174 research outputs found
Corrigendum: Analysis of tick-borne encephalitis virus-induced host responses in human cells of neuronal origin and interferon-mediated protection
No abstract available
Analysis of tick-borne encephalitis virus-induced host responses in human cells of neuronal origin and interferon-mediated protection
Tick-borne encephalitis virus (TBEV) is a member of the genus Flavivirus. It can cause serious infections in humans that may result in encephalitis/meningoencephalitis. Although several studies have described the involvement of specific genes in the host response to TBEV infection in the central nervous system (CNS), the overall network remains poorly characterized. Therefore, we investigated the response of DAOY cells (human medulloblastoma cells derived from cerebellar neurons) to TBEV (Neudoerfl strain, Western subtype) infection to characterize differentially expressed genes by transcriptome analysis. Our results revealed a wide panel of interferon-stimulated genes (ISGs) and pro-inflammatory cytokines, including type III but not type I (or II) interferons (IFNs), which are activated upon TBEV infection, as well as a number of non-coding RNAs, including long non-coding RNAs. To obtain a broader view of the pathways responsible for eliciting an antiviral state in DAOY cells we examined the effect of type I and III IFNs and found that only type I IFN pre-treatment inhibited TBEV production. The cellular response to TBEV showed only partial overlap with gene expression changes induced by IFN-β treatment – suggesting a virus-specific signature – and we identified a group of ISGs that were highly up-regulated following IFN-β treatment. Moreover, a high rate of down-regulation was observed for a wide panel of pro-inflammatory cytokines upon IFN-β treatment. These data can serve as the basis for further studies of host–TBEV interactions and the identification of ISGs and/or lncRNAs with potent antiviral effects in cases of TBEV infection in human neuronal cells
Genomic Resources Notes accepted 1 April 2014 - 31 May 2014
Genomic Resources Development Consortium.This article documents the public availability of a global transcriptome comparison between Lyme disease tick vectors, Ixodes scapularis and Ixodes ricinus.Peer Reviewe
Invasive potential of Borrelia burgdorferi sensu stricto ospC type L strains increases the possible disease risk to humans in the regions of their distribution
Hemelipoglycoprotein from the ornate sheep tick, dermacentor marginatus: structural and functional characterization
<p>Abstract</p> <p>Background</p> <p>Tick carrier proteins are able to bind, transport, and store host-blood heme, and thus they function also as antioxidants. Nevertheless, the role of carrier proteins in ticks is not fully understood. Some of them are found also in tick males which do not feed on hosts to such an extent such as females (there are differences in male feeding in different tick species) and thus they are not dealing with such an excess of heme; some of the carrier proteins were found in salivary glands where the processing of blood and thus release of heme does not occur. Besides, the carrier proteins bind relatively low amounts of heme (in one case only two molecules of heme per protein) compared to their sizes (above 200 kDa).</p> <p>The main aim of this study is the biochemical characterization of a carrier protein from the ornate sheep tick <it>Dermacentor marginatus</it>, hemelipoglycoprotein, with emphasis on its size in native conditions, its glycosylation and identification of its modifying glycans, and examining its carbohydrate-binding specificity.</p> <p>Results</p> <p>Hemelipoglycoprotein from <it>D. marginatus </it>plasma was purified in native state by immunoprecipitation and denatured using electroelution from SDS-PAGE separated plasma. The protein (290 kDa) contains two subunits with molecular weights 100 and 95 kDa. It is glycosylated by high-mannose and complex <it>N</it>-glycans HexNAc<sub>2</sub>Hex<sub>9</sub>, HexNAc<sub>2</sub>Hex<sub>10</sub>, HexNAc<sub>4</sub>Hex<sub>7</sub>, and HexNAc<sub>4</sub>Hex<sub>8</sub>. The purified protein is able to agglutinate red blood cells and has galactose- and mannose-binding specificity. The protein is recognized by antibodies directed against plasma proteins with hemagglutination activity and against fibrinogen-related lectin Dorin M from the tick <it>Ornithodoros moubata</it>.</p> <p>It forms high-molecular weight complexes with putative fibrinogen-related proteins and other unknown proteins under native conditions in tick plasma. Feeding does not increase its amounts in male plasma. The hemelipoglycoprotein was detected also in hemocytes, salivary glands, and gut. In salivary glands, the protein was present in both glycosylated and nonglycosylated forms.</p> <p>Conclusion</p> <p>A 290 kDa hemelipoglycoprotein from the tick <it>Dermacentor marginatus</it>, was characterized. The protein has two subunits with 95 and 100 kDa, and bears high-mannose and complex <it>N</it>-linked glycans. In hemolymph, it is present in complexes with putative fibrinogen-related proteins. This, together with its carbohydrate-binding activity, suggests its possible involvement in tick innate immunity. In fed female salivary glands, it was found also in a form corresponding to the deglycosylated protein.</p
Functional and Immunological Relevance of Anaplasma marginale Major Surface Protein 1a Sequence and Structural Analysis.
Bovine anaplasmosis is caused by cattle infection with the tick-borne bacterium, Anaplasma marginale. The major surface protein 1a (MSP1a) has been used as a genetic marker for identifying A. marginale strains based on N-terminal tandem repeats and a 5'-UTR microsatellite located in the msp1a gene. The MSP1a tandem repeats contain immune relevant elements and functional domains that bind to bovine erythrocytes and tick cells, thus providing information about the evolution of host-pathogen and vector-pathogen interactions. Here we propose one nomenclature for A. marginale strain classification based on MSP1a. All tandem repeats among A. marginale strains were classified and the amino acid variability/frequency in each position was determined. The sequence variation at immunodominant B cell epitopes was determined and the secondary (2D) structure of the tandem repeats was modeled. A total of 224 different strains of A. marginale were classified, showing 11 genotypes based on the 5'-UTR microsatellite and 193 different tandem repeats with high amino acid variability per position. Our results showed phylogenetic correlation between MSP1a sequence, secondary structure, B-cell epitope composition and tick transmissibility of A. marginale strains. The analysis of MSP1a sequences provides relevant information about the biology of A. marginale to design vaccines with a cross-protective capacity based on MSP1a B-cell epitopes
anti-tick vaccines to prevent tick-borne diseases in Europe
Ixodes ricinus transmits bacterial, protozoal and viral pathogens, causing
disease and forming an increasing health concern in Europe. ANTIDotE is an
European Commission funded consortium of seven institutes, which aims to
identify and characterize tick proteins involved in feeding and pathogen
transmission. The knowledge gained will be used to develop and evaluate anti-
tick vaccines that may prevent multiple human tick-borne diseases. Strategies
encompassing anti-tick vaccines to prevent transmission of pathogens to
humans, animals or wildlife will be developed with relevant stakeholders with
the ultimate aim of reducing the incidence of tick-borne diseases in humans
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