Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001486 (Adenovirus)
 3,125 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The human transmembrane fms-like receptor tyrosine kinase Flt-1 is one of the receptors for vascular endothelial growth factor, a growth factor which induces endothelial proliferation and vascular permeability. Flt-1 is expressed specifically in endothelium and is likely to play a role in tumor angiogenesis and embryonic vascularization. To elucidate the molecular basis for the endothelial specific expression of Flt-1, the promoter region has been isolated and functionally characterized. The promoter region contains a TATA box, a GC-rich region, and putative transcription factor binding elements such as cAMP response element binding protein/activating transcription factor (CREB/ATF) and ets. Adenovirus-mediated transient expression of the flt-1 promoter/luciferase fusion gene in endothelial cells and other cell types demonstrated that a 1-kilobase fragment of the 5'-flanking region of flt-1 is involved in the endothelial-specific expression. A CREB/ATF element was found to be essential for basal transcription of the flt-1 expression. In addition, we also showed that the first intron negatively regulates flt-1 promoter activity. The flt-1 promoter will be useful in functional studies on the regulation of endothelial-specific gene expression and also as a tool in targeting the expression of exogenously introduced genes to the endothelium.
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PMID:A novel promoter for vascular endothelial growth factor receptor (flt-1) that confers endothelial-specific gene expression. 749 71

To evaluate the role of cell-mediated immunity during gene transfer to the respiratory epithelium, the time course of luciferase activity was assessed after intratracheal administration of Av1Luc1, an E1a-E3-deleted adenoviral (Ad5) vector expressing firefly luciferase, to FVB/N, BALB/c and BALB/c-nu/nu adult mice. Adenovirus-mediated luciferase activity was rapidly lost from the respiratory tract between 2 and 14 days after treatment of both FVB/N and BALB/c wild-type mice. In the wild-type mice, loss of luciferase activity was associated with an early inflammatory response consisting of infiltration with macrophages and polymorphonuclear leukocytes and a more prolonged response characterized by lymphocytic infiltration. In the immune-deficient nu/nu mice, luciferase activity was maintained at higher levels than in immune-competent mice after exposure to virus and was associated with a distinct pattern of inflammation, consisting primarily of macrophages and polymorphonuclear cells but lacking the lymphocytic infiltrates typical of the inflammation in wild-type mice. Adenoviral DNA was rapidly cleared from the lungs of both nu/nu and wild-type mice. Markedly increased expression of proliferating cell nuclear antigen (PCNA) was observed in bronchiolar and alveolar epithelial cells and in inflammatory cells after exposure to Av1LUc1. The proliferative response of the respiratory epithelium was more extensive and persistent in wild-type than in nu/nu mice. To assess further the impact of the immune system on adenovirus-mediated gene expression, cotton rats treated with cyclosporin A or dexamethasone were exposed to Av1Luc1. Both agents decreased lung inflammation and significantly increased lung luciferase activity. The loss of lung luciferase activity is dependent, in part, on the immune-mediated clearance of respiratory epithelial cells, which may limit the extent and duration of gene expression with recombinant adenoviral vectors.
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PMID:Persistence of replication-deficient adenovirus-mediated gene transfer in lungs of immune-deficient (nu/nu) mice. 761 2

Apolipoprotein E (apoE)-deficient mice develop marked hyperlipidemia as well as atherosclerosis and thus are an excellent animal model for evaluating the potential for gene therapy in human genetic dyslipoproteinemias. Recombinant adenovirus containing either human apoE (rAdv.apoE) or the reporter gene luciferase (rAdv.luc) were generated and infused intravenously in apoE-deficient mice with preinfusion plasma total cholesterol of 644 +/- 149 mg/dl an cholesterol rich VLDL/IDL. After a single infusion of rAdv.apoE, plasma concentrations of human apoE ranging from 1.5 to 650 mg/dl were achieved. Adenovirus-mediated apoE replacement resulted in normalization of the lipid and lipoprotein profile with markedly decreased total cholesterol (103 +/- 18mg/dl), VLDL, IDL, and LDL, as well as increased HDL. Measurement of aortic atherosclerosis 1 mo after adenoviral infusion demonstrated a marked reduction in the mean lesion area of mice infused with rAdv.apoE (58 +/- 8 x 10(3) microns2) when compared with control mice infused with rAdv.luc (161 +/- 10 x 10(3) microns2; P < 0.0001). Thus, apoE expression for 4 wk was sufficient to markedly reduce atherosclerosis, demonstrating the feasibility of gene therapy for correction of genetic hyperlipidemias resulting in atherosclerosis. The combined use of adenovirus vectors and the apoE-deficient mouse represents a new in vivo approach that will permit rapid screening of candidate genes for the prevention of atherosclerosis.
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PMID:Apolipoprotein E deficiency in mice: gene replacement and prevention of atherosclerosis using adenovirus vectors. 765 31

The safety of replication-defective viruses used as vectors is based on the deletion of essential gene(s). Adenovirus vector safety relies on the deletion of the E1A/E1B region. This region encodes the immediate-early proteins that trans activate all other early regions, so DNA replication in these deletion mutants is dramatically reduced. We have previously shown that E1A deletion is efficient in vivo and significantly reduces the dissemination of adenovirus in mice and cotton rats. However, the pattern of dissemination of E1A-deleted and wild-type viruses showed that both could be localized in the same tissues, thus involving a theoretical risk of phenotypic complementation if a recipient of E1A-deleted adenovirus is infected after adenovirus-mediated gene therapy by a wild-type adenovirus. In this report, we show that complementation can be evidenced in vitro in Vero cells infected with E1A/E1B-defective adenovirus vectors expressing reporter genes (either beta-galactosidase or luciferase), passaged three times until no infectious virus can be recovered by plating on 293 cells, and then infected with wild-type adenovirus 5. A mixed virus population was maintained at a stable state for at least 10 passages. In contrast, no evidence of complementation was found in cotton rats inoculated intravenously or intramuscularly with Ad-beta-gal-nls and Ad-luc and infected 24 h later intranasally with wild-type adenovirus 5. No increase in the level of luciferase expression was found in these animals, compared with that in controls, nor was any viral population expressing beta-galactosidase or luciferase isolated from various organs or any animal excretion or secretion.
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PMID:Lack of evidence of phenotypic complementation of E1A/E1B-deleted adenovirus type 5 upon superinfection by wild-type virus in the cotton rat. 766 53

Adenovirus (Ad) vectors have been used extensively to obtain high-level expression of foreign genes in mammalian cells and are currently being studied for use as live viral-vectored vaccines and as gene transfer vectors for gene therapy. Many Ad recombinants have been generated that express foreign genes inserted in early region 3 (E3); however, little has been done to study the importance for gene expression of regulatory sequences flanking the gene. We have generated a series of Ad5 helper-independent vectors that contain the firefly luciferase gene or the bacterial beta-galactosidase gene (LacZ) with or without simian virus 40 (SV40) regulatory sequences, combined with E3 deletions of 1.88 or 2.69 kb. The greatest levels of luciferase expression were obtained with a vector containing the luciferase gene under the control of the SV40 promoter and polyadenylation signal inserted in a 1.88-kb E3 deletion. In contrast, LacZ expression was highest with a vector containing the LacZ gene with just the SV40 polyadenylation sequence combined with a 1.88-kb E3 deletion. It was also observed that regardless of the SV40 sequences flanking the reporter gene or the E3 deletion used, expression from the luciferase recombinants was dependent on viral DNA replication, whereas expression from the LacZ recombinants was only partially reduced when DNA replication was blocked. Analyses of RNA by dot blot hybridizations revealed that the levels of reporter gene-specific mRNA for various vectors in each series did not vary significantly. These results indicate that the kinetics and efficiency of expression of genes inserted into the E3 region, in nonconditional helper-independent vectors, may be more strongly dependent on the sequences in the foreign gene insert itself than on flanking regulatory sequences such as those used here, derived from SV40.
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PMID:Foreign gene expression by human adenovirus type 5-based vectors studied using firefly luciferase and bacterial beta-galactosidase genes as reporters. 779 76

Ligand-mediated approaches to gene transfer offer an alternative to viral vectors for both in vivo and in vitro applications. Although a significant percentage of the plasmid-based DNA complex is lost to lysosomal degradation following receptor-mediated endocytosis, simultaneous infection with adenovirus has been shown to increase the level of transgene expression [Curiel, Agarwal, Wagner and Cotten (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 8850-8854; Wagner, Zatloukal, Cotten, Kirlappos, Mechtler, Curiel and Birnstiel (1992) Proc. Natl. Acad. Sci. U.S.A. 89, 6099-6103]. In this study we describe an adenovirus-based ligand complex where the plasmid DNA, polycation-ligand conjugate and adenovirus are contained within a single particle structure. At the core of the transfection particle is a replication-defective recombinant adenovirus encoding a cDNA minigene for human placenta alkaline phosphatase that was chemically modified with poly(L-lysine) (Ad-pLys). Electron microscopy of an adenovirus-based ligand complex formed by successively adding plasmid DNA and an asialo-orosomucoid-poly(L-lysine) conjugate to Ad-pLys revealed structures that appeared as intact viral particles coated with a dense biomolecular layer. Adenovirus-based ligand complexes containing either a luciferase or beta-galactosidase reporter plasmid were shown to efficiently deliver the plasmid transgene to cells that express the hepatic asialoglycoprotein receptor. Furthermore, the poly(L-lysine) modification greatly reduced the infectivity potential of the virus without causing a concomitant loss of augmented gene transfer. As an alternative to infectious virions, incomplete products of viral assembly were also considered as a source for endosomalytic activity. However, these defective virions were unable to significantly enhance plasmid transgene delivery.
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PMID:Biochemical and functional analysis of an adenovirus-based ligand complex for gene transfer. 816 59

Studies of the regulation of androgen synthesis in steroidogenic cells have focused on both transcriptional and post-translational regulation of the proteins that catalyze these reactions: the P450c17 that catalyzes the production of DHEA or androstenedione in consecutive hydroxylase and lyase activities, and the 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) that catalyzes the conversion of androstenedione to testosterone. Our studies of the regulation of the CYP17 lyase activity at the molecular level have utilized species- and tissue-specific differences to identify target regulatory sequences. Adenovirus infection of rat CYP17 promoter/luciferase reporter gene constructs in primary cultures of rat adrenal and rat Leydig cells revealed a rat-specific domain between-1 and -108 bp that cause inhibition of both basal and cAMP-induced CYP17 transcription in the adrenal, but not the Leydig cell. In contrast, similar promoter constructs from other species exhibited substantial cAMP-induced transcriptional activity in the rat adrenal. Mutagenesis of the conserved region of the rat and human proteins reveals significant differences in the amino acid domains required for hydroxylase and lyase activities within and between the two species, consistent with their differential regulation of lyase activity. The 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) reaction requires a viable glucose transporter system for optimal activity, and a high-energy phosphate was discovered to be the requisite product of glucose metabolism in 17 beta-HSD activation. These studies have provided insight into potential mechanisms of control of androgen synthesis in the late steroidogenic pathway, at the transcriptional and post-translational levels.
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PMID:Regulation of androgen synthesis: the late steroidogenic pathway. 902 27

Targeted gene delivery is essential for gene therapy involving in vivo gene transfer. In the present study we analyzed the efficiency and tissue-specificity of gene transfer into the liver with recombinant adenoviruses. Adenovirus vectors carrying the E. coli lacZ gene (Ad.RSV.beta-gal) and the firefly luciferase gene (AdCMV-luc) as reporters were administered to the liver of adult Wistar rats, either via infusion into the portal vein (intraportal infusion; IPI) or via perfusion of the vascularity isolated liver (isolated liver perfusion; ILP). Ex vivo liver perfusion experiments with Ad.RSV. beta-gal were used to optimize the conditions for hepatic gene transfer. Ex vivo perfusion of rat livers with 2 x 10(9) plaque forming units (p.f.u) Ad RSV.beta-gal was sufficient to infect about 20% of the liver parenchymal cells. Perfusion with chelating agents (1 mM EGTA, or 2 mM EDTA) prior to the administration of the vector increased the efficiency to at least 40%. Similar efficiencies were obtained in experiments with liver lobes of Rhesus monkeys. In vivo administration of AdCMV-luc via ILP resulted in a significantly more efficient (P = 0.028) and also more reproducible gene transfer when compared to IPI. Although detectable in both groups, extrahepatic luciferase expression was considerably reduced in the ILP group. Our data demonstrate that IPL can be used for efficient and reproducible liver-specific gene delivery. Therefore, we think that the perfusion of vascularly isolated organs is useful as a modality for the tissue-specific administration of recombinant adenovirus vectors.
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PMID:Isolated-organ perfusion for local gene delivery: efficient adenovirus-mediated gene transfer into the liver. 906 96

Lipoprotein lipase (LPL) is the rate-limiting enzyme for the hydrolysis of triglyceride-rich lipoproteins. We tested the efficacy of adenovirus-mediated gene transfer of LPL as treatment of experimental hyperlipidemias associated with apolipoprotein (apoE) deficiency (apoE-/-) and low-density lipoprotein receptor (LDLr) deficiency (LDLr-/-) in mice. Replication-defective adenovirus containing the human LPL cDNA driven by a cytomegalovirus promoter (Ad.hLPL) efficiently transduced CHO-ldlA7 cells in vitro, inducing in these cells the production of bioactive LPL (73 mU/ml). Intravenous injection of Ad.hLPL (2 x 10(9) pfu) led to high-level expression of hLPL mRNA and LPL activity in the liver (88.3 mU/ml) and in post-heparin plasma (116.1 mU/ml). Overexpression of LPL resulted in marked reductions in total plasma cholesterol (TC; 48%, 43%, 25%) and triglycerides (TTg; 63%, 40%, 70%, p < 0.01) in apoE-/-, LDLr-/-, and wild-type (WT) mice, respectively. Fast protein liquid chromatography (FPLC) fractionation of plasma lipoproteins showed a marked decrease in very-low-density lipoprotein (VLDL)/chylomicron remnant cholesterol (V/CR-C) in apoE-/- (83%), LDLr-/- (84%), and WT mice (58%, p < 0.01). VLDL/chylomicron remnant triglycerides (V/CR-Tg) were virtually eliminated in apoE-/- (92%), LDLr-/- (86%), and WT mice (84%, p < 0.05). No significant changes were detected in LPL activities, plasma lipids, or lipoproteins of mice injected with a control virus, Ad.Luc, containing the luciferase instead of the LPL cDNA. In summary, infusion of Ad.hLPL leads to increased liver and post-heparin plasma LPL activities, significantly reduced TC, TTg, V/CR-C, and V/CR-Tg in WT mice, as well as in mice with apoE and LDLr deficiencies. Adenovirus-mediated LPL gene transfer to the liver is an effective means of reversing many of the lipoprotein abnormalities in apoE- and LDLr-deficient mice.
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PMID:Adenovirus-mediated gene transfer of human lipoprotein lipase ameliorates the hyperlipidemias associated with apolipoprotein E and LDL receptor deficiencies in mice. 938 58

To demonstrate potential therapeutic effects of kallikrein gene delivery in salt-induced hypertension and renal diseases, we delivered adenovirus carrying the human tissue kallikrein gene (Ad.CMV-cHK) into deoxycorticosterone acetate (DOCA)-salt hypertensive rats. A single intravenous injection of Ad.CMV-cHK caused a delay in the rise of blood pressure that began 2 days post gene delivery and lasted for more than 23 days. A maximal blood pressure reduction of 50 mm Hg was observed in rats receiving kallikrein gene delivery, as compared to rats receiving adenovirus containing the luciferase gene (Ad.CMV-Luc) (172 +/- 5 vs. 222 +/- 13 mm Hg, n = 6, P < 0.01). Throughout the experimental period, a blood pressure reduction of at least 32 mm Hg was observed in the DOCA-salt rats injected with Ad.CMV-cHK as compared to DOCA-salt rats receiving control adenovirus. Immunoreactive human tissue kallikrein levels were detected in rat serum and urine post gene delivery. Adenovirus-mediated kallikrein gene delivery caused a significant reduction in urinary excretion, urinary protein levels and body weight. Morphological examination of the kidney showed that kallikrein gene transfer significantly reduced DOCA-salt-induced glomerular sclerotic lesions, brush border disruption of proximal tubules, tubular dilatation and protein cast accumulation. These findings showed that the expression of human tissue kallikrein via gene delivery has protective effects against hypertension and renal injury in DOCA-salt hypertensive rats.
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PMID:Adenovirus-mediated kallikrein gene delivery attenuates hypertension and protects against renal injury in deoxycorticosterone-salt rats. 1060 25


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