BACKGROUND: Tick-borne encephalitis (TBE) is a severe neuropathological disorder caused by tick-borne encephalitis virus (TBEV). Brain TBEV infection is characterized by extensive pathological neuroinflammation. The mechanism by which TBEV causes CNS destruction remains unclear, but growing evidence suggests that it involves both direct neuronal damage by the virus infection and indirect damage caused by the immune response. Here, we aimed to examine the TBEV-infection-induced innate immune response in mice and in human neural cells. We also compared cytokine/chemokine communication between naïve and infected neuronal cells and astrocytes. METHODS: We used a multiplexed Luminex system to measure multiple cytokines/chemokines and growth factors in mouse serum samples and brain tissue, and in human neuroblastoma cells (SK-N-SH) and primary cortical astrocytes (HBCA), which were infected with the highly pathogenic TBEV strain Hypr. We also investigated changes in cytokine/chemokine production in naïve HBCA cells treated with virus-free supernatants from TBEV-infected SK-N-SH cells and in naïve SK-N-SH cells treated with virus-free supernatants from TBEV-infected HBCA cells. Additionally, a plaque assay was performed to assess how cytokine/chemokine treatment influenced viral growth following TBEV infection. RESULTS: TBEV-infected mice exhibited time-dependent increases in serum and brain tissue concentrations of multiple cytokines/chemokines (mainly CXCL10/IP-10, and also CXCL1, G-CSF, IL-6, and others). TBEV-infected SK-N-SH cells exhibited increased production of IL-8 and RANTES and downregulated MCP-1 and HGF. TBEV infection of HBCA cells activated production of a broad spectrum of pro-inflammatory cytokines, chemokines, and growth factors (mainly IL-6, IL-8, CXCL10, RANTES, and G-CSF) and downregulated the expression of VEGF. Treatment of SK-N-SH with supernatants from infected HBCA induced expression of a variety of chemokines and pro-inflammatory cytokines, reduced SK-N-SH mortality after TBEV infection, and decreased virus growth in these cells. Treatment of HBCA with supernatants from infected SK-N-SH had little effect on cytokine/chemokine/growth factor expression but reduced TBEV growth in these cells after infection. CONCLUSIONS: Our results indicated that both neurons and astrocytes are potential sources of pro-inflammatory cytokines in TBEV-infected brain tissue. Infected/activated astrocytes produce cytokines/chemokines that stimulate the innate neuronal immune response, limiting virus replication, and increasing survival of infected neurons.

• MeSH
• cytokiny imunologie   metabolismus   MeSH
• klíšťová encefalitida imunologie   metabolismus   MeSH
• lidé MeSH
• mozek imunologie   metabolismus   patologie   MeSH
• myši MeSH
• neurony imunologie   metabolismus   virologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Equine herpesvirus 1 (EHV-1), like other members of the Alphaherpesvirinae subfamily, is a neurotropic virus causing latent infections in the nervous system of the natural host. In the present study, we have investigated EHV-1 replication (wild-type Jan-E strain and Rac-H laboratory strain) during long-term infection and during the passages of the virus in cultured neurons. The studies were performed on primary murine neurons, which are an excellent in vitro model for studying neurotropism and neurovirulence of EHV-1. Using real-time cell growth analysis, we have demonstrated for the first time that primary murine neurons are able to survive long-term EHV-1 infection. Positive results of real-time PCR test indicated a high level of virus DNA in cultured neurons, and during long-term infection, these neurons were still able to transmit the virus to the other cells. We also compared the neurovirulence of Rac-H and Jan-E EHV-1 strains after multiple passages of these strains in neuron cell culture. The results showed that multiple passages of EHV-1 in neurons lead to the inhibition of viral replication as early as in the third passage. Interestingly, the inhibition of the EHV-1 replication occurred exclusively in neurons, because the equine dermal (ED) cells co-cultivated with neuroculture medium from the third passage showed the presence of large amount of viral DNA. In conclusion, our results showed that certain balance between EHV-1 and neurons has been established during in vitro infection allowing neurons to survive long-term infection.

• MeSH
• herpesvirus 1 koní genetika   růst a vývoj   patogenita   fyziologie   MeSH
• herpetické infekce veterinární   virologie   MeSH
• hostitelská specificita MeSH
• koně MeSH
• kultivované buňky MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• nemoci koní virologie   MeSH
• neurony virologie   MeSH
• replikace viru MeSH
• sériové pasážování MeSH
• virulence MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Tick-borne encephalitis virus (TBEV) causes 13,000 cases of human meningitis and encephalitis annually. However, the structure of the TBEV virion and its interactions with antibodies are unknown. Here, we present cryo-EM structures of the native TBEV virion and its complex with Fab fragments of neutralizing antibody 19/1786. Flavivirus genome delivery depends on membrane fusion that is triggered at low pH. The virion structure indicates that the repulsive interactions of histidine side chains, which become protonated at low pH, may contribute to the disruption of heterotetramers of the TBEV envelope and membrane proteins and induce detachment of the envelope protein ectodomains from the virus membrane. The Fab fragments bind to 120 out of the 180 envelope glycoproteins of the TBEV virion. Unlike most of the previously studied flavivirus-neutralizing antibodies, the Fab fragments do not lock the E-proteins in the native-like arrangement, but interfere with the process of virus-induced membrane fusion.

• MeSH
• elektronová kryomikroskopie MeSH
• exprese genu MeSH
• fúze membrán genetika   MeSH
• imunoglobuliny - Fab fragmenty biosyntéza   chemie   MeSH
• internalizace viru MeSH
• koncentrace vodíkových iontů MeSH
• lidé MeSH
• multimerizace proteinu MeSH
• nádorové buněčné linie MeSH
• neurony patologie   virologie   MeSH
• neutralizující protilátky biosyntéza   chemie   MeSH
• proteinové domény MeSH
• protilátky virové biosyntéza   chemie   MeSH
• virion genetika   metabolismus   ultrastruktura   MeSH
• virové proteiny chemie   genetika   metabolismus   MeSH
• viry klíšťové encefalitidy genetika   metabolismus   ultrastruktura   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

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.

• MeSH
• aktivace transkripce MeSH
• cytokiny genetika   imunologie   MeSH
• interakce hostitele a patogenu MeSH
• interferony genetika   imunologie   MeSH
• klíšťová encefalitida genetika   imunologie   virologie   MeSH
• lidé MeSH
• neurony imunologie   virologie   MeSH
• viry klíšťové encefalitidy genetika   fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Tick-borne encephalitis virus (TBEV) causes serious, potentially fatal neurological infections that affect humans in endemic regions of Europe and Asia. Neurons are the primary target for TBEV infection in the central nervous system. However, knowledge about this viral infection and virus-induced neuronal injury is fragmental. Here, we directly examined the pathology that occurs after TBEV infection in human primary neurons. We exploited the advantages of advanced high-pressure freezing and freeze-substitution techniques to achieve optimal preservation of infected cell architecture. Electron tomographic (ET) reconstructions elucidated high-resolution 3D images of the proliferating endoplasmic reticulum, and individual tubule-like structures of different diameters in the endoplasmic reticulum cisternae of single cells. ET revealed direct connections between the tubule-like structures and viral particles in the endoplasmic reticulum. Furthermore, ET showed connections between cellular microtubules and vacuoles that harbored the TBEV virions in neuronal extensions. This study was the first to characterize the 3D topographical organization of membranous whorls and autophagic vacuoles in TBEV-infected human neurons. The functional importance of autophagy during TBEV replication was studied in human neuroblastoma cells; stimulation of autophagy resulted in significantly increased dose-dependent TBEV production, whereas the inhibition of autophagy showed a profound, dose-dependent decrease of the yield of infectious virus.

• MeSH
• autofagie účinky léků   genetika   MeSH
• benzylaminy farmakologie   MeSH
• chinazoliny farmakologie   MeSH
• endoplazmatické retikulum účinky léků   ultrastruktura   virologie   MeSH
• lidé MeSH
• mikrotubuly účinky léků   ultrastruktura   virologie   MeSH
• nádorové buněčné linie MeSH
• neurony účinky léků   ultrastruktura   virologie   MeSH
• nokodazol farmakologie   MeSH
• primární buněčná kultura MeSH
• replikace viru účinky léků   MeSH
• sirolimus farmakologie   MeSH
• tomografie elektronová MeSH
• virion účinky léků   růst a vývoj   ultrastruktura   MeSH
• viry klíšťové encefalitidy účinky léků   růst a vývoj   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Paraneoplastická limbická encefalitida je vzácné onemocnění náležící do skupiny paraneoplastických neurologických syndromů. V diagnostice hraje zásadní roli zobrazení mozku magnetickou rezonancí. Předkládáme kazuistiku 57letého muže, u něhož vyšetření magnetickou rezonancí jistě přispělo ke stanovení této diagnózy. Další významnou součástí diagnostického postupu je průkaz specifických, takzvaných antineuronálních autoprotilátek Prognóza choroby nebývá dobrá, je závislá především na možnostech suprese základního tumorózního onemocnění.

Paraneoplastic limbic encephalitis is a rare disorder which belongs to a group of paraneoplastic neurologic syndromes. The diagnostic role of magnetic resonance imaging (MRI) is of utmost importance. We report a case of a 57-year-old man in whom MRI significantly contributed to establishing of proper diagnosis. Other important diagnostic test includes identification of specific, so called antineural auto antibodies. Typically, the prognosis of the disease is not good; it depends mainly on the ability to control the underlying malignant disease.

• Klíčová slova
• magnetická rezonance,
• MeSH
• autoprotilátky izolace a purifikace   MeSH
• diferenciální diagnóza MeSH
• elektroencefalografie metody   využití   MeSH
• klinické laboratorní techniky využití   MeSH
• lidé středního věku MeSH
• lidé MeSH
• limbická encefalitida diagnóza   MeSH
• magnetická rezonanční tomografie metody   využití   MeSH
• nádory centrálního nervového systému diagnóza   komplikace   sekundární   MeSH
• neurony chemie   metabolismus   virologie   MeSH
• paraneoplastické neurologické syndromy diagnóza   MeSH
• paraneoplastické syndromy MeSH
• poruchy paměti diagnóza   etiologie   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

Tick-borne encephalitis (TBE) is one of the leading and most dangerous human viral neuroinfections in Europe and north-eastern Asia. The clinical manifestations include asymptomatic infections, fevers and debilitating encephalitis that might progress into chronic disease or fatal infection. To understand TBE pathology further in host nervous systems, three human neural cell lines, neuroblastoma, medulloblastoma and glioblastoma, were infected with TBE virus (TBEV). The susceptibility and virus-mediated cytopathic effect, including ultrastructural and apoptotic changes of the cells, were examined. All the neural cell lines tested were susceptible to TBEV infection. Interestingly, the neural cells produced about 100- to 10,000-fold higher virus titres than the conventional cell lines of extraneural origin, indicating the highly susceptible nature of neural cells to TBEV infection. The infection of medulloblastoma and glioblastoma cells was associated with a number of major morphological changes, including proliferation of membranes of the rough endoplasmic reticulum and extensive rearrangement of cytoskeletal structures. The TBEV-infected cells exhibited either necrotic or apoptotic morphological features. We observed ultrastructural apoptotic signs (condensation, margination and fragmentation of chromatin) and other alterations, such as vacuolation of the cytoplasm, dilatation of the endoplasmic reticulum cisternae and shrinkage of cells, accompanied by a high density of the cytoplasm. On the other hand, infected neuroblastoma cells did not exhibit proliferation of membranous structures. The virions were present in both the endoplasmic reticulum and the cytoplasm. Cells were dying preferentially by necrotic mechanisms rather than apoptosis. The neuropathological significance of these observations is discussed.

• MeSH
• apoptóza MeSH
• buněčná membrána ultrastruktura   MeSH
• buněčná smrt MeSH
• buněčné linie MeSH
• cytoplazma virologie   MeSH
• cytoskelet metabolismus   ultrastruktura   MeSH
• endoplazmatické retikulum virologie   MeSH
• lidé MeSH
• neuroglie ultrastruktura   virologie   MeSH
• neurony ultrastruktura   virologie   MeSH
• virion ultrastruktura   MeSH
• viry klíšťové encefalitidy fyziologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH

• MeSH
• herpes simplex virologie   MeSH
• latence viru MeSH
• lidé MeSH
• lidský herpesvirus 1 genetika   metabolismus   MeSH
• neurony virologie   MeSH
• proteinkinasy fyziologie   MeSH
• virové proteiny genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH