bluuebunny/crossref_metadata_2025_split huggingface dataset:
Gene Expression Changes in Peripheral Blood Mononuclear Cells during Measles Virus Infection
Authors: Zilliox Michael J. , Moss William J. , Griffin Diane E. 
Published: May 2007

ABSTRACTMeasles virus continues to cause morbidity and mortality despite the existence of a safe and efficacious vaccine. Measles is associated with induction of both a long-lived protective immune response and immunosuppression. To gain insight into immunological changes during measles virus infection, we examined gene expression in blood mononuclear cells from children with acute measles and children in the convalescent phase compared to uninfected control children. There were 13 significantly upregulated and 206 downregulated genes. Upregulated genes included the immune regulatory molecules interleukin 1β (IL-1β), CIAS-1, tumor necrosis factor alpha, PDE4B, PTGS2, IL-8, CXCL2, CCL4, ICAM-1, CD83, GOS-2, IER3 (IEX-1), and TNFAIP3 (A20). Plasma levels of IL-1β and IL-8 were elevated during measles virus infection. Downregulated genes mainly involved three gene ontology biological processes, transcription, signal transduction, and the immune response, and included IL-16 and cell surface receptors IL-4R, IL-6R, IL-7R, IL-27RA, CCR2, and CCR7. Most mRNAs had not returned to control values 1 month after discharge, consistent with prolonged immune response abnormalities during measles virus infection.
Identification of a Novel Immunosubversion Mechanism Mediated by a Virologue of the B-Lymphocyte Receptor TACI
Authors: Grant Jason R. , Moise Alexander R. , Jefferies Wilfred A. 
Published: May 2007

ABSTRACTTACI (transmembrane activator and calcium modulator and cyclophilin ligand [CAML] interactor) is a part of a novel network of ligands and receptors involved in B-cell survival and isotype switching. The TACI protein mediates its effects through CAML, an endoplasmic reticulum (ER)-localized protein that controls Ca2+efflux. The adenovirus E3-6.7K protein prevents inflammatory responses and also confers resistance from a variety of apoptotic stimuli and maintains ER Ca2+homeostasis; however, the mechanism of action is unknown. Here, we provide evidence that E3-6.7K shares sequence homology with TACI and inhibits apoptosis and ER Ca2+efflux through an interaction with CAML, a Ca2+-modulating protein. We demonstrate a direct interaction between E3-6.7K and CAML and reveal that the two proteins colocalize in an ER-like compartment. Furthermore, the interaction between the two proteins is localized to the N-terminal domain of CAML and to a 22-amino-acid region near the C terminus of E3-6.7K termed the CAML-binding domain (CBD). Mutational analysis of the CBD showed that an interaction with CAML is required for E3-6.7K to inhibit thapsigargin-induced apoptosis and ER Ca2+efflux. E3-6.7K appears to be the first virologue of TACI to be identified. It targets CAML in a novel immunosubversive mechanism to alter ER Ca2+homeostasis, which consequently inhibits inflammation and protects infected cells from apoptosis.
Parasite-Induced Chronic Inflammation Is Not Exacerbated by Immunotherapy before or duringTrypanosoma cruziInfection
Authors: Duthie Malcolm S. , Kahn Maria , Zakayan Arsen , White Maria , Kahn Stuart J. 
Published: May 2007

ABSTRACTTrypanosoma cruziinfection causes Chagas' disease, a chronic inflammatory disease. The specific inflammatory responses that cause Chagas' disease remain unclear, but data argue that parasites that persist in the host stimulate chronic self-damaging immune responses. BecauseT. cruziappears to stimulate self-damaging responses, the enthusiasm to develop vaccines that boost antiparasite responses that might increase self-damaging responses has been limited. We previously demonstrated that immunization with aT. cruzi trans-sialidase protein or adoptive transfer oftrans-sialidase-specific T-cell clones decreased parasitemia, morbidity, and mortality. Here we report that immunization or adoptive transfer with the protein or clones, before or duringT. cruziinfection, boosts the anti-T. cruziimmune response without exacerbating acute or chronic tissue inflammation. These results argue that prophylactic and therapeutic immunotherapy for Chagas' disease can be developed safely.
Human Polyomavirus Type 1 (BK Virus) Agnoprotein Is Abundantly Expressed but Immunologically Ignored
Authors: Leuenberger David , Andresen Per Arne , Gosert Rainer , Binggeli Simone , Ström Erik H. , Bodaghi Sohrab , Rinaldo Christine Hanssen , Hirsch Hans H. 
Published: May 2007

ABSTRACT
Impaired BK virus (BKV)-specific immunity is a key risk factor of polyomavirus-associated nephropathy. We hypothesized that BKV agnoprotein might constitute an important immune target, as it is highly expressed after infection in vitro. We demonstrate abundant expression of BKV agnoprotein in vivo by immunostaining of kidney transplant (KT) biopsy specimens. Antibody responses to the recombinant affinity-purified BKV agnoprotein, large tumor (LT), and VP1 antigens in 146 sera from 38 KT patients and in 19 sera from 16 healthy donors (HD) were compared by enzyme immunoassay. In HD, low titers of anti-agnoprotein immunoglobulin G (IgG) were found in 15% of sera, compared to 41% for anti-LT antigen and 63% for anti-VP1. No anti-BKV IgM was detectable. In KT patients, anti-agnoprotein IgG and IgM were found in 8% and 3.6% of sera, compared to 63% and 18% for anti-LT IgG and IgM and 80% and 41% for anti-VP1 IgG and IgM, respectively. Anti-LT antigen and anti-VP1, but not anti-agnoprotein, activities increased during and after BKV viremia in KT patients. To investigate specific cellular immune responses, we compared levels of gamma interferon production in peripheral blood mononuclear cells (PBMC) of 10 HD and 30 KT patients by enzyme-linked immunospot assay. In HD, the median numbers of gamma interferon spot-forming units per million PBMC for the agnoprotein, LT antigen, and VP1 peptides were 1, 23, and 25, respectively, whereas the responses in KT patients were 2, 24, and 99, respectively. We conclude that BKV agnoprotein, though abundantly expressed in vivo, is poorly recognized immunologically.
Clonal Distribution of Superantigen Genes in ClinicalStaphylococcus aureusIsolates
Authors: Holtfreter S. , Grumann D. , Schmudde M. , Nguyen H. T. T. , Eichler P. , Strommenger B. , Kopron K. , Kolata J. , Giedrys-Kalemba S. , Steinmetz I. , Witte W. , Bröker B. M. 
Published: May 2007

ABSTRACTStaphylococcus aureusis both a successful human commensal and a major pathogen. The elucidation of the molecular determinants of virulence, in particular assessment of the contributions of the genetic background versus those of mobile genetic elements (MGEs), has proved difficult in this variable species. To address this, we simultaneously determined the genetic backgrounds (spatyping) and the distributions of all 19 known superantigens and the exfoliative toxins A and D (multiplex PCR) as markers for MGEs. Methicillin- sensitiveS. aureusstrains from Pomerania, 107 nasal and 88 blood culture isolates, were investigated. All superantigen-encoding MGEs were linked more or less tightly to the genetic background. Thus, eachS. aureusclonal complex was characterized by a typical repertoire of superantigen and exfoliative toxin genes. However, within eachS. aureusclonal complex and even within the samespatype, virulence gene profiles varied remarkably. Therefore, virulence genes of nasal and blood culture isolates were separately compared in each clonal complex. The results indicated a role in infection for the MGE harboring the exfoliative toxin D gene. In contrast, there was no association of superantigen genes with bloodstream invasion. In summary, we show here that the simultaneous assessment of virulence gene profiles and the genetic background increases the discriminatory power of genetic investigations into the mechanisms ofS. aureuspathogenesis.
Evaluation of the GenoType MTBDRplus Assay for Rifampin and Isoniazid Susceptibility Testing of
Mycobacterium tuberculosis
Strains and Clinical Specimens
Authors: Hillemann Doris , Rüsch-Gerdes Sabine , Richter Elvira 
Published: May 2007

ABSTRACT

The new GenoType MTBDRplus assay (Hain Lifescience GmbH, Nehren, Germany) was tested with 125 clinical isolates and directly with 72 smear-positive sputum specimens for its ability to detect rifampin (RMP) and isoniazid (INH) resistance in
Mycobacterium tuberculosis
complex (MTBC) strains. In total, 106 RMP
r
/INH
r
, 10 RMP
s
/INH
r
, and 80 RMP
s
/
INH
s
MTBC strains were comparatively analyzed with the new and the old MTBDR assays. Besides the detection of mutations within the 81-bp hot spot region of
rpoB
and
katG
codon 315, the GenoType MTBDRplus assay is designed to detect mutations in the regulatory region of
inhA
. The applicability of the new assay directly to specimens was shown, since 71 of 72 results for smear-positive sputa and all 125 results for clinical isolates were interpretable and no discrepancies compared with the results of real-time PCR or DNA sequencing were obtained. In comparison to conventional drug susceptibility testing, both assays were able to identify RMP resistance correctly in 74 of 75 strains (98.7%) and 30 of 31 specimens (96.8%). The misidentification of RMP resistance was obtained for two strains containing
rpoB
P533L mutations. Compared to the old MTBDR assay, the new GenoType MTBDRplus assay enhanced the rate of detection of INH resistance from 66 (88.0%) to 69 (92.0%) among the 75 INH-resistant strains and 36 (87.8%) to 37 (90.2%) among the 41 specimens containing INH-resistant strains. Thus, the new GenoType MTBDRplus assay represents a reliable and upgraded tool for the detection of INH and RMP resistance in strains or directly from smear-positive specimens.
A Mutation on Influenza C Virus M1 Protein Affects Virion Morphology by Altering the Membrane Affinity of the Protein
Authors: Muraki Yasushi , Murata Toshio , Takashita Emi , Matsuzaki Yoko , Sugawara Kanetsu , Hongo Seiji 
Published: May 2007

ABSTRACT

Reverse genetics has been documented for influenza A, B, and Thogoto viruses belonging to the family
Orthomyxoviridae
. We report here the reverse genetics of influenza C virus, another member of this family. The seven viral RNA (vRNA) segments of C/Ann Arbor/1/50 were expressed in 293T cells from cloned cDNAs, together with nine influenza C virus proteins. At 48 h posttransfection, the infectious titer of the culture supernatant was determined to be 2.51 × 10
3
50% egg infectious doses/ml, which is lower than the number of influenza C virus-like particles (VLPs) (10
6
/ml) generated using the same system. By generating influenza C VLPs containing a given vRNA segment, we showed that each of the vRNA segments was similarly synthesized in the plasmid-transfected cells but that some segments were less efficiently incorporated into the VLPs. This finding leads us to speculate that the differences in incorporation efficiency into VLPs between segments might be a reason for the inefficient production of infectious viruses. Second, we generated a mutant recombinant virus, rMG96A, which possesses an Ala→Thr mutation at residue 24 of the M1 protein, a substitution demonstrated to be involved in the morphology (filamentous or spherical) of the influenza C VLPs. As expected, rMG96A exhibited a spherical morphology, whereas recombinant wild-type of C/Ann Arbor/1/50, rWT, exhibited a mainly filamentous morphology. Membrane flotation analysis of the cells infected with rWT or rMG96A revealed a difference in the ratio of membrane-associated M1 proteins, suggesting that the affinity of M1 protein to the cell membrane is a determinant for virion morphology.
Genetic Adaptation to Untranslated Region-Mediated Enterovirus Growth Deficits by Mutations in the Nonstructural Proteins 3AB and 3CD
Authors: de Sessions Paola Florez , Dobrikova Elena , Gromeier Matthias 
Published: May 2007

ABSTRACT

Both untranslated regions (UTRs) of plus-strand RNA virus genomes jointly control translation and replication of viral genomes. In the case of the
Enterovirus
genus of the
Picornaviridae
family, the 5′UTR consists of a cloverleaf-like terminus preceding the internal ribosomal entry site (IRES) and the 3′ terminus is composed of a structured 3′UTR and poly(A). The IRES and poly(A) have been implicated in translation control, and all UTR structures, in addition to
cis
-acting genetic elements mapping to the open reading frame, have been assigned roles in RNA replication. Viral UTRs are recognized by viral and host cell RNA-binding proteins that may codetermine genome stability, translation, plus- and minus-strand RNA replication, and scaffolding of viral replication complexes within host cell substructures. In this report, we describe experiments with coxsackie B viruses with a cell type-specific propagation deficit in Sk-N-Mc neuroblastoma cells conferred by the combination of a heterologous IRES and altered 3′UTR. Serial passage of these constructs in Sk-N-Mc cells yielded genetic adaptation by mutations within the viral nonstructural proteins 3A and 3C. Our data implicate 3A and/or 3C or their precursors 3AB and/or 3CD in a functional complex with the IRES and 3′UTR that drives viral propagation. Adaptation to neuroblastoma cells suggests an involvement of cell type-specific host factors or the host cell cytoplasmic milieu in this phenomenon.
Dynein-Dependent Transport of the Hantaan Virus Nucleocapsid Protein to the Endoplasmic Reticulum-Golgi Intermediate Compartment
Authors: Ramanathan Harish N. , Chung Dong-Hoon , Plane Steven J. , Sztul Elizabeth , Chu Yong-kyu , Guttieri Mary C. , McDowell Michael , Ali Georgia , Jonsson Colleen B. 
Published: May 2007

ABSTRACT

In contrast to most negative-stranded RNA viruses, hantaviruses and other viruses in the family
Bunyaviridae
mature intracellularly, deriving the virion envelope from the endoplasmic reticulum (ER) or Golgi compartment. While it is generally accepted that Old World hantaviruses assemble and bud into the Golgi compartment, some studies with New World hantaviruses have raised the possibility of maturation at the plasma membrane as well. Overall, the steps leading to virion assembly remain largely undetermined for hantaviruses. Because hantaviruses do not have matrix proteins, the nucleocapsid protein (N) has been proposed to play a key role in assembly. Herein, we examine the intracellular trafficking and morphogenesis of the prototype Old World hantavirus, Hantaan virus (HTNV). Using confocal microscopy, we show that N colocalized with the ER-Golgi intermediate compartment (ERGIC) in HTNV-infected Vero E6 cells, not with the ER, Golgi compartment, or early endosomes. Brefeldin A, which effectively disperses the ER, the ERGIC, and Golgi membranes, redistributed N with the ERGIC, implicating membrane association; however, subcellular fractionation experiments showed the majority of N in particulate fractions. Confocal microscopy revealed that N was juxtaposed to and distributed along microtubules and, over time, became surrounded by vimentin cages. To probe cytoskeletal association further, we probed trafficking of N in cells treated with nocodazole and cytochalasin D, which depolymerize microtubules and actin, respectively. We show that nocodazole, but not cytochalasin D, affected the distribution of N and reduced levels of intracellular viral RNA. These results suggested the involvement of microtubules in trafficking of N, whose movement could occur via molecular motors such as dynein. Overexpression of dynamitin, which is associated with dynein-mediated transport, creates a dominant-negative phenotype blocking transport on microtubules. Overexpression of dynamitin reduced N accumulation in the perinuclear region, which further supports microtubule components in N trafficking. The combined results of these experiments support targeting of N to the ERGIC prior to its movement to the Golgi compartment and the requirement of an intact ERGIC for viral replication and, thus, the possibility of virus factories in this region.
Distinct Gene Expression Profiling after Infection of Immature Human Monocyte-Derived Dendritic Cells by the Attenuated Poxvirus Vectors MVA and NYVAC
Authors: Guerra Susana , Nájera José Luis , González José Manuel , López-Fernández Luis A. , Climent Nuria , Gatell José M. , Gallart Teresa , Esteban Mariano 
Published: May 2007

ABSTRACTAlthough recombinants based on the attenuated poxvirus vectors MVA and NYVAC are currently in clinical trials, the nature of the genes triggered by these vectors in antigen-presenting cells is poorly characterized. Using microarray technology and various analysis conditions, we compared specific changes in gene expression profiling following MVA and NYVAC infection of immature human monocyte-derived dendritic cells (MDDC). Microarray analysis was performed at 6 h postinfection, since these viruses induced extensive cytopathic effects, rRNA breakdown, and apoptosis at late times postinfection. MVA- and NYVAC-infected MDDC shared upregulation of 195 genes compared to uninfected cells: MVA specifically upregulated 359 genes, and NYVAC upregulated 165 genes. Microarray comparison of NYVAC and MVA infection revealed 544 genes with distinct expression patterns after poxvirus infection and 283 genes specifically upregulated after MVA infection. Both vectors upregulated genes for cytokines, cytokine receptors, chemokines, chemokine receptors, and molecules involved in antigen uptake and processing, including major histocompatibility complex genes. mRNA levels for interleukin 12β (IL-12β), beta interferon, and tumor necrosis factor alpha were higher after MVA infection than after NYVAC infection. The expression profiles of transcription factors such as NF-κB/Rel and STAT were regulated similarly by both viruses; in contrast, OASL, MDA5, and IRIG-I expression increased only during MVA infection. Type I interferon, IL-6, and Toll-like receptor pathways were specifically induced after MVA infection. Following MVA or NYVAC infection in MDDC, we found similarities as well as differences between these virus strains in the expression of cellular genes with immunological function, which should have an impact when these vectors are used as recombinant vaccines.
General Strategy for Decoration of Enveloped Viruses with Functionally Active Lipid-Modified Cytokines
Authors: Kueng Hans J. , Leb Victoria M. , Haiderer Daniela , Raposo Graça , Thery Clotilde , Derdak Sophia V. , Schmetterer Klaus G. , Neunkirchner Alina , Sillaber Christian , Seed Brian , Pickl Winfried F. 
Published: May 2007

ABSTRACTViral particles preferentially incorporate extra- and intracellular constituents of host cell lipid rafts, a phenomenon central to pseudotyping. Based on this mechanism, we have developed a system for the predictable decoration of enveloped viruses with functionally active cytokines that circumvents the need to modify viral proteins themselves. Human interleukin-2 (hIL-2), hIL-4, human granulocyte-macrophage colony-stimulating factor (hGM-CSF), and murine IL-2 (mIL-2) were used as model cytokines and fused at their C terminus to the glycosylphosphatidylinositol (GPI) acceptor sequence of human Fcγ receptor III (CD16b). We show here that genetically modified cytokines are all well expressed on 293 producer cells. However, only molecules equipped with GPI anchors but not those linked to transmembrane/intracellular regions of type I membrane proteins are efficiently targeted to lipid rafts and consequently to virus-like particles (VLP) induced by Moloney murine leukemia virus Gag-Pol. hIL-4::GPI and hGM-CSF::GPI coexpressed on VLP were found to differentiate monocytes towards dendritic cells. Apart from myeloid-committed cell types, VLP-bound cytokines also act efficiently on lymphocytes. hIL-2::GPI strongly costimulated T-cell receptor (TCR)/CD3 dependent T-cell activation in vitro and mIL-2::GPI-coactivated antigen-specific T cells in vivo. On a molar basis, the functional activity of VLP-bound hIL-2::GPI was found to be comparable to that of soluble hIL-2. VLP decorated with hIL-2::GPI and coexpressing a TCR/CD3 ligand have an IL-2-specific activity of 5 × 104units/mg protein. Virus particles decorated with lipid-modified cytokines might help to improve viral strains for vaccination purposes, the propagation of factor-dependent cell types, as well as gene transfer by viral systems in the future.
Enterovirus 70 Receptor Utilization Is Controlled by Capsid Residues That Also Regulate Host Range and Cytopathogenicity
Authors: Kim Melissa Stewart , Racaniello Vincent R. 
Published: May 2007

ABSTRACT
Enterovirus type 70, an etiologic agent of acute hemorrhagic conjunctivitis, may bind different cellular receptors depending on cell type. To understand how EV70-receptor interaction is controlled, we studied two variants of the virus with distinct receptor utilization. EV70-Rmk, derived by passage in rhesus monkey kidney cells, replicates poorly in HeLa cells and does not cause cytopathic effects. Decay accelerating factor (DAF) is not a cell receptor for EV70-Rmk. Passage of EV70-Rmk in HeLa cells lead to isolation of EV70-Dne, which does not replicate in rhesus monkey kidney cells but grows to high titers in HeLa cells and causes cytopathic effects. DAF is sufficient for cell entry of EV70-Dne. EV70-Rmk replicates in human eye and brain-derived cell lines, whereas the Dne strain replicates only in HeLa cells and in conjunctiva-derived 15C4 cells. The two EV70 strains differ by five amino acid changes in the viral capsid. Single substitution of four of the five EV70-Rmk amino acids with the residue from EV70-Dne leads to lytic replication in HeLa cells. Conversely, substitution of any of the five EV70-Dne amino acids with the EV70-Rmk amino acid does not alter replication in HeLa cells. Three of these capsid amino acids are predicted to be located in the canyon encircling the fivefold axis of symmetry, one amino acid is found at the fivefold axis of symmetry, and one is located the interior of the capsid. The five EV70 residues define a region of the capsid that controls viral host range, DAF utilization, and cytopathogenicity.
The 5S DNA sequences in Hordeum bogdanii and in the H. brevisubulatum complex, and the evolution and the geographic dispersal of the diploidHordeumspecies (Triticeae: Poaceae)
Authors: Baum Bernard R. , Johnson Douglas A. 
Published: May 2007

The molecular diversity of 5S rDNA from the closely related Asiatic diploid species, Hordeum bogdanii and the H. brevisubulatum complex has been catalogued and analysed. As in previous studies in Hordeum , we found that the sequences are constrained in such an manner that unit classes can be defined. The long H1 unit class, known to occur in all Eurasian species, was frequently found in these 2 taxa. In addition, we identified a new unit class, called the short H3 to reflect the H genome found in these 2 taxa. Although the 2 taxa are very close morphologically, the variation in the long H1 DNA units is constrained to such a great degree that, in many cases, the accessions in a unit class from a single species are clustered. In H. bogdanii, the majority of the sequences are grouped in this manner, whereas in the H. brevisubulatum complex, the tendency to be constrained is lower in some but not all subspecies. These results support keeping H. brevisubulatum ssp. violaceum and ssp. iranicum as 1 species with the long H1 and short H1 unit classes, while retaining ssp. nevskianum and ssp. turkestanicum in the H. brevisubulatum complex. We have summarized our work on the presence/absence of the 10 unit classes found in all diploid species of Hordeum. A phylogenetic analysis, based strictly on the presence/absence of unit classes, indicated clearly that all the South American diploids and all the North American diploids possess long H2 and long Y2 unit classes and, except for H. californicum and H. pusillum, which contain long H1 in addition to the long H2 and long Y2 classes, are devoid of the long H1 unit class. This suggests that the gene gain/loss process from a common ancestor has been concomitant with intercontinental dispersal between the Old and the New Worlds.