| 1. |
- Nilsson, Emma C, et al.
(författare)
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Sialic acid is a cellular receptor for coxsackievirus A24 variant, an emerging virus with pandemic potential
- 2008
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Ingår i: Journal of Virology. - Baltimore : American Society for Microbiology. - 0022-538X .- 1098-5514. ; 82:6, s. 3061-3068
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Tidskriftsartikel (refereegranskat)abstract
- Binding to target cell receptors is a critical step in the virus life cycle. Coxsackievirus A24 variant (CVA24v) has pandemic potential and is a major cause of acute hemorrhagic conjunctivitis, but its cellular receptor has hitherto been unknown. Here we show that CVA24v fails to bind to and infect CHO cells defective in sialic acid expression. Binding of CVA24v to and infection of corneal epithelial cells are efficiently inhibited by treating cells with a sialic acid-cleaving enzyme or sialic acid-binding lectins and by treatment of the virus with soluble, multivalent sialic acid. Protease treatment of cells efficiently inhibited virus binding, suggesting that the receptor is a sialylated glycoprotein. Like enterovirus type 70 and influenza A virus, CVA24v can cause pandemics. Remarkably, all three viruses use the same receptor. Since several unrelated viruses with tropism for the eye use this receptor, sialic acid-based antiviral drugs that prevent virus entry may be useful for topical treatment of such infections.
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| 2. |
- Anagandula, Mahesh, et al.
(författare)
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Infection of Human Islets of Langerhans With Two Strains of Coxsackie B Virus Serotype 1 : Assessment of Virus Replication, Degree of Cell Death and Induction of Genes Involved in the Innate Immunity Pathway
- 2014
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Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 86:8, s. 1402-1411
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Tidskriftsartikel (refereegranskat)abstract
- Type 1 diabetes mellitus is believed to be triggered, in part, by one or more environmental factors and human enteroviruses (HEVs) are among the candidates. Therefore, this study has examined whether two strains of HEV may differentially affect the induction of genes involved in pathways leading to the synthesis of islet hormones, chemokines and cytokines in isolated, highly purified, human islets. Isolated, purified human pancreatic islets were infected with strains of Coxsackievirus B1. Viral replication and the degree of CPE/islet dissociation were monitored. The expression of insulin, glucagon, CXCL10, TLR3, IF1H1, CCL5, OAS-1, IFN beta, and DDX58 was analyzed. Both strains replicated in islets but only one of strain caused rapid islet dissociation/CPE. Expression of the insulin gene was reduced during infection of islets with either viral strain but the gene encoding glucagon was unaffected. All genes analyzed which are involved in viral sensing and the development of innate immunity were induced by Coxsackie B viruses, with the notable exception of TLR3. There was no qualitative difference in the expression pattern between each strain but the magnitude of the response varied between donors. The lack of virus induced expression of TLR3, together with the differential regulation of IF1H1, OAS1 and IFN beta, (each of which has polymorphic variants influence the predisposition to type 1 diabetes), that might result in defective clearance of virus from islet cells. The reduced expression of the insulin gene and the unaffected expression of the gene encoding glucagon by Coxsackie B1 infection is consistent with the preferential beta-cell tropism of the virus.
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| 3. |
- Hamalainen, Sanna, et al.
(författare)
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Coxsackievirus B1 Reveals Strain Specific Differences in Plasmacytoid Dendritic Cell Mediated Immunogenicity
- 2014
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Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 86:8, s. 1412-1420
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Tidskriftsartikel (refereegranskat)abstract
- Enterovirus infections are usually mild but can also cause severe illnesses and play a role in chronic diseases, such as cardiomyopathies and type 1 diabetes. Host response to the invading virus can markedly modulate the course of the infection, and this response varies between individuals due to the polymorphism of immune response genes. However, it is currently not known if virus strains also differ in their ability to stimulate the host immune system. Coxsackievirus B1 (CBV1) causes severe epidemics in young infants and it has recently been connected with type 1 diabetes in seroepidemiological studies. This study evaluated the ability of different field isolates of CBV1 to induce innate immune responses in PBMCs. CBV1 strains differed markedly in their capacity to induce innate immune responses. Out of the 18 tested CBV1 strains two induced exceptionally strong alpha interferon (IFN-alpha) response in PBMC cultures. The responding cell type was found to be the plasmacytoid dendritic cell. Such a strong innate immune response was accompanied by an up-regulation of several other immune response genes and secretion of cytokines, which modulate inflammation, and adaptive immune responses. These results suggest that enterovirus-induced immune activation depends on the virus strain. It is possible that the immunotype of the virus modulates the course of the infection and plays a role in the pathogenesis of chronic immune-mediated enterovirus diseases.
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| 4. |
- Mistry, Nitesh, et al.
(författare)
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Coxsackievirus A24 variant uses aialic acid-containing O-Linked glycoconjugates as cellular receptors on human ocular cells
- 2011
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Ingår i: Journal of Virology. - Baltimore : American Society for Microbiology. - 0022-538X .- 1098-5514. ; 85:21, s. 11283-11290
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Tidskriftsartikel (refereegranskat)abstract
- Coxsackievirus A24 variant (CVA24v) is a main causative agent of acute hemorrhagic conjunctivitis (AHC), which is a highly contagious eye infection. Previously it has been suggested that CVA24v uses sialic acid-containing glycoconjugates as attachment receptors on corneal cells, but the nature of these receptors is poorly described. Here, we set out to characterize and identify the cellular components serving as receptors for CVA24v. Binding and infection experiments using corneal cells treated with deglycosylating enzymes or metabolic inhibitors of de novo glycosylation suggested that the receptor(s) used by CVA24v are constituted by sialylated O-linked glycans that are linked to one or more cell surface proteins but not to lipids. CVA24v bound better to mouse L929 cells overexpressing human P-selectin glycoprotein ligand-1 (PSGL-1) than to mock-transfected cells, suggesting that PSGL-1 is a candidate receptor for CVA24v. Finally, binding competition experiments using a library of mono- and oligosaccharides mimicking known PSGL-1 glycans suggested that CVA24v binds to Neu5Ac alpha 2,3Gal disaccharides (Neu5Ac is N-acetylneuraminic acid). These results provide further insights into the early steps of the CVA24v life cycle.
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| 5. |
- Nix, W Allan, et al.
(författare)
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Detection of all known parechoviruses by real-time PCR.
- 2008
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Ingår i: Journal of clinical microbiology. - 1098-660X. ; 46:8, s. 2519-24
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Tidskriftsartikel (refereegranskat)abstract
- The Parechovirus genus of the Picornaviridae family contains two species, Human parechovirus (HPeV) and Ljungan 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 genus Parechovirus. 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.
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