bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oncolytic vaccinia virus armed with the endostatin‐angiostatin fusion protein; a novel therapy for head and neck cancer
Authors: Tysome J. , Alusi G. , Fodor I. , Lemoine N. , Wang Y. 
Published: June 2008

Objectives.  The survival of patients with head and neck squamous cell carcinoma (HNSCC) has not improved significantly over recent decades. This had lead to the development of new therapies. Oncolytic viral therapy is a promising new strategy for cancer treatment. The first oncolytic virus licensed for treatment was an adenovirus for HNSCC.1 However, the outcomes of clinical trials using viral monotherapy have been disappointing. Oncolytic vaccinia virus represents an attractive alternative as its replication is less dependent than adenovirus on the genetic make‐up of host cells and it has been used safely as the smallpox vaccine in millions of patients.2Method.  This study evaluated the potential of vaccinia virus as a treatment for HNSCC in vitro and in human xenograft models in vivo.Results.  The Lister strain of vaccinia virus was more potent than adenovirus against all tumour cells tested in vitro. The virus displayed high selectivity for cancer cells, sparing normal cells both in vitro and in vivo. In order increase antitumour potency, a novel vaccinia virus expressing the endostatin–angiostatin fusion protein was constructed. This inhibits new blood vessel formation as well as tumour growth by oncolysis. The protein was both expressed in virus‐infected tumour cells and demonstrated function by the inhibition of human umbilical vein epithelial cell proliferation and tube formation in vitro.Conclusions.  This novel vaccinia virus is a promising therapeutic agent for HNSCC, which requires further evaluation in vivo.References.  1 Garber K. (2006) China approves world's first oncolytic virus therapy for cancer treatment. J. Natl. Cancer Inst. 98, 298–3002 Thorne S.H., Bartlett D.L. & Kirn D.H. (2005) The use of oncolytic vaccinia viruses in the treatment of cancer: a new role for an old ally? Curr. Gene Ther. 5, 429–443
Therapeutic Efficacy of a Conjugate Vaccine Containing a Peptide Mimotope of Cryptococcal Capsular Polysaccharide Glucuronoxylomannan
Authors: Datta Kausik , Lees Andrew , Pirofski Liise-anne 
Published: June 2008

ABSTRACTVaccination with P13, a peptide mimotope of the cryptococcal capsular polysaccharide glucuronoxylomannan (GXM), has been shown to confer protection against a subsequent lethalCryptococcus neoformanschallenge. In this study, we sought to investigate whether P13-based vaccines could be effective in an already-established infection. To address this question, we developed a systemic chronic cryptococcal infection model. We vaccinated chronically infected mice with P13-protein conjugates and monitored their survival. Compared to the controls, the conjugates prolonged the survival of chronically infected mice. The degree of protection was a function of the mouse strain (BALB/c or C57BL/6), the carrier protein (tetanus toxoid or diphtheria toxoid), and the route of infection (intraperitoneal or intravenous). Serum GXM levels were correlated with the day of death, but the correlation was driven by the carrier protein and mouse strain. The passive transfer of heat-treated sera from P13 conjugate-vaccinated mice conferred protection to naïve BALB/c mice, indicating that antibody immunity could contribute to protection. The measurement of peripheral blood cytokine (gamma interferon [IFN-γ], interleukin-10 [IL-10], and IL-6) gene expression showed that P13 conjugate-vaccinated BALB/c and C57BL/6 mice mounted a strong Th2 (IL-10)-like response relative to the Th1 (IFN-γ)-like response, with the degree depending on the mouse strain and carrier protein. Taken together, our data suggest that a vaccine could hold promise in the setting of chronic cryptococcosis, and that vaccine efficacy could depend on immunomodulation and augmentation of the natural immune response of the host.
Detection of All Known Parechoviruses by Real-Time PCR
Authors: Nix W. Allan , Maher Kaija , Johansson E. Susanne , Niklasson Bo , Lindberg A. Michael , Pallansch Mark A. , Oberste M. Steven 
Published: June 2008

ABSTRACTTheParechovirusgenus of thePicornaviridaefamily contains two species,Human parechovirus(HPeV) andLjungan virus(LV). The HPeVs (including the former echoviruses 22 and 23, now HPeV type 1 (HPeV1) and HPeV2, respectively) cause a wide spectrum of disease, including aseptic meningitis, gastroenteritis, encephalitis, acute respiratory illness, and neonatal sepsis-like disease. The LVs were isolated from bank voles in Sweden during a search for an infectious agent linked to fatal myocarditis cases in humans. Because of the decline in use of cell culture and neutralization to investigate enterovirus-like disease, very few laboratories currently have the capability to test for parechoviruses. We have developed a real-time reverse transcription-PCR (RT-PCR) assay for detection of all known members of the genusParechovirus. The assay targets the conserved regions in the 5′ nontranslated region (5′NTR) of the parechovirus genome and can detect both HPeVs and LVs, unlike other published parechovirus 5′ NTR assays, which only detect known HPeVs or only LVs. HPeV and LV can be differentiated by sequencing the 5′NTR real-time RT-PCR amplicon, when needed. The assay is approximately 100 times more sensitive than cell culture and may be used to test original clinical specimens. The availability of a broad-specificity PCR method should facilitate the detection of new human parechoviruses, as well as new parechoviruses in other mammalian species, and provide an opportunity to investigate the role of these viruses in human and animal disease.
Sensitive Detection of Multiple Rotavirus Genotypes with a Single Reverse Transcription-Real-Time Quantitative PCR Assay
Authors: Gutiérrez-Aguirre Ion , Steyer Andrej , Boben Jana , Gruden Kristina , Poljšak-Prijatelj Mateja , Ravnikar Maja 
Published: June 2008

ABSTRACT
Rotaviruses are one of the major causes of diarrhea in infants and children under 5 years old, especially affecting developing countries. In natural disasters, fecal matter and potable waters can mix, allowing low, yet infective, concentrations of rotavirus to be present in water supplies, constituting a risk for the population. Any of the most commonly detected rotavirus genotypes could originate an outbreak. The development of a fast and sensitive method that could detect the broadest possible range of rotavirus genotypes would help with efficient diagnosis and prevention. We have designed a reverse transcription (RT)-real-time quantitative PCR approach targeted to the rotaviral VP2 gene, based on a multiple-sequence alignment of different human rotaviral strains. To overcome the high nucleotide sequence diversity, multiple forward and reverse primers were used, in addition to a degenerate probe. The performance of the assay was tested on isolates representing the most prevalent human genotypes: G1P[8], G2P[4], G3P[8], G4P[8], G9P[8], and G12P[8]. The developed method improved classical rotavirus detection by enzyme-linked immunosorbent assay and nested RT-PCR by 5 and at least 1 order of magnitude, respectively. A survey of 159 stool samples indicated that the method can efficiently detect a broad range of rotavirus strains, including different G-P genotype combinations of human, porcine, and bovine origin. No cross-reactivity was observed with other enteric viruses, such as astrovirus, sapovirus, and norovirus.
Dendritic Cells Preferentially Transfer CXCR4-Using Human Immunodeficiency Virus Type 1 Variants to CD4+T Lymphocytes intrans
Authors: van Montfort Thijs , Thomas Adri A. M. , Pollakis Georgios , Paxton William A. 
Published: June 2008

ABSTRACTHuman immunodeficiency virus type 1 (HIV-1) preferentially utilizes the CCR5 coreceptor for target cell entry in the acute phase of infection, while later in disease progression the virus switches to the CXCR4 coreceptor in approximately 50% of patients. In response to HIV-1 the adaptive immune response is triggered, and antibody (Ab) production is elicited to block HIV-1 entry. We recently determined that dendritic cells (DCs) can efficiently capture Ab-neutralized HIV-1, restore infectivity, and transmit infectious virus to target cells. Here, we tested the effect of Abs ontranstransmission of CCR5 or CXCR4 HIV-1 variants. We observed that transmission of HIV-1 by immature as well as mature DCs was significantly higher for CXCR4- than CCR5-tropic viral strains. Additionally, neutralizing Abs directed against either the gp41 or gp120 region of the envelope such as 2F5, 4E10, and V3-directed Abs inhibited transmission of CCR5-tropic HIV-1, whereas Ab-treated CXCR4-tropic virus demonstrated unaltered or increased transmission. To further study the effects of coreceptor usage we tested molecularly cloned HIV-1 variants with modifications in the envelope that were based on longitudinal gp120 V1 and V3 variable loop sequences from a patient progressing to AIDS. We observed that DCs preferentially facilitated infection of CD4+T lymphocytes of viral strains with an envelope phenotype found late in disease. Taken together, our results illustrate that DCs transmit CXCR4-tropic HIV-1 much more efficiently than CCR5 strains; we hypothesize that this discrimination could contribute to the in vivo coreceptor switch after seroconversion and could be responsible for the increase in viral load.
Human Immunodeficiency Virus Infection Alters Tumor Necrosis Factor Alpha Production via Toll-Like Receptor-Dependent Pathways in Alveolar Macrophages and U1 Cells
Authors: Nicol Marlynne Q. , Mathys Jean-Marie , Pereira Albertina , Ollington Kevin , Ieong Michael H. , Skolnik Paul R. 
Published: June 2008

ABSTRACTHuman immunodeficiency virus (HIV)-positive persons are predisposed to pulmonary infections, even after receiving effective highly active antiretroviral therapy. The reasons for this are unclear but may involve changes in innate immune function. HIV type 1 infection of macrophages impairs effector functions, including cytokine production. We observed decreased constitutive tumor necrosis factor alpha (TNF-α) concentrations and increased soluble tumor necrosis factor receptor type II (sTNFRII) in bronchoalveolar lavage fluid samples from HIV-positive subjects compared to healthy controls. Moreover, net proinflammatory TNF-α activity, as measured by the TNF-α/sTNFRII ratio, decreased as HIV-related disease progressed, as manifested by decreasing CD4 cell count and increasing HIV RNA (viral load). Since TNF-α is an important component of the innate immune system and is produced upon activation of Toll-like receptor (TLR) pathways, we hypothesized that the mechanism associated with deficient TNF-α production in the lung involved altered TLR expression or a deficit in the TLR signaling cascade. We found decreased Toll-like receptor 1 (TLR1) and TLR4 surface expression in HIV-infected U1 monocytic cells compared to the uninfected parental U937 cell line and decreased TLR message in alveolar macrophages (AMs) from HIV-positive subjects. In addition, stimulation with TLR1/2 ligand (Pam3Cys) or TLR4 ligand (lipopolysaccharide) resulted in decreased intracellular phosphorylated extracellular signal-regulated kinase and subsequent decreased transcription and expression of TNF-α in U1 cells compared to U937 cells. AMs from HIV-positive subjects also showed decreased TNF-α production in response to these TLR2 and TLR4 ligands. We postulate that HIV infection alters expression of TLRs with subsequent changes in mitogen-activated protein kinase signaling and cytokine production that ultimately leads to deficiencies of innate immune responses that predispose HIV-positive subjects to infection.
Zinc Finger Proteins Designed To Specifically Target Duck Hepatitis B Virus Covalently Closed Circular DNA Inhibit Viral Transcription in Tissue Culture
Authors: Zimmerman Kimberley A. , Fischer Karl P. , Joyce Michael A. , Tyrrell D. Lorne J. 
Published: June 2008

ABSTRACT
Duck hepatitis B virus (DHBV) is a model virus for human hepatitis B virus (HBV), which infects approximately 360 million individuals worldwide. Nucleoside analogs can decrease virus production by inhibiting the viral polymerase; however, complete clearance by these drugs is not common because of the persistence of the HBV episome. HBV DNA is present in the nucleus as a covalently closed circular (cccDNA) form, where it drives viral transcription and progeny virus production. cccDNA is not the direct target of antiviral nucleoside analogs and is the source of HBV reemergence when antiviral therapy is stopped. To target cccDNA, six different zinc finger proteins (ZFP) were designed to bind DNA sequences in the DHBV enhancer region. After the binding kinetics were assessed by using electrophoretic mobility shift assays and surface plasmon resonance, two candidates with dissociation constants of 12.3 and 40.2 nM were focused on for further study. The ZFPs were cloned into a eukaryotic expression vector and cotransfected into longhorn male hepatoma cells with the plasmid pDHBV1.3, which replicates the DHBV life cycle. In the presence of each ZFP, viral RNA was significantly reduced, and protein levels were dramatically decreased. As a result, intracellular viral particle production was also significantly decreased. In summary, designed ZFPs are able to bind to the DHBV enhancer and interfere with viral transcription, resulting in decreased production of viral products and progeny virus genomes.
Adeno-Associated Virus Vector Genomes Persist as Episomal Chromatin in Primate Muscle
Authors: Penaud-Budloo Magalie , Le Guiner Caroline , Nowrouzi Ali , Toromanoff Alice , Chérel Yan , Chenuaud Pierre , Schmidt Manfred , von Kalle Christof , Rolling Fabienne , Moullier Philippe , Snyder Richard O. 
Published: June 2008

ABSTRACT

Recombinant adeno-associated virus (rAAV) vectors are capable of mediating long-term gene expression following administration to skeletal muscle. In rodent muscle, the vector genomes persist in the nucleus in concatemeric episomal forms. Here, we demonstrate with nonhuman primates that rAAV vectors integrate inefficiently into the chromosomes of myocytes and reside predominantly as episomal monomeric and concatemeric circles. The episomal rAAV genomes assimilate into chromatin with a typical nucleosomal pattern. The persistence of the vector genomes and gene expression for years in quiescent tissues suggests that a bona fide chromatin structure is important for episomal maintenance and transgene expression. These findings were obtained from primate muscles transduced with rAAV1 and rAAV8 vectors for up to 22 months after intramuscular delivery of 5 × 10
12
viral genomes/kg. Because of this unique context, our data, which provide important insight into in situ vector biology, are highly relevant from a clinical standpoint.
Structural Variations in Species B Adenovirus Fibers Impact CD46 Association
Authors: Pache Lars , Venkataraman Sangita , Reddy Vijay S. , Nemerow Glen R. 
Published: June 2008

ABSTRACT
A majority of species B adenoviruses (Ads) use CD46 as their primary receptor; however, the precise mechanisms involved in the binding of different Ad types to CD46 have not been resolved. Although previous studies indicate close similarities between two members of species B2 Ads in their usage of CD46, our current investigations revealed a surprisingly low CD46 binding affinity of the species B1 Ad16 fiber knob (equilibrium dissociation constant of 437 nM). We determined the crystal structure of the Ad16 fiber knob and constructed a model of this protein in complex with CD46. A comparison of this model to that of the CD46-Ad11 complex revealed structural differences in the FG and IJ loops that are part of the CD46 binding site. An analysis of a panel of recombinant fiber knobs with mutations targeting these regions in Ad16 and Ad11 uncovered a major contribution of the FG loop on CD46 binding. Two extra residues in the FG loop of the Ad16 fiber significantly reduce receptor interaction. Although avidity effects permit the use of CD46 on host cells by Ad16, virus binding occurs with lower efficiency than with B2 Ad types. The longer FG loop of the Ad16 fiber knob also is shared by other species B1 Ad fibers and, thus, may contribute to the low CD46 binding efficiencies observed for these Ad types. Our findings provide a better understanding of how different Ad types associate with CD46 and could aid in the selection of specific Ad fibers for more efficient Ad gene delivery vectors.
Influenza Virus Infection Augments NK Cell Inhibition through Reorganization of Major Histocompatibility Complex Class I Proteins
Authors: Achdout Hagit , Manaster Irit , Mandelboim Ofer 
Published: June 2008

ABSTRACTThe killing by natural killer (NK) cells is regulated by inhibitory, costimulatory, and activating receptors. The inhibitory receptors recognize mainly major histocompatibility complex (MHC) class I molecules, while the activating NK receptors recognize stress-induced ligands and viral products. Thus, changes in the expression of the various inhibitory and activating ligands will determine whether target cells will be killed or protected. Here, we demonstrate that after influenza virus infection the binding of the two NK inhibitory receptors, KIR2DL1 and the LIR1, to the infected cells is specifically increased. The increased binding occurs shortly after the influenza virus infection, prior to the increased recognition of the infected cells by the NK activating receptor, NKp46. We also elucidate the mechanism responsible for this effect and demonstrate that, after influenza virus infection, MHC class I proteins redistribute on the cell surface and accumulate in the lipid raft microdomains. Such redistribution allows better recognition by the NK inhibitory receptors and consequently increases resistance to NK cell attack. In contrast, T-cell activity was not influenced by the redistribution of MHC class I proteins. Thus, we present here a novel mechanism, developed by the influenza virus, of inhibition of NK cell cytotoxicity, through the reorganization of MHC class I proteins on the cell surface.
Structure, Function, and Evolution of Bacterial ATP-Binding Cassette Systems
Authors: Davidson Amy L. , Dassa Elie , Orelle Cedric , Chen Jue 
Published: June 2008

SUMMARYATP-binding cassette (ABC) systems are universally distributed among living organisms and function in many different aspects of bacterial physiology. ABC transporters are best known for their role in the import of essential nutrients and the export of toxic molecules, but they can also mediate the transport of many other physiological substrates. In a classical transport reaction, two highly conserved ATP-binding domains or subunits couple the binding/hydrolysis of ATP to the translocation of particular substrates across the membrane, through interactions with membrane-spanning domains of the transporter. Variations on this basic theme involve soluble ABC ATP-binding proteins that couple ATP hydrolysis to nontransport processes, such as DNA repair and gene expression regulation. Insights into the structure, function, and mechanism of action of bacterial ABC proteins are reported, based on phylogenetic comparisons as well as classic biochemical and genetic approaches. The availability of an increasing number of high-resolution structures has provided a valuable framework for interpretation of recent studies, and realistic models have been proposed to explain how these fascinating molecular machines use complex dynamic processes to fulfill their numerous biological functions. These advances are also important for elucidating the mechanism of action of eukaryotic ABC proteins, because functional defects in many of them are responsible for severe human inherited diseases.
Groundwater microbiological quality in Canadian drinking water municipal wells
Authors: Locas Annie , Barthe Christine , Margolin Aaron B. , Payment Pierre 
Published: June 2008

To verify previous conclusions on the use of bacterial indicators suggested in regulations and to investigate virological quality of groundwater, a 1-year study was undertaken on groundwater used as a source of drinking water in 3 provinces in Canada. Raw water from 25 municipal wells was sampled during a 1-year period for a total of 167 samples. Twenty-three sites were selected on the basis of their excellent historical bacteriological water quality data, and 2 sites with known bacteriological contamination were selected as positive controls. Water samples were analyzed for general water quality indicators (aerobic endospores, total coliforms), fecal indicators ( Escherichia coli , enterococci, somatic and male-specific coliphages), total culturable human enteric viruses (determined by cell culture and immunoperoxidase), noroviruses (analyzed by reverse-transcriptase – polymerase chain reaction (RT–PCR)), adenovirus types 40 and 41 (analyzed by integrated cell culture (ICC) – PCR), and enteroviruses and reoviruses types 1, 2, and 3 (analyzed by ICC–RT–PCR). General water quality indicators were found very occasionally at the clean sites but were frequently present at the 2 contaminated sites. Only one of 129 samples from the 23 clean sites was positive for enterococci. These results confirm the value of raw water quality historical data to detect source water contamination affecting wells that are vulnerable. Samples from the 2 contaminated sites confirmed the frequent presence of fecal indicators: E. coli was found in 20/38 samples and enterococci in 12/38 samples. Human enteric viruses were not detected by cell culture on MA-104 cells nor by immunoperoxidase detection in any sample from the clean sites but were found at one contaminated site. By ICC–RT–PCR and ICC–PCR, viruses were found by cytopathic effect in one sample from a clean site and they were found in 3 samples from contaminated sites. The viruses were not detected by the molecular methods but were confirmed as picornaviruses by electron microscopy. Noroviruses were not detected in any samples. The results obtained reinforce the value of frequent sampling of raw water using simple parameters: sampling for total coliforms and E. coli remains the best approach to detect contamination of source water by fecal pollutants and accompanying pathogens. The absence of total coliforms at a site appears to be a good indication of the absence of human enteric viruses.