A5041933832- Viral Infections and Immunology Research
- interferon and immune responses
- Animal Virus Infections Studies
- Plant Virus Research Studies
- Cytokine Signaling Pathways and Interactions
- Viral gastroenteritis research and epidemiology
- Yersinia bacterium, plague, ectoparasites research
- RNA regulation and disease
- Bacterial Genetics and Biotechnology
- Immune Response and Inflammation
- RNA and protein synthesis mechanisms
- Immune Cell Function and Interaction
- Vibrio bacteria research studies
- Viral Infections and Vectors
- Herpesvirus Infections and Treatments
- Virus-based gene therapy research
- RNA Research and Splicing
- Chromosomal and Genetic Variations
- Advanced biosensing and bioanalysis techniques
- Education, sociology, and vocational training
- Systemic Lupus Erythematosus Research
- Mosquito-borne diseases and control
- Cytomegalovirus and herpesvirus research
- Hepatitis Viruses Studies and Epidemiology
- Salmonella and Campylobacter epidemiology
de Duve Institute
2016-2025
UCLouvain
2014-2024
Ghent University Hospital
2024
Cancer Research Institute Ghent
2024
Veterinary and Agrochemical Research Centre
2014
University of Freiburg
2009
Radboud University Nijmegen
2009
Radboud University Medical Center
2009
Institut Pasteur
1994-1999
Interferons (IFN) exert antiviral, immunomodulatory and cytostatic activities. IFN-alpha/beta (type I IFN) IFN-lambda III bind distinct receptors, but regulate similar sets of genes exhibit strikingly biological We analyzed to what extent the systems overlap in vivo terms expression response. observed a certain degree tissue specificity production IFN-lambda. In brain, was readily produced after infection with various RNA viruses, whereas low this organ. liver, virus induced both genes....
ABSTRACT Virus-infected cells secrete a broad range of interferons (IFN) which confer resistance to yet uninfected by triggering the synthesis antiviral factors. The relative contributions various IFN subtypes innate immunity against virus infections remain elusive. IFN-α, IFN-β, and other type I molecules signal through common, universally expressed cell surface receptor, whereas III (IFN-λ) uses distinct cell-type-specific receptor complex for signaling. Using mice lacking functional...
Upon incubation at 37 degrees C in the absence of Ca2+ ions, pathogenic strains genus Yersinia cease growing and produce large amounts a series plasmid-encoded proteins involved pathogenicity. These proteins, called Yops (for outer membrane proteins), are detected both fraction culture supernatant. We present here nucleotide sequence genes yop20 yop25 from enterocolitica O:9. Protein Yop25 is very similar to YopE, corresponding protein pestis, Y. pseudotuberculosis, O:8 (A. Forsberg H....
Type I and type III IFNs bind to different cell-surface receptors but induce identical signal transduction pathways, leading the expression of antiviral host effector molecules. Despite fact that IFN (IFN-λ) has been shown predominantly act on mucosal organs, in vivo infection studies have failed attribute a specific, nonredundant function. Instead, predominant role was observed, which explained by ubiquitous receptor. Here we comparatively analyzed functional IFN-λ receptor signaling innate...
Upon incubation at 37 degrees C in the absence of Ca2+ ions, pathogenic yersiniae release large amounts pYV plasmid-encoded proteins called Yops that are involved pathogenesis. Yersinia enterocolitica also expresses an outer membrane protein is considered adhesin and YadA (previously P1 or YopA). The production coordinately regulated by a 20-kb region plasmid referred to as dependence containing least four loci virA, virB, virC, virF. virF gene encodes key transcriptional activator yop...
Interferon (IFN)-lambda 1, -lambda 2, and 3 are the latest members of class II cytokine family were shown to have antiviral activity. Their receptor is composed two chains, interleukin-28R/likely interleukin or 2 (IL-28R/LICR2) IL-10R beta, mediates tyrosine phosphorylation STAT1, STAT2, STAT3, STAT5. Here, we show that activation this by IFN-lambda 1 can also inhibit cell proliferation induce STAT4 phosphorylation, further extending functional similarities with type I IFNs. We used...
Pathogenic yersiniae secrete anti-host proteins called Yops, by a recently discovered Sec-independent pathway. The Yops do not have classical signal peptide at their N terminus and they are processed during membrane translocation. secretion domain is nevertheless contained in N-terminal part but these domains resemble each other the different Yops. We previously shown that YopE requires SycE, 15-kDa acidic protein acting as specific cytosolic chaperone. Here we show gene downstream from yopH...
Virulent yersiniae (Yersinia pestis, Y. pseudotuberculosis, and enterocolitica) restrict their growth at 37 degrees C in rich medium deprived of calcium. This property, called calcium dependency, correlates with the secretion Yersinia outer membrane proteins (Yops) pathogenicity. It is mediated by a 70-kilobase plasmid pYV. The structural genes Yops (yop genes), as well involved control expression (vir have been localized on In this communication we show that virF encodes transcriptional...
Type I interferons, also referred to as IFN-α/β, form the first line of defense against viral infections. Major IFN-α/β producers in periphery are plasmacytoid dendritic cells (pDCs). Constitutive expression IFN regulatory factor (IRF)-7 enables pDCs rapidly synthesize large amounts after infection. In central nervous system (CNS), considered be absent from parenchyma, and little is known about producing IFN-α/β. The study presented here aimed identify CNS vivo infection by neurotropic...
After incubation at 37 degrees C in the absence of Ca2+ ions, pathogenic strains Yersinia spp. release large amounts a set plasmid-encoded proteins called Yops. The secretion these proteins, involved pathogenicity, occurs via mechanism that involves neither removal signal sequence nor recognition C-terminal domain. Analysis deletion mutants allowed domain to be localized within 48 N-terminal amino acids protein YopH, 98 residues YopE, and 76 YopQ. Comparison regions failed reveal any...
Summary The virulence functions of Yersinia enterocolitica include the pYV‐encoded Yop proteins and YadA adhesin as well chromosome‐encoded enterotoxin, Yst. yop yadA genes form a temperature‐activated regulon controlled by transcriptional activator VirF. Gene virF , also localized on pYV, is itself thermoinduced in absence other pYV genes. enterotoxin ysf gene silent some collection strains including strain W22703. This paper describes two Tn5‐Tc1 chromosomal insertion mutants W22703...
ABSTRACT Mouse and human genomes carry more than a dozen genes coding for closely related alpha interferon (IFN-α) subtypes. IFN-α, as well IFN-β, IFN-κ, IFN-ε, limitin, are thought to bind the same receptor, raising question of whether different IFN subtypes possess specific functions. As some confusion existed in identity characteristics mouse IFN-α subtypes, availability data from genome sequence prompted us characterize murine family. A total 14 were detected genome, addition three...
ABSTRACT La Crosse virus (LACV) is a mosquito-transmitted member of the Bunyaviridae family that causes severe encephalitis in children. For LACV nonstructural protein NSs, previous overexpression studies with mammalian cells had suggested two different functions, namely induction apoptosis and inhibition RNA interference (RNAi). Here, we demonstrate mosquito persistently infected do not undergo mount specific RNAi response. Recombinant viruses either express (rLACV) or lack (rLACVdelNSs)...
<h3>Objective</h3> The hepatitis E virus (HEV) is responsible for approximately 20 million infections per year worldwide. Although most infected people can spontaneously clear an HEV infection, immune-compromised individuals may evolve towards chronicity. Chronic infection be cured using ribavirin, but viral isolates with low ribavirin sensitivity have recently been identified. some cultured <i>in vitro, in vivo</i> studies are essentially limited to primates and pigs. Since the use of these...
This paper describes the mutagenesis of pYV plasmid from Yersinia enterocolitica W22703 (serotype O:9) with Tn2507, a new element generating operon fusions. Analysis mutants allowed identification an additional Yop protein called Yop20 and mapping yop20, yop44, yop48, lcrV, gene encoding V antigen. The last appeared to be part that also may contain yop37 yop44. At 37 degrees C, affected in this grew poorly, irrespective presence Ca2+, or they even died Ca2+. is thus involved regulation by we...
Viral infection of mammalian cells triggers the synthesis and secretion type I interferons (i.e. IFN-α/β), which induce transcription genes that cause to adopt an antiviral state. Many viruses have adapted mechanisms evade IFN-α/β-mediated responses. The leader protein mengovirus, a picornavirus, has been implicated as IFN-α/β antagonist. Here, we show inhibits both presence zinc finger motif in its N-terminus phosphorylation threonine-47 are required for this function. Transcription relies...
Stress granules (SG) are cytoplasmic aggregates of stalled translation preinitiation complexes that form in cells exposed to various environmental stresses. Here, we show stress assemble infected with Theiler's murine encephalomyelitis virus (TMEV) mutants carrying alterations the leader (L) protein, but not wild-type TMEV. also formed STAT1-deficient cells, suggesting SG formation was a consequence increased type I interferon (IFN) production when were mutant virus. Ectopic expression L...
Interferon beta (IFN-β) is a key component of cellular innate immunity in mammals, and it constitutes the first line defense during viral infection. Studies with cultured cells previously showed that almost all nucleated are able to produce IFN-β various extents, but information about vivo sources remains incomplete. By applying immunohistochemistry employing conditional-reporter mice express firefly luciferase under control promoter either or only distinct cell types, we found astrocytes...
Both endotherms and ectotherms (e.g., fish) increase their body temperature to limit pathogen infection. Ectotherms do so by moving warmer places, hence the term "behavioral fever." We studied manifestation of behavioral fever in common carp infected cyprinid herpesvirus 3, a native pathogen. Carp maintained at 24°C died from infection, whereas those housed multi-chamber tanks encompassing 24°C–32°C gradient migrated transiently warmest compartment survived as consequence. Behavioral...