scholarly journals Evaluation of Transduction Properties of an Adenovirus Vector in Neonatal Mice

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Shunsuke Iizuka ◽  
Fuminori Sakurai ◽  
Kahori Shimizu ◽  
Kazuo Ohashi ◽  
Shin-ichiro Nakamura ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Transgene Expression ◽  
Adenovirus Vector ◽  
Firefly Luciferase ◽  
Luciferase Expression ◽  
Cmv Promoter ◽  
Neonatal Mice ◽  
Neonatal Heart ◽  
Neonatal Liver ◽  
Neonates And Infants

In gene therapy for congenital disorders, treatments during neonate and infant stages are promising. Replication-incompetent adenovirus (Ad) vectors have been used in gene therapy studies of genetic disorders; however, the transduction properties of Ad vectors in neonates and infants have not been fully examined. Accordingly, this study examined the properties of Ad vector-mediated transduction in neonatal mice. A first-generation Ad vector containing a cytomegalovirus (CMV) promoter-driven luciferase expression cassette was administered to neonatal mice on the second day of lifeviaretro-orbital sinus. The highest Ad vector genome copy numbers and transgene expression were found in the neonatal liver. The neonatal heart exhibited the second highest levels of transgene expression among the organs examined. There was an approximately 1500-fold difference in the transgene expression levels between the adult liver and heart, while the neonatal liver exhibited only an approximately 30-fold higher level of transgene expression than the neonatal heart. A liver-specific promoter for firefly luciferase expression conferred a more than 100-fold higher luciferase expression in the liver relative to the other organs. No apparent hepatotoxicity was observed in neonatal mice following Ad vector administration. These findings should provide valuable information for gene therapy using Ad vectors in neonates and infants.

scholarly journals Polyinosinic acid enhances delivery of adenovirus vectors in vivo by preventing sequestration in liver macrophages

2008 ◽  
Vol 89 (5) ◽  
pp. 1097-1105 ◽  
Author(s):  
Hidde J. Haisma ◽  
Jan A. A. M. Kamps ◽  
Gera K. Kamps ◽  
Josee A. Plantinga ◽  
Marianne G. Rots ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Kupffer Cells ◽  
Transgene Expression ◽  
Liver Toxicity ◽  
Viral Vector ◽  
Adenovirus Vector ◽  
Liver Macrophages ◽  
Polyinosinic Acid

Adenovirus is among the preferred vectors for gene therapy because of its superior in vivo gene-transfer efficiency. However, upon systemic administration, adenovirus is preferentially sequestered by the liver, resulting in reduced adenovirus-mediated transgene expression in targeted tissues. In the liver, Kupffer cells are responsible for adenovirus degradation and contribute to the inflammatory response. As scavenger receptors present on Kupffer cells are responsible for the elimination of blood-borne pathogens, we investigated the possible implication of these receptors in the clearance of the adenovirus vector. Polyinosinic acid [poly(I)], a scavenger receptor A ligand, was analysed for its capability to inhibit adenovirus uptake specifically in macrophages. In in vitro studies, the addition of poly(I) before virus infection resulted in a specific inhibition of adenovirus-induced gene expression in a J774 macrophage cell line and in primary Kupffer cells. In in vivo experiments, pre-administration of poly(I) caused a 10-fold transient increase in the number of adenovirus particles circulating in the blood. As a consequence, transgene expression levels measured in different tissues were enhanced (by 5- to 15-fold) compared with those in animals that did not receive poly(I). Finally, necrosis of Kupffer cells, which normally occurs as a consequence of systemic adenovirus administration, was prevented by the use of poly(I). No toxicity, as measured by liver-enzyme levels, was observed after poly(I) treatment. From our data, we conclude that poly(I) can prevent adenovirus sequestration by liver macrophages. These results imply that, by inhibiting adenovirus uptake by Kupffer cells, it is possible to reduce the dose of the viral vector to diminish the liver-toxicity effect and to improve the level of transgene expression in target tissues. In systemic gene-therapy applications, this will have great impact on the development of targeted adenoviral vectors.

scholarly journals Small Molecule Inhibition of the Innate Immune Response Increases Transgene Expression

2018 ◽  
Author(s):  
Kyle Spivack ◽  
Christine Muzzelo ◽  
Christopher Neely ◽  
Julia Vanzelli ◽  
Evan Kurt ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Immune Response ◽  
Cell Proliferation ◽  
Innate Immune Response ◽  
Small Molecule ◽  
Transgene Expression ◽  
Defense Mechanism ◽  
Innate Immune ◽  
Luciferase Expression ◽  
Mcf 7

AbstractForeign molecules like plasmid DNA trigger a complex and potent innate immune response comprised of highly redundant signal transduction cascades that result in the activation of transcription factors and the production of inflammatory cytokines. Unfortunately, this defense mechanism can hinder gene therapy by inhibiting transgene expression. The goal of this study was to increase transgene expression by inhibiting key components of the innate immune response (β-catenin, NF-κB/AP1, TBK1, TLR9, and p38 MAPK) with small molecule inhibitors (iCRT-14, curcumin, BX-795, E6446, and VX-702 respectively). The effects of each drug on transgene (luciferase) expression, inflammatory cytokine (IL-6) levels, and cell viability were quantified in prostate (PC3), breast (MCF-7), and murine bladder (MB49) cancer cell lines. The β-catenin inhibitor iCRT-14 (1 μM) provided the highest enhancement of 35.5 ± 19-fold in MCF-7 cells, while the other inhibitors increased transgene expression at a more modest level (2-9 fold). The optimal concentrations of iCRT-14, curcumin, and VX-702 showed no significant effect on cell proliferation; however, optimal concentrations of BX-795 and E6446 did significantly reduce cell proliferation. Nonetheless, inhibition of the innate immune response by iCRT-14 and curcumin was confirmed by a concomitant decrease in IL-6 production in PC3 cells. These results demonstrate that these inhibitors can improve gene therapy by preventing an inflammatory innate immune response.

scholarly journals Hepatic DR5 Induces Apoptosis and Limits Adenovirus Gene Therapy Product Expression in the Liver

2002 ◽  
Vol 76 (11) ◽  
pp. 5692-5700 ◽  
Author(s):  
Huang-Ge Zhang ◽  
Jinfu Xie ◽  
Liang Xu ◽  
Pingar Yang ◽  
Xin Xu ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Immune Response ◽  
Transgene Expression ◽  
Cell Activation ◽  
Nk Cell ◽  
Death Domain ◽  
Activated T Cells ◽  
Tnf Α ◽  
Product Expression ◽  
Ifn Γ

ABSTRACT A major limitation of adenovirus (Ad) gene therapy product expression in the liver is subsequent elimination of the hepatocytes expressing the gene therapy product. This elimination is caused by both necrosis and apoptosis related to the innate and cell-mediated immune response to the Ad. Apoptosis of hepatocytes can be induced by the innate immune response by signaling through death domain receptors on hepatocytes including the tumor necrosis factor alpha (TNF-α) receptor (TNFR), Fas, and death domain receptors DR4 and DR5. We have previously shown that blocking signaling through TNFR enhances and prolongs gene therapy product expression in the liver. In the present study, we constructed an Ad that produces a soluble DR5-Fc (AdsDR5), which is capable of neutralizing TNF-related apoptosis-inducing ligand (TRAIL). AdsDR5 prevents TRAIL-mediated apoptosis of CD3-activated T cells and decreases hepatocyte apoptosis after AdCMVLacZ administration and enhances the level and duration of lacZ transgene expression in the liver. In addition to blocking TRAIL and directly inhibiting apoptosis, AdsDR5 decreases production of gamma interferon (IFN-γ) and TNF-α and decreases NK cell activation, all of which limit Ad-mediated transgene expression in the liver. These results indicate that (i) AdsDR5 produces a DR5-Fc capable of neutralizing TRAIL, (ii) AdsDR5 can reduce activation of NK cells and reduce induction of IFN-γ and TNF-α after Ad administration, and (iii) administration of AdsDR5 can enhance Ad gene therapy in the liver.

scholarly journals Foamy Virus Vector Carries a Strong Insulator in Its Long Terminal Repeat Which Reduces Its Genotoxic Potential

2017 ◽  
Vol 92 (1) ◽  
Author(s):  
Michael Aaron Goodman ◽  
Paritha Arumugam ◽  
Devin Marie Pillis ◽  
Anastacia Loberg ◽  
Mohammed Nasimuzzaman ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Long Terminal Repeat ◽  
Transgene Expression ◽  
Viral Vectors ◽  
Foamy Virus ◽  
Terminal Repeat ◽  
Genotoxic Potential ◽  
Binding Factor ◽  
Activation Assay ◽  
Lentivirus Vectors

ABSTRACTStrong viral enhancers in gammaretrovirus vectors have caused cellular proto-oncogene activation and leukemia, necessitating the use of cellular promoters in “enhancerless” self-inactivating integrating vectors. However, cellular promoters result in relatively low transgene expression, often leading to inadequate disease phenotype correction. Vectors derived from foamy virus, a nonpathogenic retrovirus, show higher preference for nongenic integrations than gammaretroviruses/lentiviruses and preferential integration near transcriptional start sites, like gammaretroviruses. We found that strong viral enhancers/promoters placed in foamy viral vectors caused extremely low immortalization of primary mouse hematopoietic stem/progenitor cells compared to analogous gammaretrovirus/lentivirus vectors carrying the same enhancers/promoters, an effect not explained solely by foamy virus' modest insertional site preference for nongenic regions compared to gammaretrovirus/lentivirus vectors. Using CRISPR/Cas9-mediated targeted insertion of analogous proviral sequences into theLMO2gene and then measuringLMO2expression, we demonstrate a sequence-specific effect of foamy virus, independent of insertional bias, contributing to reduced genotoxicity. We show that this effect is mediated by a 36-bp insulator located in the foamy virus long terminal repeat (LTR) that has high-affinity binding to the CCCTC-binding factor. Using our LMO2 activation assay,LMO2expression was significantly increased when this insulator was removed from foamy virus and significantly reduced when the insulator was inserted into the lentiviral LTR. Our results elucidate a mechanism underlying the low genotoxicity of foamy virus, identify a novel insulator, and support the use of foamy virus as a vector for gene therapy, especially when strong enhancers/promoters are required.IMPORTANCEUnderstanding the genotoxic potential of viral vectors is important in designing safe and efficacious vectors for gene therapy. Self-inactivating vectors devoid of viral long-terminal-repeat enhancers have proven safe; however, transgene expression from cellular promoters is often insufficient for full phenotypic correction. Foamy virus is an attractive vector for gene therapy. We found foamy virus vectors to be remarkably less genotoxic, well below what was expected from their integration site preferences. We demonstrate that the foamy virus long terminal repeats contain an insulator element that binds CCCTC-binding factor and reduces its insertional genotoxicity. Our study elucidates a mechanism behind the low genotoxic potential of foamy virus, identifies a unique insulator, and supports the use of foamy virus as a vector for gene therapy.

Optimization and Internalization Mechanisms of PEGylated Adenovirus Vector with Targeting Peptide for Cancer Gene Therapy

2012 ◽  
Vol 13 (8) ◽  
pp. 2402-2409 ◽  
Author(s):  
Xing-Lei Yao ◽  
Yasuo Yoshioka ◽  
Gui-Xin Ruan ◽  
Yu-Zhe Chen ◽  
Hiroyuki Mizuguchi ◽  
...  
Keyword(s):  
Gene Therapy ◽  
Adenovirus Vector ◽  
Cancer Gene Therapy ◽  
Cancer Gene ◽  
Targeting Peptide

scholarly journals Measurement of Effects of Antibiotics in Bioluminescent Staphylococcus aureus RN4220

2001 ◽  
Vol 45 (12) ◽  
pp. 3456-3461 ◽  
Author(s):  
Mervi Tenhami ◽  
Kaisa Hakkila ◽  
Matti Karp
Keyword(s):  
Staphylococcus Aureus ◽  
High Throughput Screening ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Light Emission ◽  
Detection System ◽  
Firefly Luciferase ◽  
Luciferase Reporter ◽  
Luciferase Expression ◽  
Luciferase Reporter Gene

ABSTRACT The spread of antibiotic resistance among pathogenic bacteria is a serious threat to humans and animals. Therefore, unnecessary use should be minimized, and new antimicrobial agents with novel mechanisms of action are needed. We have developed an efficient method for measuring the action of antibiotics which is applied to a gram-positive strain,Staphylococcus aureus RN4220. The method utilizes the firefly luciferase reporter gene coupled to the metal-induciblecadA promoter in a plasmid, pTOO24. Correctly timed induction by micromolar concentrations of antimonite rapidly triggers the luciferase gene transcription and translation. This sensitizes the detection system to the action of antibiotics, and especially for transcriptional and translational inhibitors. We show the results for 11 model antibiotics with the present approach and compare them to an analytical setup with a strain where luciferase expression is under the regulation of a constitutive promoter giving only a report of metabolic inhibition. The measurement of light emission from intact living cells is shown to correlate extremely well (r = 0.99) with the conventional overnight growth inhibition measurement. Four of the antibiotics were within a 20% concentration range and four were within a 60% concentration range of the drugs tested. This approach shortens the assay time needed, and it can be performed in 1 to 4 h, depending on the sensitivity needed. Furthermore, the assay can be automatized for high-throughput screening by the pharmaceutical industry.

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