BACKGROUND: Tick-borne encephalitis (TBE) is the most common tick-borne viral infection in Eurasia. Outcomes range from asymptomatic infection to fatal encephalitis, with host genetics likely playing a role. BALB/c mice have intermediate susceptibility to TBE virus (TBEV) and STS mice are highly resistant, whereas the recombinant congenic strain CcS-11, which carries 12.5% of the STS genome on the BALB/c background, is more susceptible than BALB/c mice. In the present study, we employed these genetically distinct mouse models to investigate the host response to TBEV infection in both peripheral macrophages, one of the initial target cell populations, and the brain, the terminal target organ of the virus. METHODS: TBEV growth and the production of key cytokines and chemokines were measured and compared in macrophages derived from BALB/c, CcS-11, and STS mice. In addition, brains from these TBEV-infected mouse strains underwent in-depth transcriptomic analysis. RESULTS: Virus production in BALB/c and CcS-11 macrophages exhibited similar kinetics 24 and 48 h post-infection (hpi), but CcS-11 macrophages yielded significantly higher titers 72 hpi. Macrophages from both sensitive strains demonstrated elevated chemokine and proinflammatory cytokine production upon infection, whereas the resistant strain, STS, showed no cytokine/chemokine activation. Transcriptomic analysis of brain tissue demonstrated that the genetic background of the mouse strains dictated their transcriptional response to infection. The resistant strain exhibited a more robust cell-mediated immune response, whereas both sensitive strains showed a less effective cell-mediated response but increased cytokine signaling and signs of demyelination, with loss of oligodendrocytes. CONCLUSIONS: Our findings suggest that variations in susceptibility linked to host genetic background correspond with distinct host responses, both in the periphery upon virus entry into the organism and in the brain, the target organ of the virus. These results provide insights into the influence of host genetics on the clinical trajectory of TBE.

• Klíčová slova
• Genetics, Macrophages, Mouse model, Neuroinflammation, Tick-borne encephalitis, Tick-borne encephalitis virus, Transcriptomics,
• MeSH
• cytokiny * metabolismus   genetika   MeSH
• genotyp MeSH
• klíšťová encefalitida * imunologie   virologie   genetika   MeSH
• makrofágy * imunologie   virologie   MeSH
• mozek * virologie   imunologie   MeSH
• myši inbrední BALB C * MeSH
• myši MeSH
• viry klíšťové encefalitidy * genetika   fyziologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• cytokiny * MeSH

Enveloped viruses, such as flaviviruses and coronaviruses, are pathogens of significant medical concern that cause severe infections in humans. Some photosensitizers are known to possess virucidal activity against enveloped viruses, targeting their lipid bilayer. Here we report a series of halogenated difluoroboron-dipyrromethene (BODIPYs) photosensitizers with strong virus-inactivating activity. Our structure-activity relationship analysis revealed that BODIPY scaffolds with a heavy halogen atom demonstrate significant efficacy against both tick-borne encephalitis virus (TBEV; Flaviviridae family) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; Coronaviridae family) along with high singlet oxygen quantum yields. Moreover, select compounds also inactivated other enveloped viruses, such as herpes simplex virus type 1 and monkeypox virus. The nature and length of the alkyl side chain notably influenced the virus-inactivating activity of BODIPY molecules. Furthermore, molecular dynamics studies highlighted the critical importance of the positioning of the chromophore moiety within the lipid bilayer. As membrane-targeting photosensitizers, BODIPYs interact directly with virus particles, causing damage to the viral envelope membranes. Thus, TBEV pretreated with BODIPY was completely noninfective for lab mice. Consequently, BODIPY-based photosensitizers hold potential either as broad-spectrum virus-inactivating antivirals against a variety of phylogenetically unrelated enveloped viruses or as potent inactivators of viruses for the development of vaccines for preventing life-threatening emerging viral diseases.

• Klíčová slova
• BODIPY, enveloped viruses, membrane-targeting photosensitizer, singlet oxygen photogeneration, virus-inactivating activity,
• MeSH
• antivirové látky * farmakologie   chemie   MeSH
• Cercopithecus aethiops MeSH
• fotosenzibilizující látky * chemie   farmakologie   účinky záření   MeSH
• halogenace MeSH
• lidé MeSH
• myši MeSH
• porfobilinogen analogy a deriváty   chemie   farmakologie   MeSH
• SARS-CoV-2 účinky léků   MeSH
• singletový kyslík * metabolismus   chemie   MeSH
• sloučeniny boru * chemie   farmakologie   MeSH
• Vero buňky MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene MeSH Prohlížeč
• antivirové látky * MeSH
• dipyrromethene MeSH Prohlížeč
• fotosenzibilizující látky * MeSH
• porfobilinogen MeSH
• singletový kyslík * MeSH
• sloučeniny boru * MeSH

Tick-borne infections are the most common vector-borne diseases in the USA. Ticks harbor and transmit several infections with Lyme disease being the most common tickborne infection in the US and Europe. Lack of awareness about tick populations, specific diagnostic tests, and overlapping signs and symptoms of tick-borne infections can often lead to misdiagnosis affecting treatment and the prevalence data reported especially for non-Lyme tick-borne infections. The diagnostic tests currently available for tick-borne diseases are severely limited in their ability to provide accurate results and cannot detect multiple pathogens in a single run. The multiplex protein microarray developed at Vibrant was designed to detect multiple serological antibodies thereby detecting exposure to multiple pathogens simultaneously. Our microarray in its present form can accommodate 400 antigens (molecules that can bind to specific antibodies) and can multiplex across antigen types, whole cell lysates, recombinant proteins, and peptides. A designed array containing multiple antigens of several microbes including Borrelia burgdorferi, the Lyme disease spirochete, was manufactured and evaluated. The immunoglobulin M (IgM) and G (IgG) responses against several tick-borne microbes and other infectious agents were analyzed for analytical and clinical performance. The microarray improved IgM and IgG sensitivities and specificities of individual microbes when compared with the respective gold standards. The testing was also performed in a single run in comparison to multiple runs needed for comparable testing standards. In summary, our study presents a flexible multiplex microarray platform that can provide quick results with high sensitivity and specificity for evaluating exposure to varied infectious agents especially tick-borne pathogens.

• Klíčová slova
• Co-infections, Immunoglobulin, Infectious disease, Lyme disease, Microarray, Multiplex, Tick bite, Tick-borne infections,
• MeSH
• antigeny bakteriální imunologie   MeSH
• Borrelia burgdorferi * imunologie   MeSH
• čipová analýza proteinů * metody   MeSH
• imunoglobulin G imunologie   krev   MeSH
• imunoglobulin M krev   imunologie   MeSH
• klíšťata mikrobiologie   MeSH
• lidé MeSH
• lymeská nemoc diagnóza   imunologie   MeSH
• nemoci přenášené klíšťaty * diagnóza   imunologie   MeSH
• protilátky bakteriální * imunologie   krev   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antigeny bakteriální MeSH
• imunoglobulin G MeSH
• imunoglobulin M MeSH
• protilátky bakteriální * MeSH

In RNA interference (RNAi), long double-stranded RNA is cleaved by the Dicer endonuclease into small interfering RNAs (siRNAs), which guide degradation of complementary RNAs. While RNAi mediates antiviral innate immunity in plants and many invertebrates, vertebrates have adopted a sequence-independent response and their Dicer produces siRNAs inefficiently because it is adapted to process small hairpin microRNA precursors in the gene-regulating microRNA pathway. Mammalian endogenous RNAi is thus a rudimentary pathway of unclear significance. To investigate its antiviral potential, we modified the mouse Dicer locus to express a truncated variant (DicerΔHEL1) known to stimulate RNAi and we analyzed how DicerΔHEL1/wt mice respond to four RNA viruses: coxsackievirus B3 and encephalomyocarditis virus from Picornaviridae; tick-borne encephalitis virus from Flaviviridae; and lymphocytic choriomeningitis virus (LCMV) from Arenaviridae. Increased Dicer activity in DicerΔHEL1/wt mice did not elicit any antiviral effect, supporting an insignificant antiviral function of endogenous mammalian RNAi in vivo. However, we also observed that sufficiently high expression of DicerΔHEL1 suppressed LCMV in embryonic stem cells and in a transgenic mouse model. Altogether, mice with increased Dicer activity offer a new benchmark for identifying and studying viruses susceptible to mammalian RNAi in vivo.

In RNA interference (RNAi), the enzyme Dicer cuts long double-stranded RNA into small interfering RNAs that degrade matching RNAs. RNAi is a key antiviral defense in plants and invertebrates but vertebrates evolved a principally different antiviral defense. The authors genetically modified Dicer in mice to activate RNAi in mammals. These modified mice were tested against four RNA viruses but showed no significant antiviral response. However, further increased expression of modified Dicer did suppress one virus (lymphocytic choriomeningitis virus) in embryonic stem cells and in a transgenic mouse model, suggesting that some viruses might be sensitive to increased RNAi activity in mammals.

• MeSH
• DEAD-box RNA-helikasy genetika   metabolismus   MeSH
• malá interferující RNA genetika   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• přirozená imunita * genetika   MeSH
• ribonukleasa III * genetika   metabolismus   MeSH
• RNA interference * MeSH
• virus encefalomyokarditidy genetika   imunologie   MeSH
• virus lymfocytární choriomeningitidy imunologie   genetika   MeSH
• viry klíšťové encefalitidy genetika   imunologie   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• DEAD-box RNA-helikasy MeSH
• Dicer1 protein, mouse MeSH Prohlížeč
• malá interferující RNA MeSH
• ribonukleasa III * MeSH

Tick-borne encephalitis (TBE) virus (TBEV) is transmitted to humans via tick bites. Infection is benign in >90% of the cases but can cause mild (<5%), moderate (<4%), or severe (<1%) encephalitis. We show here that ∼10% of patients hospitalized for severe TBE in cohorts from Austria, Czech Republic, and France carry auto-Abs neutralizing IFN-α2, -β, and/or -ω at the onset of disease, contrasting with only ∼1% of patients with moderate and mild TBE. These auto-Abs were found in two of eight patients who died and none of 13 with silent infection. The odds ratios (OR) for severe TBE in individuals with these auto-Abs relative to those without them in the general population were 4.9 (95% CI: 1.5-15.9, P < 0.0001) for the neutralization of only 100 pg/ml IFN-α2 and/or -ω, and 20.8 (95% CI: 4.5-97.4, P < 0.0001) for the neutralization of 10 ng/ml IFN-α2 and -ω. Auto-Abs neutralizing type I IFNs accounted for ∼10% of severe TBE cases in these three European cohorts.

• MeSH
• autoprotilátky * imunologie   MeSH
• dospělí MeSH
• interferon typ I * imunologie   MeSH
• klíšťová encefalitida * imunologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• neutralizující protilátky * imunologie   MeSH
• senioři MeSH
• viry klíšťové encefalitidy imunologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH
• Rakousko epidemiologie   MeSH
• Názvy látek
• autoprotilátky * MeSH
• interferon typ I * MeSH
• neutralizující protilátky * MeSH

In this study, we employed short- and long-read sequencing technologies to delineate the transcriptional architecture of the human monkeypox virus and to identify key regulatory elements that govern its gene expression. Specifically, we conducted a transcriptomic analysis to annotate the transcription start sites (TSSs) and transcription end sites (TESs) of the virus by utilizing Cap Analysis of gene expression sequencing on the Illumina platform and direct RNA sequencing on the Oxford Nanopore technology device. Our investigations uncovered significant complexity in the use of alternative TSSs and TESs in viral genes. In this research, we also detected the promoter elements and poly(A) signals associated with the viral genes. Additionally, we identified novel genes in both the left and right variable regions of the viral genome.IMPORTANCEGenerally, gaining insight into how the transcription of a virus is regulated offers insights into the key mechanisms that control its life cycle. The recent outbreak of the human monkeypox virus has underscored the necessity of understanding the basic biology of its causative agent. Our results are pivotal for constructing a comprehensive transcriptomic atlas of the human monkeypox virus, providing valuable resources for future studies.

• Klíčová slova
• CAGE-Seq, long-read sequencing, monkeypox virus, nanopore sequencing, poxvirus, transcriptome,
• MeSH
• genom virový MeSH
• lidé MeSH
• počátek transkripce * MeSH
• promotorové oblasti (genetika) MeSH
• RNA virová genetika   MeSH
• sekvenční analýza RNA * metody   MeSH
• stanovení celkové genové exprese MeSH
• transkriptom * MeSH
• virus opičích neštovic genetika   MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• RNA virová MeSH

Ultraviolet-C (UV-C) radiation and ozone gas are potential mechanisms employed to inactivate the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), each exhibiting distinct molecular-level modalities of action. To elucidate these disparities and deepen our understanding, we delve into the intricacies of SARS-CoV-2 inactivation via UV-C and ozone gas treatments, exploring their distinct molecular-level impacts utilizing a suite of advanced techniques, including biological atomic force microscopy (Bio-AFM) and single virus force spectroscopy (SVFS). Whereas UV-C exhibited no perceivable alterations in virus size or surface topography, ozone gas treatment elucidated pronounced changes in both parameters, intensifying with prolonged exposure. Furthermore, a nuanced difference was observed in virus-host cell binding post-treatment: ozone gas distinctly reduced SARS-CoV-2 binding to host cells, while UV-C maintained the status quo. The results derived from these methodical explorations underscore the pivotal role of advanced Bio-AFM techniques and SVFS in enhancing our understanding of virus inactivation mechanisms, offering invaluable insights for future research and applications in viral contamination mitigation.

• Klíčová slova
• binding activity, infectivity test, sterilization mechanisms, structural characteristics, topographical characteristics,
• MeSH
• Cercopithecus aethiops MeSH
• COVID-19 * MeSH
• inaktivace viru * účinky léků   účinky záření   MeSH
• lidé MeSH
• mikroskopie atomárních sil * MeSH
• ozon * chemie   farmakologie   MeSH
• plazmové plyny chemie   farmakologie   MeSH
• SARS-CoV-2 * účinky léků   MeSH
• sterilizace metody   MeSH
• ultrafialové záření * MeSH
• Vero buňky MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ozon * MeSH
• plazmové plyny MeSH

Tick-borne encephalitis virus (TBEV) is a tick-borne flavivirus that induces severe central nervous system disorders. It has recently raised concerns due to an expanding geographical range and increasing infection rates. Existing vaccines, though effective, face low coverage rates in numerous TBEV endemic regions. Our previous work demonstrated the immunogenicity and full protection afforded by a TBEV vaccine based on virus-like particles (VLPs) produced in Leishmania tarentolae cells in immunization studies in a mouse model. In the present study, we explored the impact of adjuvants (AddaS03™, Alhydrogel®+MPLA) and administration routes (subcutaneous, intramuscular) on the immune response. Adjuvanted groups exhibited significantly enhanced antibody responses, higher avidity, and more balanced Th1/Th2 response. IFN-γ responses depended on the adjuvant type, while antibody levels were influenced by both adjuvant and administration routes. The combination of Leishmania-derived TBEV VLPs with Alhydrogel® and MPLA via intramuscular administration emerged as a highly promising prophylactic vaccine candidate, eliciting a robust, balanced immune response with substantial neutralization potential.

• Klíčová slova
• Adjuvants, Leishmania tarentolae, Tick-borne encephalitis virus, Vaccine, Virus-like particles,
• MeSH
• adjuvancia imunologická * aplikace a dávkování   MeSH
• adjuvantní vakcína aplikace a dávkování   MeSH
• imunogenicita vakcíny MeSH
• injekce intramuskulární MeSH
• interferon gama imunologie   MeSH
• klíšťová encefalitida * prevence a kontrola   imunologie   MeSH
• Leishmania * imunologie   MeSH
• myši inbrední BALB C MeSH
• myši MeSH
• neutralizující protilátky krev   imunologie   MeSH
• protilátky virové * krev   imunologie   MeSH
• syntetické vakcíny * imunologie   aplikace a dávkování   MeSH
• Th1 buňky imunologie   MeSH
• virové vakcíny * imunologie   aplikace a dávkování   MeSH
• viry klíšťové encefalitidy * imunologie   MeSH
• VLP vakcíny * imunologie   aplikace a dávkování   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adjuvancia imunologická * MeSH
• adjuvantní vakcína MeSH
• interferon gama MeSH
• neutralizující protilátky MeSH
• protilátky virové * MeSH
• syntetické vakcíny * MeSH
• virové vakcíny * MeSH
• VLP vakcíny * MeSH

Tick-borne encephalitis virus (TBEV) targets the central nervous system (CNS), leading to potentially severe neurological complications. The neurovascular unit plays a fundamental role in the CNS and in the neuroinvasion of TBEV. However, the role of human brain pericytes, a key component of the neurovascular unit, during TBEV infection has not yet been elucidated. In this study, TBEV infection of the primary human brain perivascular pericytes was investigated with highly virulent Hypr strain and mildly virulent Neudoerfl strain. We used Luminex assay to measure cytokines/chemokines and growth factors. Both viral strains showed comparable replication kinetics, peaking at 3 days post infection (dpi). Intracellular viral RNA copies peaked at 6 dpi for Hypr and 3 dpi for Neudoerfl cultures. According to immunofluorescence staining, only small proportion of pericytes were infected (3% for Hypr and 2% for Neudoerfl), and no cytopathic effect was observed in the infected cells. In cell culture supernatants, IL-6 production was detected at 3 dpi, together with slight increases in IL-15 and IL-4, but IP-10, RANTES and MCP-1 were the main chemokines released after TBEV infection. These chemokines play key roles in both immune defense and immunopathology during TBE. This study suggests that pericytes are an important source of these signaling molecules during TBEV infection in the brain.

• Klíčová slova
• CCL5, CXCL10, chemokine, flavivirus, human pericytes, infection, inflammation, tick-borne encephalitis virus,
• MeSH
• chemokin CCL5 * metabolismus   MeSH
• chemokin CXCL10 * metabolismus   MeSH
• cytokiny metabolismus   MeSH
• klíšťová encefalitida * virologie   metabolismus   MeSH
• kultivované buňky MeSH
• lidé MeSH
• mozek * virologie   metabolismus   patologie   MeSH
• pericyty * virologie   metabolismus   MeSH
• replikace viru MeSH
• viry klíšťové encefalitidy * fyziologie   patogenita   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• CCL5 protein, human MeSH Prohlížeč
• chemokin CCL5 * MeSH
• chemokin CXCL10 * MeSH
• CXCL10 protein, human MeSH Prohlížeč
• cytokiny MeSH

We present structures of three immature tick-borne encephalitis virus (TBEV) isolates. Our atomic models of the major viral components, the E and prM proteins, indicate that the pr domains of prM have a critical role in holding the heterohexameric prM3E3 spikes in a metastable conformation. Destabilization of the prM furin-sensitive loop at acidic pH facilitates its processing. The prM topology and domain assignment in TBEV is similar to the mosquito-borne Binjari virus, but is in contrast to other immature flavivirus models. These results support that prM cleavage, the collapse of E protein ectodomains onto the virion surface, the large movement of the membrane domains of both E and M, and the release of the pr fragment from the particle render the virus mature and infectious. Our work favors the collapse model of flavivirus maturation warranting further studies of immature flaviviruses to determine the sequence of events and mechanistic details driving flavivirus maturation.

• MeSH
• Flavivirus fyziologie   MeSH
• klíšťová encefalitida virologie   MeSH
• lidé MeSH
• molekulární modely MeSH
• proteiny virového obalu * chemie   metabolismus   MeSH
• virion MeSH
• viry klíšťové encefalitidy * fyziologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• proteiny virového obalu * MeSH