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- Ylipaasto, P., et al.
(författare)
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Enterovirus-induced gene expression profile is critical for human pancreatic islet destruction
- 2012
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Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 0012-186X .- 1432-0428. ; 55:12, s. 3273-3283
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Tidskriftsartikel (refereegranskat)abstract
- Aims/hypothesis Virally induced inflammatory responses, beta cell destruction and release of beta cell autoantigens may lead to autoimmune reactions culminating in type 1 diabetes. Therefore, viral capability to induce beta cell death and the nature of virus-induced immune responses are among key determinants of diabetogenic viruses. We hypothesised that enterovirus infection induces a specific gene expression pattern that results in islet destruction and that such a host response pattern is not shared among all enterovirus infections but varies between virus strains. Methods The changes in global gene expression and secreted cytokine profiles induced by lytic or benign enterovirus infections were studied in primary human pancreatic islet using DNA microarrays and viral strains either isolated at the clinical onset of type 1 diabetes or capable of causing a diabetes-like condition in mice. Results The expression of pro-inflammatory cytokine genes (IL-1-a, IL-1-β and TNF-a) that also mediate cytokineinduced beta cell dysfunction correlated with the lytic potential of a virus. Temporally increasing gene expression levels of double-stranded RNArecognition receptors, antiviral molecules, cytokines and chemokines were detected for all studied virus strains. Lytic coxsackievirus B5 (CBV-5)-DS infection also downregulated genes involved in glycolysis and insulin secretion. Conclusions/interpretation The results suggest a distinct, virusstrain- specific, gene expression pattern leading to pancreatic islet destruction and pro-inflammatory effects after enterovirus infection. However, neither viral replication nor cytotoxic cytokine production alone are sufficient to induce necrotic cell death. More likely the combined effect of these and possibly cellular energy depletion lie behind the enterovirus-induced necrosis of islets.
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| 2. |
- Saijets, Salla, et al.
(författare)
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Enterovirus infection and activation of human umbilical vein endothelial cells
- 2003
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Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 70:3, s. 430-439
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Tidskriftsartikel (refereegranskat)abstract
- Gastrointestinal tract associated lymphoid tissue is considered to be the main replication site for enteroviruses. In order to invade tissues to reach pancreatic islets, cardiac muscles, and other secondary replication sites, the virus has to survive circulation in the blood and find a way to get through endothelial cells. In the present study, the susceptibility of human endothelial cells to infections caused by human parechovirus 1 and several prototype strains of enteroviruses, representing different species (human poliovirus, human enterovirus B and C), and acting through different receptor families was examined. Primary endothelial cells isolated from human umbilical vein by collagenase perfusion and also an established human endothelial cell line, HUVEC, were used. Primary endothelial cells were highly susceptible to several serotypes of enteroviruses (coxsackievirus A13, echoviruses 6, 7, 11, 30, and poliovirus 1). However, coxsackievirus A 9 and echovirus 1 infected only a few individual cells while human parechovirus 1 and coxsackie B viruses did not show evidence of replication in primary endothelial cells. In general, primary endothelial cells were more sensitive to infection-induced cytolytic effect than HUVEC. Activation of endothelial cells by interleukin-1▀ did not change the pattern of enterovirus infection. Immunofluorescence stainings of infected primary endothelial cells showed that expression of activation markers, E-selectin, and intercellular adhesion molecule-1, was clearly increased by several virus infections and the former molecule also by exposing cells to UV-light inactivated coxsackieviruses. In contrast, human leukocyte antigen-DR expression was not increased by virus infection.
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| 3. |
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| 4. |
- Ylipaasto, P, et al.
(författare)
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Enterovirus infection in human pancreatic islet cells, islet tropism in vivo and receptor involvement in cultured islet beta cells.
- 2004
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Ingår i: Diabetologia. - Berlin : Springer verlag. - 0012-186X .- 1432-0428. ; 47:2, s. 225-239
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Tidskriftsartikel (refereegranskat)abstract
- AIMS/HYPOTHESIS: It is thought that enterovirus infections cause beta-cell damage and contribute to the development of Type 1 diabetes by replicating in the pancreatic islets. We sought evidence for this through autopsy studies and by investigating known enterovirus receptors in cultured human islets. METHODS: Autopsy pancreases from 12 newborn infants who died of fulminant coxsackievirus infections and from 65 Type 1 diabetic patients were studied for presence of enteroviral ribonucleic acid by in situ hybridisation. Forty non-diabetic control pancreases were included in the study. The expression and role of receptor candidates in cultured human islets were investigated with receptor-specific antibodies using immunocytochemistry and functional assays. RESULTS: Enterovirus-positive islet cells were found in some of both autopsy specimen collections, but not in control pancreases. No infected cells were seen in exocrine tissue. The cell surface molecules, poliovirus receptor and integrin alphavbeta3, which act as enterovirus receptors in established cell lines, were expressed in beta cells. Antibodies to poliovirus receptor, human coxsackievirus and adenovirus receptor and integrin alphavbeta3 protected islets and beta cells from adverse effects of poliovirus, coxsackie B viruses, and several of the arginine-glycine-aspartic acid motifs containing enteroviruses and human parechovirus 1 respectively. No evidence was found for expression of the decay-accelerating factor which acts as a receptor for several islet-cell-replicating echoviruses in established cell lines. CONCLUSIONS/INTERPRETATION: The results show a definite islet-cell tropism of enteroviruses in the human pancreas. Some enteroviruses seem to use previously identified cell surface molecules as receptors in beta cells, whereas the identity of receptors used by other enteroviruses remains unknown.
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