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 differentiation and maturation of skeletal muscle cells into functional fibers is coordinated largely by inductive signals which act through discrete intracellular signal transduction pathways. Recently, the calcium-activated phosphatase calcineurin (PP2B) and the family of transcription factors known as NFAT have been implicated in the regulation of myocyte hypertrophy and fiber type specificity. Here we present an analysis of the intracellular mechanisms which underlie myocyte differentiation and fiber type specificity due to an insulinlike growth factor 1 (IGF-1)-calcineurin-NFAT signal transduction pathway. We demonstrate that calcineurin enzymatic activity is transiently increased during the initiation of myogenic differentiation in cultured C2C12 cells and that this increase is associated with NFATc3 nuclear translocation. Adenovirus-mediated gene transfer of an activated calcineurin protein (AdCnA) potentiates C2C12 and Sol8 myocyte differentiation, while adenovirus-mediated gene transfer of noncompetitive calcineurin-inhibitory peptides (cain or DeltaAKAP79) attenuates differentiation. AdCnA infection was also sufficient to rescue myocyte differentiation in an IGF-depleted myoblast cell line. Using 10T1/2 cells, we demonstrate that MyoD-directed myogenesis is dramatically enhanced by either calcineurin or NFATc3 cotransfection, while a calcineurin inhibitory peptide (cain) blocks differentiation. Enhanced myogenic differentiation directed by calcineurin, but not NFATc3, preferentially specifies slow myosin heavy-chain expression, while enhanced differentiation through mitogen-activated protein kinase kinase 6 (MKK6) promotes fast myosin heavy-chain expression. These data indicate that a signaling pathway involving IGF-calcineurin-NFATc3 enhances myogenic differentiation whereas calcineurin acts through other factors to promote the slow fiber type program.
Mol Cell Biol 2000 Sep
PMID:A calcineurin-NFATc3-dependent pathway regulates skeletal muscle differentiation and slow myosin heavy-chain expression. 1093 34

Several laboratories have attempted with little success to induce Fas-mediated apoptosis in prostate cancer (PCa) cells, using different external Fas agonists, i.e., anti-Fas antibodies and membrane-bound FasL. The present study confirms these earlier results using the anti-Fas antibody CH-11 in five human PCa cell lines (PPC-1, LNCaP, PC-3, TSU-Pr1, and DU145). However, intracellular murine FasL expression induced Fas-mediated apoptosis in all CH-11-resistant cell lines. Adenovirus (AdGFPFasL(TET)) was used to deliver a Murine FasL-GFP fusion gene into human PCa cells resulting in 70-98% apoptosis at 48 h as determined by the MTS assay. DU145 and PPC-1 cells treated with AdGFPFasL(TET) stained positive for the TUNEL assay, indicating that cell death was via apoptosis. Using immunofluorescent microscopy, Fas and GFPFasL colocalized to the same intracellular compartment. The anti-Fas neutralizing antibody ZB-4 was unable to block AdGFPFasL(TET)-mediated cell death, suggesting that intracellular FasL may ligate Fas within the Golgi and/or endoplasmic reticulum. This is the first evidence suggesting that these two molecules interact prior to cell surface presentation. Collectively, these findings indicate that intracellular GFPFasL expression is superior to CH-11 at inducing Fas-mediated apoptosis in human PCa cells and may allow use of AdGFPFasL(TET) for PCa gene therapy.
Mol Ther 2000 Oct
PMID:Intracellular Fas ligand expression causes Fas-mediated apoptosis in human prostate cancer cells resistant to monoclonal antibody-induced apoptosis. 1102 Mar 50

Adenovirus-mediated gene delivery is limited by the induction of immune responses that produce toxicity and prevent reexpression. To determine whether adenoviral delivery in the preimmune fetus would produce tolerance, we assessed luciferase (luc) expression following sequential pre- and postnatal adenoviral-mediated gene delivery. Day 15 fetuses were injected intrahepatically with 1 x 10(7) pfu of an adenoviral-luc vector (Ad-luc). Following in utero injection, hepatic luc expression persisted 1 month postnatally. No humoral response to adenovirus or luc was detected. Adult mice, previously injected in utero, were reinjected intravenously with 5 x 10(8) pfu of Ad-luc at 3 months of age and again at 6 months with either 5 x 10(8) pfu of Ad-luc or cationic liposome-DNA complexes (CLDC). Following the first postnatal injection, animals injected in utero had levels of luc comparable to those of age-matched naive controls. However, both control and experimental animals subsequently developed antibodies to adenovirus and luc. No further expression was achieved with a second postnatal injection of Ad-luc or with delivery of CLDC-luc. These studies demonstrate that the delivery of adenoviral vectors in utero at E15 does not elicit an immune response. However, delivery of recombinant adenovirus postnatally results in brisk and limiting immune responses regardless of the in utero exposure.
Mol Ther 2000 Oct
PMID:Reexpression following readministration of an adenoviral vector in adult mice after initial in utero adenoviral administration. 1102 Mar 44

Host inflammatory and immune responses limit viral gene expression after administration of replication-deficient adenoviruses to the lung. The current study asks whether inducible nitric oxide synthase (iNOS) expression and peroxynitrite generation accompanied the inflammatory response following intratracheal administration of adenovirus. Pulmonary iNOS mRNA and protein were increased 2, 7, and 14 days following administration of 2 x 10(9) plaque-forming units of recombinant adenovirus (Av1Luc1) to BALB/c mice. Adenovirus infection was associated with a marked increase in nitrotyrosine staining. Intense nitrotyrosine staining was observed in alveolar macrophages, respiratory epithelial cells, conducting airways, and alveolar spaces 2 days postinfection. Two weeks after exposure to adenovirus, nitrotyrosine staining was detected within alveolar macrophages, suggesting adenovirus enhanced the nitration of proteins that were subsequently taken up by alveolar macrophages. Western blot analysis using anti-nitrotyrosine antibody did not demonstrate accumulation of nitrated surfactant protein A (SP-A), although a small fraction of aggregated SP-A comigrated with a nitrotyrosine-positive protein. iNOS expression, peroxynitrite, and nitrotyrosine generation accompany and may contribute to inflammatory responses to adenovirus in the lung.
Am J Physiol Lung Cell Mol Physiol 2001 Mar
PMID:Adenovirus infection increases iNOS and peroxynitrite production in the lung. 1115 34

Adenovirus (Ad)-mediated gene transfer to the respiratory epithelium of experimental animals and to nasal and airway epithelium of individuals with cystic fibrosis is followed by transient gene expression. Extensive studies in experimental animals are consistent with the concept that local cellular host anti-vector immune responses account for this short-term expression, and systemic and local [lung epithelial lining fluid (ELF)] anti-Ad neutralizing antibodies are generated following Ad vector administration to the respiratory epithelial surface. To determine if this paradigm holds in normal humans, a first-generation Ad vector (Ad(GV)CD.10, an E1(-)E3(-) Ad serotype 5-based vector coding for the Escherichia coli cytosine deaminase gene) was sprayed locally in escalating doses (8 x 10(8)-8 x 10(10) particle units (pu), n = 2/group) into the lung airway epithelium of six normal individuals. Serum, ELF, and endobronchial biopsies were obtained at baseline and at various time points following vector administration. In contrast to the observations in experimental animals in which lung administration of first-generation Ad vectors is followed by strong systemic and local host response, bronchial spray administration of the Ad vector to normal humans showed: (1) minimal inflammation in bronchial biopsies, bronchial brushing, and bronchoalveolar lavage fluid; (2) no blood lymphocyte proliferation in five of six individuals in response to in vitro stimulation with Ad antigens; and (3) no significant increase from baseline in blood or lung ELF anti-Ad neutralizing antibodies. Despite this minimal normal human anti-Ad host response, dose-dependent levels of vector DNA in the airway epithelium were transient. Vector DNA in the targeted airway epithelial cells peaked in a dose-dependent fashion at 0.007 to 1.1 copies/cell at day 7 and declined thereafter, reducing to <10% of peak levels by 2 weeks. These observations demonstrate both the strengths and the limits of using experimental animals to predict human responses to gene transfer vectors. While the transient nature of Ad vector persistence in the airway epithelium is predicted by most experimental animal studies, respiratory epithelial administration of first-generation Ad vectors at doses up to 10(10) pu to airway epithelium of healthy individuals elicits minimal to no detectable systemic and mucosal humoral and cellular immune responses, an observation diametrically opposed to the host responses measured in experimental animals. These findings suggest that, while adaptive anti-Ad immune responses likely play some role in the disappearance of the vector DNA following vector administration to the human lung, other mechanisms may also be involved in the response of humans to Ad gene transfer vectors.
Mol Ther 2001 Feb
PMID:Host responses and persistence of vector genome following intrabronchial administration of an E1(-)E3(-) adenovirus gene transfer vector to normal individuals. 1123 77

Advances in understanding the interaction of animal viruses with their cognate receptors has led to improvements in the development of cell-specific, targeted viral vectors. Research strategies to generate safe, non-inflammatory viral vectors that are capable of delivering a therapeutic gene to a specific population of cells are currently underway in many laboratories. One approach in the utilization of this cell targeting activity is to ablate the natural interaction of the virus with its native receptor, although this is not an absolute requirement. The initial development of 'viral targeting strategies' was based on the view that by modifying the viral protein/receptor interaction, it would be possible to redirect virus vectors to new host cells. As the understanding of virus/cell interactions increased it was observed, however, that many viruses can use different entry mechanisms for cell attachment and penetration. Adenovirus vectors have been used extensively for the delivery of genes to cells. The entry mechanism for adenoviruses into cells has recently been studied and is relatively well understood, however, there are many aspects of cell receptor/virus interactions, which have still to be elucidated. The single high-affinity receptor on mammalian cells for adenovirus type 5 is recognized as the coxsackie and adenovirus receptor. However, in the absence of coxsackie and adenovirus receptor other receptors are used. A thorough understanding of the biology of adenoviruses is essential in the further development of their use as vectors for cell targeting. One strategy is to modify the viral capsid, either through coating the surface using bispecific antibodies, or by chemically crosslinking the targeting ligand onto the virion surface. Another approach is to genetically modify the virus by incorporating the targeting ligand into the viral 'spike' (fiber) protein. This involves manipulating the adenovirus genome and generating a new targeting ligand on the surface of the fiber protein using recombinant DNA technology. The penton base protein has also received attention as a means of directing adenoviruses via insertion of novel targeting ligands.
Curr Opin Mol Ther 2000 Oct
PMID:Biophysical targeting of adenovirus vectors for gene therapy. 1124 55

The tumor suppressor p53 is known to regulate gene transcription and apoptosis in mammalian cells. In the present study we ascertain whether these events are mutually dependent and obligatorily linked for induction of apoptosis of ventricular myocytes. Adenovirus mediated gene delivery of wild p53 (p53WT) or a mutant form of p53 (p53MT) defective for gene transcription to ventricular myocytes was confirmed by Western blot analysis. A significant increase in the p53 dependent genes Bax and MDM2 was observed with p53WT but not p53MT. Nuclear DNA visualized by agarose gel electrophoresis revealed nucleosomal DNA laddering in the presence of either p53 protein. Apoptosis was substantiated by Hoechst 33258 nuclear staining. Perturbations to mitochondria consistent with the mitochondrial death pathway, including loss of mitochondrial transmembrane potential Delta(psi)m and cytochrome c release were observed with p53WT and p53MT. An increase in caspase 3-like activity was noted with either p53WT or p53MT protein that was suppressed by the caspase 3 inhibitor Ac-DEVD-CHO. To our knowledge the experiments described here provide the first indication that p53 activates the mitochondrial death pathway and provokes apoptosis of ventricular myocytes independent of DNA binding and de novo gene activation.
J Mol Cell Cardiol 2001 Aug
PMID:p53 activates the mitochondrial death pathway and apoptosis of ventricular myocytes independent of de novo gene transcription. 1144 32

Cardiac hypertrophy is one of the serious complications which increase mortality due to cardiovascular diseases. However, only a partial reduction of cardiac hypertrophy has been successful using current drug therapy. We demonstrate here reduction of cardiac hypertrophy in vitro and in vivo using an adenovirus vector encoding cyclin-dependent kinase (cdk) inhibitor p16INK4a. Adenovirus-mediated overexpression of cdk inhibitor p16INK4a completely inhibited cardiac myocyte hypertrophy induced by endothelin (ET)-1, as evaluated by [3H]leucine incorporation into the cells and mRNA levels of skeletal alpha -actin (SK-A) or atrial natriuretic peptide (ANP) as well as by morphometric analyses. We then evaluated whether p16INK4a can suppress left-ventricular (LV) hypertrophy induced by aortic banding (AOB) in rats. Catheter-mediated gene transfer of AxCAp16 was performed according to the method reported by Hajjar et al. LV overload was produced by coarctation of the ascending aorta immediately after inoculation of the heart with adenovirus. Two weeks after the procedure, the left ventricular weight/body weight ratio (LVW/BW) increased in the AOB+LacZ group in comparison to that in controls. However, LVW/BW was identical in the AOB+p16 group and controls. Histologic analysis revealed that p16INK4a inhibited hypertrophy of cardiac myocytes. These results suggest that G1 cell cycle regulators may restrict cardiac hypertrophy, and offer a novel strategy for the gene therapy of cardiac hypertrophy.
J Mol Cell Cardiol 2001 Aug
PMID:Overexpression of cdk Inhibitor p16INK4a by adenovirus vector inhibits cardiac hypertrophy in vitro and in vivo: a novel strategy for the gene therapy of cardiac hypertrophy. 1160 19

In pancreatic beta-cells, voltage-dependent K(+) (Kv) channels are potential mediators of repolarization, closure of Ca(2+) channels, and limitation of insulin secretion. The specific Kv channels expressed in beta-cells and their contribution to the delayed rectifier current and regulation of insulin secretion in these cells are unclear. High-level protein expression and mRNA transcripts for Kv1.4, 1.6, and 2.1 were detected in rat islets and insulinoma cells. Inhibition of these channels with tetraethylammonium decreased I(DR) by approximately 85% and enhanced glucose-stimulated insulin secretion by 2- to 4-fold. Adenovirus-mediated expression of a C-terminal truncated Kv2.1 subunit, specifically eliminating Kv2 family currents, reduced delayed rectifier currents in these cells by 60-70% and enhanced glucose-stimulated insulin secretion from rat islets by 60%. Expression of a C-terminal truncated Kv1.4 subunit, abolishing Kv1 channel family currents, reduced delayed rectifier currents by approximately 25% and enhanced glucose-stimulated insulin secretion from rat islets by 40%. This study establishes that Kv2 and 1 channel homologs mediate the majority of repolarizing delayed rectifier current in rat beta-cells and that antagonism of Kv2.1 may prove to be a novel glucose-dependent therapeutic treatment for type 2 diabetes.
Mol Endocrinol 2001 Aug
PMID:Members of the Kv1 and Kv2 voltage-dependent K(+) channel families regulate insulin secretion. 1146 64

Adenovirus (Adv)-mediated gene transfer requires efficient infection of target cells. The objective of this study was to establish whether alveolar macrophages (AM) and T cells (AT) from sarcoid patients were permissive to infection with Adv vectors and if this property could be used to investigate cytokine gene regulation. Sarcoid and normal bronchoalveolar lavage (BAL) specimens infected with Adv vectors expressing either beta-galactosidase or a green fluorescent protein were analyzed for transgene expression by fluorescence-activated cell sorter (FACS) and direct immunofluorescence, respectively. Expression of surface antigens previously associated with Adv infection, the coxsackie/adenovirus receptor (CAR), alpha v beta 3, and alpha v beta 5 integrins, was also assessed using FACS analysis. Sarcoid AM and AT were found to efficiently express Adv transgenes, unlike AM from normal volunteers, peripheral blood monocytes, and peripheral blood T cells. Cells permissive to Adv infection expressed the CAR and alpha v beta 5 integrin (also alpha v beta 3 integrin for AM). The data indicate that the upregulation of Adv receptors and the ability to infect sarcoid AM and AT are related to the inflammatory environment within the lung. Having demonstrated efficient Adv-mediated transgene delivery to sarcoid AM and AT, a construct encoding porcine I kappa B alpha was then used to investigate the requirement for nuclear factor (NF)-kappa B in the regulation of cytokine gene expression in pulmonary sarcoidosis. Overexpression of I kappa B alpha in sarcoid BAL specimens indicated that tumor necrosis factor-alpha and interleukin (IL)-6 production by AM and interferon (IFN)-gamma production by AT is NF-kappa B dependent, whereas IL-4 production by AT is NF-kappa B independent. This is the first occasion that the requirement for NF-kappa B in IFN-gamma gene expression within primary human T cells has been demonstrated. The results of this study have implications for the future investigation of molecular pathways in inflammatory lung disease.
Am J Respir Cell Mol Biol 2001 Aug
PMID:Alveolar macrophages and T cells from sarcoid, but not normal lung, are permissive to adenovirus infection and allow analysis of NF-kappa b-dependent signaling pathways. 1150 22


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