bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevention of Virus Persistence and Protection against Immunopathology after Borna Disease Virus Infection of the Brain by a Novel Orf Virus Recombinant
Authors: Henkel Marco , Planz Oliver , Fischer Timo , Stitz Lothar , Rziha Hanns-Joachim 
Published: December 2004

ABSTRACTTheParapoxvirus Orf virusrepresents a promising candidate for novel vector vaccines due to its immune modulating properties even in nonpermissive hosts such as mouse or rat. The highly attenuated Orf virus strain D1701 was used to generate a recombinant virus (D1701-VrVp40) expressing nucleoprotein p40 of Borna disease virus, which represents a major antigen for the induction of a Borna disease virus-specific humoral and cellular immune response. Infection with Borna disease virus leads to distinct neurological symptoms mediated by the invasion of activated specific CD8+T cells into the infected brain. Usually, Borna disease virus is not cleared from the brain but rather persists in neural cells. In the present study we show for the first time that intramuscular application of the D1701-VrVp40 recombinant protected rats against Borna disease, and importantly, virus clearance from the infected brain was demonstrated in immunized animals. Even 4 and 8 months after the last immunization, all immunized animals were still protected against the disease. Initial characterization of the immune cells attracted to the infected brain areas suggested that D1701-VrVp40 mediated induction of B cells and antibody-producing plasma cells as well as T cells. These findings suggest the induction of various defense mechanisms against Borna disease virus. First studies on the role of antiviral cytokines indicated that D1701-VrVp40 immunization did not lead to an enhanced early response of gamma or alpha interferon or tumor necrosis factor alpha. Collectively, this study describes the potential of the Orf virus vector system in mediating long-lasting, protective antiviral immunity and eliminating this persistent virus infection without provoking massive neuronal damage.
Inverted Terminal Repeat Sequences Are Important for Intermolecular Recombination and Circularization of Adeno-Associated Virus Genomes
Authors: Yan Ziying , Zak Roman , Zhang Yulong , Engelhardt John F. 
Published: December 2004

ABSTRACT
The relatively small package capacity (less than 5 kb) of adeno-associated virus (AAV) vectors has been effectively doubled with the development of dual-vector heterodimerization approaches. However, the efficiency of such dual-vector systems is limited not only by the extent to which intermolecular recombination occurs between two independent vector genomes, but also by the directional bias required for successful transgene reconstitution following concatemerization. In the present study, we sought to evaluate the mechanisms by which inverted terminal repeat (ITR) sequences mediate intermolecular recombination of AAV genomes, with the goal of engineering more efficient vectors for dual-vector trans-splicing approaches. To this end, we generated a novel AAV hybrid-ITR vector characterized by an AAV-2 and an AAV-5 ITR at opposite ends of the viral genome. This hybrid genome was efficiently packaged into either AAV-2 or AAV-5 capsids to generate infectious virions. Hybrid AV2:5 ITR viruses had a significantly lower capacity to form circular intermediates in infected cells than homologous AV2:2 and AV5:5 ITR vectors despite their similar capacity to express an encoded enhanced green fluorescent protein (EGFP) transgene. To examine whether the divergent ITR sequences contained within hybrid AV2:5 ITR vectors could direct intermolecular recombination in a tail-to-head fashion, we generated two hybrid ITR trans-splicing vectors (AV5:2LacZdonor and AV2:5LacZacceptor). Each delivered one exon of a β-galactosidase minigene flanked by donor or acceptor splice sequences. These hybrid trans-splicing vectors were compared to homologous AV5:5 and AV2:2 trans-splicing vector sets for their ability to reconstitute β-galactosidase gene expression. Results from this comparison demonstrated that hybrid ITR dual-vector sets had a significantly enhanced trans-splicing efficiency (6- to 10-fold, depending on the capsid serotype) compared to homologous ITR vectors. Molecular studies of viral genome structures suggest that hybrid ITR vectors provide more efficient directional recombination due to an increased abundance of linear-form genomes. These studies provide direct evidence for the importance of ITR sequences in directing intermolecular and intramolecular homologous recombination of AAV genomes. The use of hybrid ITR AAV vector genomes provides new strategies to manipulate viral genome conversion products and to direct intermolecular recombination events required for efficient dual-AAV vector reconstitution of the transgene.
Dendritic Cells and Macrophages Are Productively Infected by Poliovirus
Authors: Wahid Rahnuma , Cannon Martin J. , Chow Marie 
Published: December 2004

ABSTRACTExpression of the poliovirus receptor (PVR) on cells is a major host determinant of infection by poliovirus. Previously, the only immune cell type known to express PVR was the blood-derived monocyte, which is susceptible to infection at very low frequency. We demonstrate that professional antigen-presenting cells—macrophages and dendritic cells, generated upon differentiation of monocytes—retain expression of PVR and are highly susceptible to infection by type 1 Mahoney strain of poliovirus. Maximal cell-associated titers of virus are obtained within 6 to 8 h postinfection, and cell death and lysis occurs within 24 h postinfection. Similar kinetics are observed in cells infected with the Sabin 1 vaccine strain. Although protein synthesis and receptor-mediated endocytosis are inhibited upon poliovirus infection of these critical antigen-presenting cells, we demonstrate for the first time that functional presentation of antigen occurs in these infected cells via the HLA class II pathway.
The Epstein-Barr Virus BILF1 Gene Encodes a G Protein-Coupled Receptor That Inhibits Phosphorylation of RNA-Dependent Protein Kinase
Authors: Beisser Patrick S. , Verzijl Dennis , Gruijthuijsen Yvonne K. , Beuken Erik , Smit Martine J. , Leurs Rob , Bruggeman Cathrien A. , Vink Cornelis 
Published: December 2004

ABSTRACT

Epstein-Barr virus (EBV) infection is associated with many lymphoproliferative diseases, such as infectious mononucleosis and Burkitt's lymphoma. Consequently, EBV is one of the most extensively studied herpesviruses. Surprisingly, a putative G protein-coupled receptor (GPCR) gene of EBV, BILF1, has hitherto escaped attention, yet BILF1-like genes are conserved among all known lymphocryptovirus species, suggesting that they play a pivotal role in viral infection. To determine the function of EBV BILF1, the activity of this gene and its products was studied. BILF1-specific mRNA was detected in various EBV-positive cell types and found to be expressed predominantly during the immediate early and early phases of infection in vitro. Interestingly, in COS-7 cells transfected with BILF1 expression constructs, a decrease in forskolin-induced CRE-mediated transcription was measured, as well as an increase in NF-κB-mediated transcription. In contrast, CRE-mediated transcription was increased in EBV-positive Burkitt's lymphoma cells as well as EBV-positive lymphoblastoid B cells transfected with BILF1, whereas NF-κB-mediated transcription levels remained unaffected in these cells. All observed activities were sensitive to treatment with pertussis toxin, indicating that the BILF1-encoded protein mediates these activities by coupling to G proteins of the G
i/o
class. Finally, reduced levels of phosphorylated RNA-dependent antiviral protein kinase were observed in COS-7 and Burkitt's lymphoma cells transfected with BILF1. Neither of the observed effects required a ligand to interact with the BILF1 gene product, suggesting that BILF1 encodes a constitutively active GPCR capable of modulating various intracellular signaling pathways.
R5 Human Immunodeficiency Virus Type 1 Infection of Fetal Thymic Organ Culture Induces Cytokine and CCR5 Expression
Authors: Choudhary Shailesh K. , Choudhary Neelima R. , Kimbrell Katherine C. , Colasanti Jonathan , Ziogas Argyrios , Kwa David , Schuitemaker Hanneke , Camerini David 
Published: December 2004

ABSTRACTLate-stage CCR5 tropic human immunodeficiency virus type 1 (HIV-1) isolates (R5 HIV-1) can deplete nearly all CD4+thymocytes from human thymus/liver grafts, despite the fact that fewer than 5% of these cells express CCR5. To resolve this paradox, we studied the replication and cytopathic effects (CPE) of late-stage R5 HIV-1 biological clones from two progressors and two long-term nonprogressors (LTNP) in fetal thymic organ culture (FTOC) with and without added cytokines. We found that R5 HIV-1 clones from progressors but not LTNP were cytopathic in untreated FTOC. Moreover, R5 HIV-1 clones from progressors replicated to higher levels than LTNP-derived R5 HIV-1 clones in this system. In contrast, when FTOC was maintained in the presence of interleukin 2 (IL-2), IL-4, and IL-7, both progressor and LTNP clones exhibited similar replication and CPE, which were equal to or greater than the levels achieved by progressor-derived R5 HIV-1 clones in untreated FTOC. This finding was likely due to IL-2-induced CCR5 expression on CD4+thymocytes in FTOC. R5 HIV-1 clones showed greater pathogenesis for CCR5+cells but also showed evidence of CPE on CCR5−cells. Furthermore, infection of FTOC by R5 HIV-1 induced IL-10 and transforming growth factor β (TGF-β) expression. Both IL-10 and TGF-β in turn induced CCR5 expression in FTOC. Induction of CCR5 expression via cytokine induction by R5 HIV-1 infection of CCR5+thymocytes likely permitted further viral replication in newly CCR5+thymocytes. CCR5 expression, therefore, is a key determinant of pathogenesis of R5 HIV-1 in FTOC.
Posttranscriptional Suppression of Interleukin-6 Production by Human Cytomegalovirus
Authors: Gealy Claire , Denson Marian , Humphreys Christine , McSharry Brian , Wilkinson Gavin , Caswell Richard 
Published: December 2004

ABSTRACTHuman cytomegalovirus (HCMV) has evolved multiple strategies for suppression of the antiviral response of the infected cell. DNA array technology has revealed that HCMV clearly regulates host gene expression during the course of a productive infection by enhancing, sustaining, or suppressing steady-state levels of cellular transcripts. Interleukin-6 (IL-6) is a pleiotropic cytokine that plays a central role in the immune response to infection. Here we report a detailed study of the effects of HCMV infection on IL-6 expression by human fibroblasts. UV-inactivated virus was found to induce high levels of IL-6 mRNA and protein expression, and IL-6 mRNA remained abundant in cells 16 h after inoculation even though the level of ongoing IL-6 transcription was not significantly enhanced. In lytic HCMV infections, the onset of viral gene expression resulted in two apparently antagonistic effects on IL-6 expression: (i) transcriptional activation, mediated at least in part by the IE2p86 protein, and (ii) posttranscriptional suppression mediated by destabilization of IL-6 mRNA. Transcriptional activation was outweighed by the suppressive effect, such that cells undergoing productive infection produced less IL-6 than cells challenged with inactivated virus. Suppression of IL-6 expression was independent of the viral IL-10 homologue, cmvIL-10. Destabilization of IL-6 mRNA was observed to coincide with the enhanced expression and aberrant intracellular localization of HuR, an mRNA-binding protein known to interact with IL-6 and other mRNAs containing 3′ AU-rich elements. Our data suggest a novel mechanism for gene regulation by HCMV at the posttranscriptional level.
Epstein-Barr Virus-Encoded BILF1 Is a Constitutively Active G Protein-Coupled Receptor
Authors: Paulsen Sarah J. , Rosenkilde Mette M. , Eugen-Olsen Jesper , Kledal Thomas N. 
Published: December 2004

ABSTRACT

Both beta- and gammaherpesviruses encode G protein-coupled receptors (GPCRs) with unique pharmacological phenotypes and important biological functions. An example is ORF74, the γ2-herpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded GPCR, which is highly constitutively active and considered the key oncogene in Kaposi's sarcoma pathogenesis. In contrast, the current annotation of the Epstein-Barr virus (EBV) genome does not reveal any GPCR homolog encoded by this human oncogenic γ1-herpesvirus. However, by employing bioinformatics, we recognized that the previously established EBV open reading frame
BILF1
indeed encodes a GPCR. Additionally, BILF1 is a member of a new family of related GPCRs exclusively encoded by γ1-herpesviruses. Expression of hemagglutinin-tagged BILF1 in the HEK293 epithelial cell line revealed that BILF1 is expressed as an approximately 50-kDa glycosylated protein. Immunocytochemistry and confocal microscopy revealed that BILF1 localizes predominantly to the plasma membrane, similar to the localization of KSHV ORF74. Using chimeric G proteins, we found that human and rhesus EBV-encoded BILF1 are highly potent constitutively active receptors, activating Gα
i
. Furthermore, BILF1 is able to inhibit forskolin-triggered CREB activation via stimulation of endogenous G proteins in a pertussis toxin-sensitive manner, verifying that BILF1 signals constitutively through Gα
i
. We suggest that EBV may use BILF1 to regulate Gα
i
-activated pathways during viral lytic replication, thereby affecting disease progression.
Evolutionary Trace Residues in Noroviruses: Importance in Receptor Binding, Antigenicity, Virion Assembly, and Strain Diversity
Authors: Chakravarty Sugoto , Hutson Anne M. , Estes Mary K. , Prasad B. V. Venkataram 
Published: December 2004

ABSTRACT
Noroviruses cause major epidemic gastroenteritis in humans. A large number of strains of these single-stranded RNA viruses have been reported. Due to the absence of infectious clones of noroviruses and the high sequence variability in their capsids, it has not been possible to identify functionally important residues in these capsids. Consequently, norovirus strain diversity is not understood on the basis of capsid functions, and the development of therapeutic compounds has been hampered. To determine functionally important residues in noroviruses, we have analyzed a number of norovirus capsid sequences in the context of the Norwalk virus capsid crystal structure by using the evolutionary trace method. This analysis has identified capsid protein residues that uniquely characterize different norovirus strains and provide new insights into capsid assembly and disassembly pathways and the strain diversity of these viruses. Such residues form specific three-dimensional clusters that may be of functional importance in noroviruses. One of these clusters includes residues known to participate in the proteolytic cleavage of these viruses at high pH. Other clusters are formed in capsid regions known to be important in the binding of antibodies to noroviruses, thereby indicating residues that may be important in the antigenicity of these viruses. The highly variable region of the capsid shows a distinct cluster whose residues may participate in norovirus-receptor interactions.
Effects of Febrile Temperature on Adenoviral Infection and Replication: Implications for Viral Therapy of Cancer
Authors: Thorne Stephen H. , Brooks Gabriel , Lee Yeun-Ling , Au Tina , Eng Lawrence F. , Reid Tony 
Published: December 2004

ABSTRACT

We previously conducted a phase I/II study using arterial infusions of ONYX-015 (
dl
1520), a replication-selective adenoviral vector, with E1b deleted, for patients with metastatic colorectal cancer. No dose-limiting toxicities occurred, but >90% of the patients experienced fever. The effects of temperature on the replication of
dl
1520 in normal and transformed cells had not been studied. Therefore, replication and cell viability assays were performed with a panel of nontransformed and transformed cell lines cultured at 37 and 39.5°C and treated with adenovirus type 5 (Ad5) or
dl
1520. Ad5-mediated cytolytic effects were inhibited and production of infectious particles decreased by >1,000-fold in the nontransformed cells at 39.5°C. Seven of nine of the tumor cell lines retained significant cell-killing effects when treated with Ad5 at 39.5°C. When
dl
1520 was used, no cytolytic effects were observed at 39.5°C in the nontransformed cell lines; however, cytolytic effects occurred in six of nine tumor cell lines at 39.5°C. Notably, a subset of the tumor cell lines demonstrated increased
dl
1520-mediated cytolytic effect and replication at 39.5°C. Suppression of Ad5 and
dl
1520 replication at 39.5°C was not related to p53 status or HSP70 expression. Also, at 39.5°C, E1a expression was inhibited in nontransformed cells but was still abundant in the transformed cells, indicating that a novel early block in viral replication occurred in the nontransformed cells. Fever may therefore augment the therapeutic index of oncolytic viruses by inhibiting replication in normal cells while permitting or enhancing viral replication in some tumor cells.
Adenovirus Early Region 3 Transgenes Expressed in β Cells Prevent Autoimmune Diabetes in Nonobese Diabetic Mice: Effects of Deleting the Adenovirus Death Protein 11.6K
Authors: Pierce Melissa A. , Svetlanov Anton , Horwitz Marshall S. , Serreze David V. 
Published: December 2004

ABSTRACT
The incidence of type 1 diabetes (T1D) is decreased in nonobese diabetic mice expressing the complete cassette of adenovirus early region 3 (E3) immunomodulating genes in pancreatic β cells. Embedded among the antiapoptotic E3 genes is one encoding an adenovirus death protein (ADP), which contributes to release of virion particles by promoting cell lysis. Because removal of this proapoptotic protein might have further enhanced the ability of E3 proteins to prevent T1D, an ADP-inactivated E3 construct was tested. Significantly, deletion of ADP did not improve the diabetes-protective effect of an E3 gene cassette.
Human Immunodeficiency Virus Type 1 Nef Domains Required for Disruption of Major Histocompatibility Complex Class I Trafficking Are Also Necessary for Coprecipitation of Nef with HLA-A2
Authors: Williams Maya , Roeth Jeremiah F. , Kasper Matthew R. , Filzen Tracey M. , Collins Kathleen L. 
Published: December 2004

ABSTRACT
Human immunodeficiency virus type 1 (HIV-1) Nef is a critical protein that is necessary for HIV pathogenesis. Its roles include the disruption of major histocompatibility complex class I (MHC-I) and CD4 trafficking to promote immune evasion and viral spread. Mutational analyses have revealed that separate domains of Nef are required to affect these two molecules. To further elucidate how Nef disrupts MHC-I trafficking in T cells, we examined the role of protein domains that are required for this function (N-terminal alpha helix, polyproline, acidic, and oligomerization domains). We found that each of these regions was required for Nef to disrupt the transport of HLA-A2 to the cell surface and for Nef to coprecipitate with HLA-A2.
Sindbis Virus with a Tricomponent Genome
Authors: Fayzulin Rafik , Gorchakov Rodion , Petrakova Olga , Volkova Evgenia , Frolov Ilya 
Published: December 2004

ABSTRACT
We established a system for propagation of Sindbis virus (SIN)-based replicons in tissue culture in the form of a tricomponent genome virus. Three RNA fragments containing complementing genetic information required for virus replication are packaged into separate viral particles, and each cell produces at least 1,000 packaged replicons and the number of packaged helpers sufficient to perform the next passage. This system can be used to generate large stocks of packaged replicons. The formation of infectious recombinant SIN virus was not detected in any experiments. These features make multicomponent genome SIN an attractive system for a variety of research and biotechnology applications.
Get rid of those election blues
Authors: Robinson Nick 
Published: December 2004

Journalists who could barely contain their excitement about the US elections now look ahead with almost universal gloom to the long British campaign ahead, writes the political editor of ITV News. While set and graphic designers gurgle with delight at their quadrennial licensed excess - election night sets that put the Pompidou Centre to shame, magical graphics that can fly you down the chimney of Number Ten right into Tony Blair's bedroom - reporters and producers are carping into their cappuccinos: "It's going to be so dull...I don't think I can bear it." Well, move aside for someone who understands that there is something special - magical even - about the moment the country makes its choice of who should lead it and, just as important, we all choose who should represent us where we live. Robinson presents his propositions designed to allay those pre-election blues.
Temozolomide for malignant gliomas in British Columbia: A population-based cost-effectiveness analysis
Authors: Greanya ED , Taylor SCM , BscPharm F Hu , Barnett J , Thiessen B 
Published: December 2004

Study objectives. To evaluate the cost-effectiveness and outcomes achieved in patients with recurrent malignant glioma treated with temozolomide in British Columbia, as compared to previous lomustine use in the same patient population, and to temozolomide literature reports. Outcomes assessed included median overall survival, 6-month overall survival and 6-month progression free survival. Methods. A retrospective analysis was conducted to identify patients who received single-agent temozolomide or lomustine during successive, prespecified time periods. Data was collected on survival, disease progression, duration of therapy, cost of drug, labour and supplies, and successive or prior chemotherapy. Results. Six-month progression free survival (PFS) occurred in 52% and 42.9% of patients in the temozolomide and lomustine cohorts, respectively (P=0.44). Six-month overall survival and median overall survival (OS) were 72% and 40.86 weeks for temozolomide patients and 64.3% and 46.7 weeks for lomustine patients. These outcomes were not statistically different between the two treatment groups. Associated with these outcomes, temozolomide patients received a median of six cycles of drug treatment, with a median cost per patient of $11 660 (CAN). Alternatively, lomustine patients received a median of four cycles with a median cost per patient of $189 (CAN). In the cost-effectiveness analysis for median OS, temozolomide was not a cost-effective alternative, and for 6-month PFS, the incremental cost effectiveness ratio (ICER) of temozolomide was $1261 (CAN) for each additional percent of patients progression free at 6-months. Sensitivity analysis varying both median OS and 6-month PFS resulted in ICER’s of temozolomide ranging from $332 to $3277. Conclusions. No significant differences in outcomes were observed between patients treated with single-agent lomustine or temozolomide. Temozolomide therapy has an incremental cost increase over lomustine of $11 471 per patient. It appears when only survival outcomes and direct treatment costs are considered, lomustine is a more cost-effective treatment strategy in the specific setting of recurrent malignant glioma.
Religion and urban regeneration: a place for faith?
Authors: Furbey Robert , Macey Marie 
Published: December 2004

English
The British government has identified ‘faith communities’ as a neglected resource in urban regeneration. This article first explores the context of official support for faith involvement in urban and neighbourhood policy and identifies the assumptions underlying key policy documents. These assumptions are then critically explored by reference to the links commonly drawn between religion and ‘community’, ‘neighbourhood’ and ‘social cohesion’. Attempts to enlist faith groups within this essentially consensual agenda often fail to recognise both the potential divisiveness of religion and also the more positive and radical lessons that often stem from the action, experience and critical analysis of religious organisations and their members.