contained in the vector and virus-host interactions during superinfection needs to be carefully considered. Copyright © 2008 John Wiley & Sons, Ltd. Prolonged gene silencing in hepatoma cells and primary hepatocytes after small interfering RNA delivery with biodegradable poly([beta]-amino esters) Small interfering (si)RNA mediated inhibition of oncogenes or viral genes may offer great opportunities for the treatment of several diseases such as hepatocellular carcinoma and viral hepatitis. However, the development of siRNAs as therapeutic agents strongly depends on the availability of safe and effective intracellular delivery systems. Poly([beta]-amino esters) (PbAEs) are, in contrast to many other cationic polymers evaluated in siRNA delivery, biodegradable into smaller, nontoxic molecules.We show for the first time that PbAE : siRNA complexes, containing 1,4-butanediol (PbAE1) or 1,6-hexanediol (PbAE2) diacrylate-based polymers, induced efficient gene silencing in both hepatoma cells and primary hepatocytes without causing significant cytotoxicity. Furthermore, carriers that slowly release the siRNA into the cytoplasm and hence induce a prolonged gene silencing are of major clinical interest, especially in fast dividing tumour cells. Therefore, we also studied the duration of gene silencing in the hepatoma cells and found that it was maintained for at least 5 days after siRNA delivery with PbAE2, the polymer with the slowest degradation kinetics.From the time-dependent cellular distribution of these PbAE : siRNA complexes, we suggest that the slowly degrading PbAE2 causes a sustained endosomal release of siRNA during a much longer period than PbAE1. This may support the hypothesis that the endosomal release mechanism of PbAE : siRNA complexes is based on an increase of osmotic pressure in the endosomal vesicles after polymer hydrolysis. In conclusion, our results show that both PbAEs, and especially PbAE2, open up new perspectives for the development of efficient biodegradable siRNA carriers suitable for clinical applications. Copyright © 2008 John Wiley & Sons, Ltd. Recent developments in adeno-associated virus vector technology Adeno-associated virus (AAV), a single-stranded DNA parvovirus, is emerging as one of the leading gene therapy vectors owing to its nonpathogenicity and low immunogenicity, stability and the potential to integrate site-specifically without known side-effects. A portfolio of recombinant AAV vector types has been developed with the aim of optimizing efficiency, specificity and thereby also the safety of in vitro and in vivo gene transfer. More and more information is now becoming available about the mechanism of AAV/host cell interaction improving the efficacy of recombinant AAV vector (rAAV) mediated gene delivery. This review summarizes the current knowledge of the infectious biology of AAV, provides an overview of the latest developments in the field of AAV vector technology and discusses remaining challenges. Copyright © 2008 John Wiley & Sons, Ltd. Effective transduction by self-complementary adeno-associated viruses of human dendritic cells with no alteration of their natural characteristics Effective gene delivery techniques are required to genetically manipulate dendritic cells (DCs). We therefore investigated the feasibility of using various self-complementary recombinant adeno-associated virus (scAAV) serotypes to deliver genes to human DCs.Monocytes isolated from healthy volunteers were differentiated to immature DCs (iDC) by incubation with interleukin (IL)-4 and granulocyte macrophage colony-stimulating factor. The iDCs were transduced with scAAV1, 2, 3, 4, 5, 6 or 8 at various multiplicities of infection (MOIs). Transduction efficiency (TE), cell viability and functional characteristics of the transduced DCs were evaluated.TE of scAAV was three-fold greater than TE of conventional recombinant adeno-associated virus with a single-stranded genome. The TEs of scAAV2, 5, and 6 were much higher than those of the other scAAVs; at 1000 MOI, the TEs were 22.2% ± 9.5%, 27.0% ± 8.8% and 28.4% ± 6.0%, respectively. Exposure of iDCs to 5000 MOI of these viruses increased their TEs, leading to the transduction of nearly the entire DC population. In addition, gene transfer by scAAV did not cause any cytotoxicity. Flow cytometric analysis of scAAV-transduced DCs showed no changes in surface marker profiles. Moreover, transduced cells maintained their functional properties, as represented by active antigen uptake. These cells could efficiently differentiate into mature DCs, as shown by their release of IL-12, the substantial loss of antigen-uptake activity, and the ability of T-cell stimulation.These findings strongly indicate that scAAVs, especially subtypes 2, 5 and 6, hold a promising potential as gene delivery tools in human DCs. Copyright © 2008 John Wiley & Sons, Ltd. The effect of gene therapy using CTLA4Ig/silica-nanoparticles on canine experimental autoimmune thyroiditis The present study aimed to determine the effect of canine CTLA4Ig on canine autoimmune thyroiditis. In a previous study, we established a canine model of autoimmune thyroiditis by immunizing normal dogs with bovine thyroglobulin. An in vitro study using recombinant CTLA4Ig revealed that this protein can inhibit the expression of Th1-type cytokines and the pro-inflammatory cytokines tested.As a result of the in vitro study, we constructed therapeutic CTLA4Ig/silica-nanoparticles and applied them to the treatment of experimentally induced canine autoimmune thyroiditis.Gene therapy resulted in significant reductions in anti-canine-thyroglobulin autoantibody titer, anti-T4 antibody titer and T-cell proliferation against thyroglobulin and in the mRNA expressions of interleukin-18 in fresh peripheral blood mononuclear cells (PBMC) from all dogs. There was also a significant reduction compared to day 0 in tumor necrosis factor-[alpha] and interferon-[gamma] levels in the supernatant from cultured PBMC.The CTLA4Ig-induced suppression of Th1 cytokines is relatively more significant than it appears because autoimmune thyroiditis is a Th1-polarized disease. Thus, CTLA4Ig can improve Th1/Th2 cytokine balance in autoimmune thyroiditis by downregulating Th1 cytokines. Copyright © 2008 John Wiley & Sons, Ltd. Gene delivery of indoleamine 2,3-dioxygenase prolongs cardiac allograft survival by shaping the types of T-cell responses We investigated the hypothesis that overexpression of indoleamine 2,3-dioxygenase (IDO) by a cardiac allograft may result in a survival advantage of the allograft by creating a tolerogenic microenvironment.An adenoviral vector encoding for murine IDO cDNA (AdIDO) was transfected into murine allogeneic cardiac allografts, and transplantation was performed for evaluation of the effects of local AdIDO transfection on allograft survival. Intragraft IDO expression and lymphocytes infiltration were measured by immunohistochemical and histological analysis. Quantitative polymerase chain reaction assays, mixed lymphocyte reaction and flow cytometric analysis were employed to determine the expression of mRNA for Foxp3, IDO, pro-inflammatory cytokines, allogeneic T-cell proliferation and the proportion of CD4+CD25+Foxp3+ regulatory T cells (Tregs) from graft-infiltrating lymphocytes and splenocytes of recipients, respectively.Cardiac allografts transfected with AdIDO showed a significant prolonged survival compared to the control groups. Hearts treated with AdIDO exhibited considerable up-regulation of IDO expression, whereas contained significantly reduced transcript levels for interleukin (IL)-2, interferon-[gamma] and IL-17. These T cells isolated from allografts pre-treated with AdIDO displayed a dramatic reduction of proliferation capacity to alloantigen stimuli and had a significant higher proportion of Tregs compared to the control, as demonstrated by an increase of Foxp3 expression in allografts pre-treated with AdIDO compared to control groups.Overexpression of IDO significantly delays cardiac allograft acute rejection by shaping the types of T-cell responses elicited by alloantigen stimuli. Copyright © 2008 John Wiley & Sons, Ltd. Treatment of autoimmune ovarian disease by co-administration with mouse zona pellucida protein 3 and DNA vaccine through induction of adaptive regulatory T cells Autoimmune ovarian disease (AOD) caused by auto-reactive T cells is considered a major reason for human premature ovarian failure, which affects 5% of women worldwide.To develop an effective treatment for AOD, we showed that the co-administration of mouse zona pellucida protein 3 (mZP3) protein and DNA vaccine encoding the mZP3 was able to meliorate AOD in an AOD murine model induced by the mZP3. We observed that established AOD in mice reverted to a normal ovarian morphology without notable T-cell infiltration in the co-administrated group; whereas mice in the control groups developed severe AOD. The amelioration appears to be antigen specific because other co-administration combinations failed to reverse AOD and correlates with significant reductions of pathogenic T-cell responses and productions of tumor necrosis factor-[alpha] and interferon-[gamma]. Furthermore, the melioration is apparently associated with the induction of mZP3 specific regulatory T cells that exhibit a phenotypic CD4+CD25-FoxP3+IL-10+ in the co-administrated group, which can be transferred to reverse AOD in vivo.Thus, co-administration of mZP3 DNA and protein vaccines can be used to treat established AOD, and may provide a novel immunotherapy strategy to treat other autoimmune diseases. Copyright © 2008 John Wiley & Sons, Ltd. Physical characterization and in vivo evaluation of poloxamer-based DNA vaccine formulations Plasmid DNA (pDNA) vaccines have generated significant interest for the prevention or treatment of infectious diseases. Broader applications may benefit from the identification of safe and potent vaccine adjuvants. This report describes the development of a novel polymer-based formulation to enhance the immunogenicity of pDNA-based vaccines.Plasmid DNA was formulated with a nonionic block copolymer, poloxamer CRL1005, and the cationic surfactant benzalkonium chloride (BAK) to produce a thermodynamically stable, self-assembling system. The influence of parameters such as polymer concentration and BAK composition on the immune responses was evaluated in mice vaccinated with pDNA encoding influenza nucleoprotein.At concentrations of 7.5 mg/ml CRL1005, 0.3 mM BAK and 5 mg/ml pDNA, CRL1005/BAK/pDNA particles had a mean diameter of 261 ± 0.2 nm and a surface charge of - 11.6 ± 0.9 mV. The negative surface charge and atomic force microscopy images suggested that pDNA binds to BAK adsorbed to the surface of poloxamer particles. The CRL1005/BAK/pDNA formulation significantly enhanced antigen-specific cellular and humoral immune responses, and increased transgene levels in muscle and serum. The complexity of the formulation was reduced by replacing the commercial BAK, which is a mixture of four alkyl chains, with a C14 BAK homolog. The substitution yielded an analytically preferable formulation with equivalent physical characteristics and immunogenicity.The results suggest that the CRL1005/BAK/pDNA formulation may enhance immunogenicity by improving the delivery of pDNA-based vaccines. This formulation is currently being evaluated for the prevention of CMV-associated disease in a phase 2 clinical trial. Copyright © 2008 John Wiley & Sons, Ltd. Long-term follow up of initial clinical cases with NF-[kappa]B decoy oligodeoxynucleotide transfection at the site of coronary stenting An essential transcription factor for inflammation, nuclear factor-kappa B (NF-[kappa]B), plays a pivotal role for restenosis after percutaneous coronary intervention (PCI). To evaluate the safety and effectiveness of NF-[kappa]B decoy oligodeoxynucleotides (ODN) to prevent restenosis, we initiated an open-label phase I/IIa clinical trial.Seventeen patients who were suffering from angina with organic coronary stenosis were treated with NF-[kappa]B decoy ODN after PCI using bare metal stents.Although the average coronary stenosis was 90.8 ± 7.0% before the stent implantation, the stenosis improved to 1.4 ± 5.9% after the intervention. Serum MCP-1 levels were significantly suppressed in NF-[kappa]B decoy ODN treated patients compared to those in non-treated patients on day 3 after the PCI. Ticlopidine treatment was employed, since clopidogrel was not launched in Japan. Six months after the PCI and decoy ODN transfection, significant restenosis was found in only 1 of the 17 patients, and the average restenosis rate was 39.6 ± 22.3%. No in-stent thrombosis was found and no significant systemic adverse effect occurred in any of the patients in this observation period.These results suggest the clinical usefulness and safety of the NF-[kappa]B decoy ODN transfer after PCI, although further placebo control trials are necessary. Copyright © 2008 John Wiley & Sons, Ltd. Secretion of mouse growth hormone by transduced primary human keratinocytes: prospects for an animal model of cutaneous gene therapy Keratinocytes are a very attractive vehicle for ex vivo gene transfer and systemic delivery because proteins secreted by these cells may reach the circulation via a mechanism that mimics the natural process.An efficient retroviral vector (LXSN) encoding the mouse growth hormone gene (mGH) was used to transduce primary human keratinocytes. Organotypic raft cultures were prepared with these genetically modified keratinocytes and were grafted onto immunodeficient dwarf mice (lit/scid).Transduced keratinocytes presented a high and stable in vitro secretion level of up to 11 µg mGH/106cells/day. Conventional epidermal sheets made with these genetically modified keratinocytes, however, showed a drop in secretion rates of > 80% due to detachment of the epithelium from its substratum. Substitution of conventional grafting methodologies with organotypic raft cultures completely overcame this problem. The stable long-term grafting of such cultures onto lit/scid mice could be followed for more than 4 months, and a significant weight increase over the control group was observed in the first 40 days. Circulating mGH levels revealed a peak of 21 ng/ml just 1 h after grafting but, unfortunately, these levels rapidly fell to baseline values.mGH-secreting primary human keratinocytes presented the highest in vitro expression and peak circulatory levels reported to date for a form of GH with this type of cells. Together with previous data showing that excised implants can recover a remarkable fraction of their original in vitro mGH secretion efficiency in culture, the factors that might still hamper the success of this promising model of cutaneous gene therapy are discussed. Copyright © 2008 John Wiley & Sons, Ltd. The cyclo-oxygenase 2 promoter is induced in nontarget cells following adenovirus infection, but an AU-rich 3[prime]-untranslated region destabilization element can increase specificity Cyclo-oxygenase 2 (Cox-2) is expressed in many types of tumors, but typically undetectable in normal tissues. However, Cox-2 is known to be induced following infection by many microbial agents, which might threaten the tumor selectivity of the Cox-2 promoter in the context of virotherapy or viral gene delivery. Cox-2 expression is regulated in part post-transcriptionally by stimulation or inhibition of mRNA degradation by 3[prime]-untranslated region (3[prime]-UTR) AU-rich elements. In the present study, we investigated the induction of the Cox-2 promoter both in normal and tumor cells after adenovirus infection and explored the utility of AU-rich elements for regaining promoter selectivity.Nontumor and tumor cells were transfected in vitro and in vivo with plasmids containing the Cox-2 or cytomegalovirus immediate early promoter driving luciferase (with or without 3[prime]-UTR elements) followed by adenoviral infection. Selectivity and activity of the promoters and 3[prime]-UTR elements were analysed by luciferase assay and in-vivo imaging.The Cox-2 promoter was induced in both normal and tumor cells following infection with E1 containing replicative adenoviruses but not in the absence of E1. Utilization of AU-rich elements counteracted promoter induction in vitro and in vivo in nonmalignant cells but not in cancer cells, thus increasing the selectivity of the approach ten-fold without loss of potency.Adenoviral infection induces the Cox-2 promoter in normal and tumor cells, which might compromise specificity of the promoter. Utilization of AU-rich destabilization elements can rescue the tumor selectivity of the promoter. Copyright © 2008 John Wiley & Sons, Ltd. Increase Search Engine Traffic |
