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 MeSH
The life cycle of enveloped viruses is closely linked to host-cell lipids. However, changes in lipid metabolism during infections with the tick-borne encephalitis virus (TBEV) have not been described. TBEV is a medically important orthoflavivirus, which is endemic to many parts of Europe and Asia. In the present study, we performed targeted lipidomics with HPLC-MS/MS to evaluate changes in phospholipid and sphingolipid concentrations in TBEV-infected human neuronal SK-N-SH cells. TBEV infections significantly increased phosphatidylcholine, phosphatidylinositol, and phosphatidylserine levels within 48 h post-infection (hpi). Sphingolipids were slightly increased in dihydroceramides within 24 hpi. Later, at 48 hpi, the contents of sphinganine, dihydroceramides, ceramides, glucosylceramides, and ganglioside GD3 were elevated. On the other hand, sphingosine-1-phosphate content was slightly reduced in TBEV-infected cells. Changes in sphingolipid concentrations were accompanied by suppressed expression of a majority of the genes linked to sphingolipid and glycosphingolipid metabolism. Furthermore, we found that a pharmacological inhibitor of sphingolipid synthesis, fenretinide (4-HPR), inhibited TBEV infections in SK-N-SH cells. Taken together, our results suggested that both structural and signaling functions of lipids could be affected during TBEV infections. These changes might be connected to virus propagation and/or host-cell defense.
- MeSH
- buněčné linie MeSH
- fosfolipidy * metabolismus MeSH
- interakce hostitele a patogenu MeSH
- lidé MeSH
- lipidomika MeSH
- metabolismus lipidů MeSH
- neurony * virologie metabolismus MeSH
- sfingolipidy * metabolismus MeSH
- tandemová hmotnostní spektrometrie MeSH
- viry klíšťové encefalitidy * fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Matrix metalloproteinases (MMPs) play an important role in central nervous system infections. We analysed the levels of 8 different MMPs in the cerebrospinal fluid (CSF) of 89 adult patients infected with tick-borne encephalitis (TBE) virus and compared them with the levels in a control group. MMP-9 was the only MMP that showed significantly increased CSF levels in TBE patients. Serum MMP-9 levels were subsequently measured in 101 adult TBE patients at various time points during the neurological phase of TBE and at follow-up. In addition, serum MMP-9 was analysed in 37 paediatric TBE patients. Compared with control levels, both paediatric and adult TBE patients had significantly elevated serum MMP-9 levels. In most adult patients, serum MMP-9 levels peaked at hospital admission, with higher serum MMP-9 levels observed in patients with encephalitis than in patients with meningitis. Elevated serum MMP-9 levels were observed throughout hospitalisation but decreased to normal levels at follow-up. Serum MMP-9 levels correlated with clinical course, especially in patients heterozygous for the single-nucleotide polymorphism rs17576 (A/G; Gln279Arg) in the MMP9 gene. The results highlight the importance of MMP-9 in the pathogenesis of TBE and suggest that serum MMP-9 may serve as a promising bioindicator of TBE in both paediatric and adult TBE patients.
- MeSH
- biologické markery MeSH
- dítě MeSH
- dospělí MeSH
- jednonukleotidový polymorfismus MeSH
- klíšťová encefalitida * diagnóza mozkomíšní mok MeSH
- lidé MeSH
- matrixová metaloproteinasa 9 genetika MeSH
- viry klíšťové encefalitidy * genetika MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Tick-borne encephalitis (TBE) is a neuroviral disease that ranges in severity from a mild febrile illness to a severe and life-threatening meningoencephalitis or encephalomyelitis. There is increasing evidence that susceptibility to tick-borne encephalitis virus (TBEV)-induced disease and its severity are largely influenced by host genetic factors, in addition to other virus- and host-related factors. In this study, we investigated the contribution of selected single nucleotide polymorphisms (SNPs) in innate immunity genes to predisposition to TBE in humans. More specifically, we investigated a possible association between SNPs rs304478 and rs303212 in the gene Interferon Induced Protein With Tetratricopeptide Repeats 1 (IFIT1), rs7070001 and rs4934470 in the gene Interferon Induced Protein With Tetratricopeptide Repeats 2 (IFIT2), and RIG-I (Retinoic acid-inducible gene I) encoding gene DDX58 rs311795343, rs10813831, rs17217280 and rs3739674 SNPs with predisposition to TBE in population of the Czech Republic, where TBEV is highly endemic. Genotypic and allelic frequencies for these SNPs were analyzed in 247 nonimmunized TBE patients and compared with 204 control subjects. The analysis showed an association of IFIT1 rs304478 SNP and DDX58 rs3739674 and rs17217280 SNPs with predisposition to TBE in the Czech population indicating novel risk factors for clinical TBE but not for disease severity. These results also highlight the role of innate immunity genes in TBE pathogenesis.
- MeSH
- genotyp MeSH
- interferony genetika MeSH
- jednonukleotidový polymorfismus MeSH
- klíšťová encefalitida * genetika epidemiologie MeSH
- lidé MeSH
- přirozená imunita genetika MeSH
- viry klíšťové encefalitidy * genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Tick-borne encephalitis (TBE) is a severe neuroinfection of humans. Dogs are also commonly infected with tick-borne encephalitis virus (TBEV). These infections are usually asymptomatic, but sometimes show clinical signs similar to those seen in humans and can be fatal. To date, there is no TBEV vaccine available for use in dogs. To address this need, a TBEV vaccine candidate for dogs based on inactivated whole virus antigen was developed. The safety, immunogenicity, and efficacy of the vaccine candidate were tested in mice as the preclinical model and in dogs as the target organism. The vaccine was well tolerated in both species and elicited the production of specific anti-TBEV antibodies with virus neutralising activity. Vaccination of mice provided complete protection against the development of fatal TBE. Immunisation of dogs prevented the development of viremia after challenge infection. Therefore, the developed vaccine candidate is promising to protect dogs from severe TBEV infections.
- MeSH
- imunizace MeSH
- klíšťová encefalitida * prevence a kontrola veterinární MeSH
- lidé MeSH
- myši MeSH
- protilátky virové MeSH
- psi MeSH
- vakcinace MeSH
- virové vakcíny * MeSH
- viry klíšťové encefalitidy * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- psi MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has prompted great interest in novel broad-spectrum antivirals, including perylene-related compounds. In the present study, we performed a structure-activity relationship analysis of a series of perylene derivatives, which comprised a large planar perylene residue, and structurally divergent polar groups connected to the perylene core by a rigid ethynyl or thiophene linker. Most of the tested compounds did not exhibit significant cytotoxicity towards multiple cell types susceptible to SARS-CoV-2 infection, and did not change the expressions of cellular stress-related genes under normal light conditions. These compounds showed nanomolar or sub-micromolar dose-dependent anti-SARS-CoV-2 activity, and also suppressed the in vitro replication of feline coronavirus (FCoV), also termed feline infectious peritonitis virus (FIPV). Perylene compounds exhibited high affinity for liposomal and cellular membranes, and efficiently intercalated into the envelopes of SARS-CoV-2 virions, thereby blocking the viral-cell fusion machinery. Furthermore, the studied compounds were demonstrated to be potent photosensitizers, generating reactive oxygen species (ROS), and their anti-SARS-CoV-2 activities were considerably enhanced after irradiation with blue light. Our results indicated that photosensitization is the major mechanism underlying the anti-SARS-CoV-2 activity of perylene derivatives, with these compounds completely losing their antiviral potency under red light. Overall, perylene-based compounds are broad-spectrum antivirals against multiple enveloped viruses, with antiviral action based on light-induced photochemical damage (ROS-mediated, likely singlet oxygen-mediated), causing impairment of viral membrane rheology.
- MeSH
- antivirové látky farmakologie chemie MeSH
- COVID-19 * MeSH
- kočky MeSH
- perylen * farmakologie MeSH
- reaktivní formy kyslíku MeSH
- SARS-CoV-2 MeSH
- singletový kyslík MeSH
- virion MeSH
- virový obal MeSH
- zvířata MeSH
- Check Tag
- kočky MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Extensive axonal and neuronal loss is the main cause of severe manifestations and poor outcomes in tick-borne encephalitis (TBE). Phosphorylated neurofilament heavy subunit (pNF-H) is an essential component of axons, and its detection in cerebrospinal fluid (CSF) or serum can indicate the degree of neuroaxonal damage. We examined the use of pNF-H as a biomarker of neuroaxonal injury in TBE. In 89 patients with acute TBE, we measured CSF levels of pNF-H and 3 other markers of brain injury (glial fibrillary acidic protein, S100B and ubiquitin C-terminal hydrolase L1) and compared the results to those for patients with meningitis of other aetiology and controls. Serum pNF-H levels were measured in 80 patients and compared with findings for 90 healthy blood donors. TBE patients had significantly (P<0.001) higher CSF pNF-H levels than controls as early as hospital admission. Serum pNF-H concentrations were significantly higher in samples from TBE patients collected at hospital discharge (P<0.0001) than in controls. TBE patients with the highest peak values of serum pNF-H, exceeding 10 000 pg ml-1, had a very severe disease course, with coma or tetraplegia. Patients requiring intensive care had significantly higher serum pNF-H levels than other TBE patients (P<0.01). Elevated serum pNF-H values were also observed in patients with incomplete recovery (P<0.05). Peak serum pNF-H levels correlated positively with the duration of hospitalization (P=0.005). Measurement of pNF-H levels in TBE patients might be useful for assessing disease severity and determining prognosis.
- MeSH
- biologické markery MeSH
- intermediární filamenta MeSH
- klíšťová encefalitida * diagnóza MeSH
- lidé MeSH
- prognóza MeSH
- progrese nemoci MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Positive-sense single-stranded RNA (+RNA) viruses have proven to be important pathogens that are able to threaten and deeply damage modern societies, as illustrated by the ongoing COVID-19 pandemic. Therefore, compounds active against most or many +RNA viruses are urgently needed. Here, we present PR673, a helquat-like compound that is able to inhibit the replication of SARS-CoV-2 and tick-borne encephalitis virus in cell culture. Using in vitro polymerase assays, we demonstrate that PR673 inhibits RNA synthesis by viral RNA-dependent RNA polymerases (RdRps). Our results illustrate that the development of broad-spectrum non-nucleoside inhibitors of RdRps is feasible.
- MeSH
- COVID-19 * MeSH
- lidé MeSH
- pandemie MeSH
- RNA-dependentní RNA-polymerasa MeSH
- SARS-CoV-2 MeSH
- viry klíšťové encefalitidy * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Neutralizing antibodies that target the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein are among the most promising approaches against COVID-191,2. A bispecific IgG1-like molecule (CoV-X2) has been developed on the basis of C121 and C135, two antibodies derived from donors who had recovered from COVID-193. Here we show that CoV-X2 simultaneously binds two independent sites on the RBD and, unlike its parental antibodies, prevents detectable spike binding to the cellular receptor of the virus, angiotensin-converting enzyme 2 (ACE2). Furthermore, CoV-X2 neutralizes wild-type SARS-CoV-2 and its variants of concern, as well as escape mutants generated by the parental monoclonal antibodies. We also found that in a mouse model of SARS-CoV-2 infection with lung inflammation, CoV-X2 protects mice from disease and suppresses viral escape. Thus, the simultaneous targeting of non-overlapping RBD epitopes by IgG-like bispecific antibodies is feasible and effective, and combines the advantages of antibody cocktails with those of single-molecule approaches.
- MeSH
- angiotensin konvertující enzym 2 antagonisté a inhibitory genetika metabolismus MeSH
- COVID-19 imunologie prevence a kontrola virologie MeSH
- Dependovirus genetika MeSH
- epitopy B-lymfocytární chemie imunologie MeSH
- farmakoterapie COVID-19 MeSH
- glykoprotein S, koronavirus antagonisté a inhibitory chemie imunologie MeSH
- imunitní únik genetika MeSH
- imunoglobulin G imunologie MeSH
- lidé MeSH
- modely nemocí na zvířatech MeSH
- monoklonální protilátky imunologie MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- neutralizující protilátky imunologie terapeutické užití MeSH
- protilátky bispecifické imunologie terapeutické užití MeSH
- SARS-CoV-2 genetika imunologie MeSH
- tělesná hmotnost MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH