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1.
Hepatology ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38728662

RESUMEN

BACKGROUND AND AIMS: The hepatitis E virus (HEV) is estimated to be responsible for 70,000 deaths annually, yet therapy options remain limited. In the pursuit of effective antiviral therapies, targeting viral entry holds promise and has proven effective for other viruses. However, the precise mechanisms and host factors required during HEV entry remain unclear. Cellular proteases have emerged as host factors required for viral surface protein activation and productive cell entry by many viruses. Hence, we investigated the functional requirement and therapeutic potentials of cellular proteases during HEV infection. APPROACH AND RESULTS: Using our established HEV cell culture model and subgenomic HEV replicons, we found that blocking lysosomal cathepsins (CTS) with small molecule inhibitors, impedes HEV infection without affecting replication. Most importantly, the pan-cathepsin inhibitor K11777 suppressed HEV infections with an EC50 of ~ 0.01 nM. Inhibition by K11777, devoid of notable toxicity in hepatoma cells, was also observed in HepaRG and primary human hepatocytes. Furthermore, through time-of-addition and RNAscope experiments, we confirmed that HEV entry is blocked by inhibition of cathepsins. Cathepsin L (CTSL) knockout cells were less permissive to HEV, suggesting that CTSL is critical for HEV infection. Finally, we observed cleavage of the glycosylated ORF2 protein and virus particles by recombinant CTSL. CONCLUSIONS: In summary, our study highlights the pivotal role of lysosomal cathepsins, especially CTSL, in the HEV entry process. The profound anti-HEV efficacy of the pan-cathepsin inhibitor, K11777, especially with its notable safety profile in primary cells, further underscores its potential as a therapeutic candidate.

3.
Curr Opin Microbiol ; 79: 102474, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615394

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019, contributes to neurological pathologies in nearly 30% of patients, extending beyond respiratory symptoms. These manifestations encompass disorders of both the peripheral and central nervous systems, causing among others cerebrovascular issues and psychiatric manifestations during the acute and/or post-acute infection phases. Despite ongoing research, uncertainties persist about the precise mechanism the virus uses to infiltrate the central nervous system and the involved entry portals. This review discusses the potential entry routes, including hematogenous and anterograde transport. Furthermore, we explore variations in neurotropism, neurovirulence, and neurological manifestations among pandemic-associated variants of concern. In conclusion, SARS-CoV-2 can infect numerous cells within the peripheral and central nervous system, provoke inflammatory responses, and induce neuropathological changes.

4.
Emerg Infect Dis ; 30(5): 934-940, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38666600

RESUMEN

To determine the kinetics of hepatitis E virus (HEV) in asymptomatic persons and to evaluate viral load doubling time and half-life, we retrospectively tested samples retained from 32 HEV RNA-positive asymptomatic blood donors in Germany. Close-meshed monitoring of viral load and seroconversion in intervals of ≈4 days provided more information about the kinetics of asymptomatic HEV infections. We determined that a typical median infection began with PCR-detectable viremia at 36 days and a maximum viral load of 2.0 × 104 IU/mL. Viremia doubled in 2.4 days and had a half-life of 1.6 days. HEV IgM started to rise on about day 33 and peaked on day 36; IgG started to rise on about day 32 and peaked on day 53. Although HEV IgG titers remained stable, IgM titers became undetectable in 40% of donors. Knowledge of the dynamics of HEV viremia is useful for assessing the risk for transfusion-transmitted hepatitis E.


Asunto(s)
Donantes de Sangre , Virus de la Hepatitis E , Hepatitis E , ARN Viral , Carga Viral , Viremia , Humanos , Hepatitis E/epidemiología , Hepatitis E/virología , Virus de la Hepatitis E/genética , Virus de la Hepatitis E/inmunología , Masculino , Adulto , Inmunoglobulina M/sangre , Femenino , Inmunoglobulina G/sangre , Cinética , Persona de Mediana Edad , Infecciones Asintomáticas/epidemiología , Estudios Retrospectivos , Anticuerpos Antihepatitis/sangre , Alemania/epidemiología , Adulto Joven
5.
J Appl Microbiol ; 135(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38439676

RESUMEN

AIMS: We aimed to develop a method to assess the virucidal performance of domestic laundry in a lab-scale washing machine (Rotawash) based on EN 17658. METHODS AND RESULTS: For method development, virus recovery was investigated after drying on cotton carriers for three test viruses murine norovirus (MNV), modified vaccinia virus Ankara (MVA), and bovine coronavirus (BCoV), followed by washing simulations in flasks and Rotawash. MNV and MVA demonstrated sufficient recovery from carriers after drying and washing (up to 40°C and 60 min). BCoV exhibited lower recovery, indicating less relevance as a test virus. Rotawash efficacy tests conducted with MNV, a resistant, non-enveloped virus, showed limited efficacy of a bleach-free detergent, aligning with results from a domestic washing machine. Rotawash washes achieved higher reductions in infectious virus titers than suspension tests, indicating the role of washing mechanics in virus removal. CONCLUSIONS: This study established a practical method to test the virucidal efficacy of laundry detergents in Rotawash, simulating domestic washing.


Asunto(s)
Detergentes , Norovirus , Bovinos , Animales , Ratones , Detergentes/farmacología , Textiles
6.
JHEP Rep ; 6(3): 100989, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38434938

RESUMEN

Background & Aims: In the absence of a hepatitis E virus (HEV)-specific antiviral treatment, sofosbuvir has recently been shown to have antiviral activity against HEV in vivo. However, a variant, A1343V, that is strongly associated with viral relapse impedes treatment success. In this study, we investigated the occurrence of variants during sofosbuvir and ribavirin treatment in vivo and assessed the sensitivity of resistance-associated variants to concurrent treatment in cell culture. Methods: Two patients with chronic HEV infection that did not clear infection under ribavirin treatment were subsequently treated with a combination of sofosbuvir and ribavirin. We determined response to treatment by measuring liver enzymes and viral load in blood and stool. Moreover, we analyzed viral evolution using polymerase-targeted high-throughput sequencing and assessed replication fitness of resistance-associated variants using a HEV replicon system. Results: Combination treatment was successful in decreasing viral load towards the limit of quantification. However, during treatment sustained virological response was not achieved. Variants associated with sofosbuvir or ribavirin treatment emerged during treatment, including A1343V and G1634R. Moreover, A1343V, as a single or double mutation with G1634R, was associated with sofosbuvir resistance during concomitant treatment in vitro. Conclusions: These results highlight the importance of variant profiling during antiviral treatment of patients with chronic infection. Understanding how intra-host viral evolution impedes treatment success will help guide the design of next-generation antivirals. Impact and implications: The lack of hepatitis E virus (HEV)-specific antivirals to treat chronic infection remains a serious health burden. Although ribavirin, interferon and sofosbuvir have been reported as anti-HEV drugs, not all patients are eligible for treatment or clear infection, since resistant-associated variants can rapidly emerge. In this study, we analyzed the efficacy of sofosbuvir and ribavirin combination treatment in terms of HEV suppression, the emergence of resistance-associated variants and their ability to escape treatment inhibition in vitro. Our results provide novel insights into evolutionary dynamics of HEV during treatment and thus will help guide the design of next-generation antivirals.

7.
J Virol ; 98(3): e0192123, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38319104

RESUMEN

Hepatitis C virus (HCV) infection progresses to chronicity in the majority of infected individuals. Its high intra-host genetic variability enables HCV to evade the continuous selection pressure exerted by the host, contributing to persistent infection. Utilizing a cell culture-adapted HCV population (p100pop) which exhibits increased replicative capacity in various liver cell lines, this study investigated virus and host determinants that underlie enhanced viral fitness. Characterization of a panel of molecular p100 clones revealed that cell culture adaptive mutations optimize a range of virus-host interactions, resulting in expanded cell tropism, altered dependence on the cellular co-factor micro-RNA 122 and increased rates of virus spread. On the host side, comparative transcriptional profiling of hepatoma cells infected either with p100pop or its progenitor virus revealed that enhanced replicative fitness correlated with activation of endoplasmic reticulum stress signaling and the unfolded protein response. In contrast, infection of primary human hepatocytes with p100pop led to a mild attenuation of virion production which correlated with a greater induction of cell-intrinsic antiviral defense responses. In summary, long-term passage experiments in cells where selective pressure from innate immunity is lacking improves multiple virus-host interactions, enhancing HCV replicative fitness. However, this study further indicates that HCV has evolved to replicate at low levels in primary human hepatocytes to minimize innate immune activation, highlighting that an optimal balance between replicative fitness and innate immune induction is key to establish persistence. IMPORTANCE: Hepatitis C virus (HCV) infection remains a global health burden with 58 million people currently chronically infected. However, the detailed molecular mechanisms that underly persistence are incompletely defined. We utilized a long-term cell culture-adapted HCV, exhibiting enhanced replicative fitness in different human liver cell lines, in order to identify molecular principles by which HCV optimizes its replication fitness. Our experimental data revealed that cell culture adaptive mutations confer changes in the host response and usage of various host factors. The latter allows functional flexibility at different stages of the viral replication cycle. However, increased replicative fitness resulted in an increased activation of the innate immune system, which likely poses boundary for functional variation in authentic hepatocytes, explaining the observed attenuation of the adapted virus population in primary hepatocytes.


Asunto(s)
Aptitud Genética , Hepacivirus , Hepatocitos , Interacciones Microbiota-Huesped , Inmunidad Innata , Mutación , Humanos , Células Cultivadas , Estrés del Retículo Endoplásmico , Aptitud Genética/genética , Aptitud Genética/inmunología , Hepacivirus/genética , Hepacivirus/crecimiento & desarrollo , Hepacivirus/inmunología , Hepacivirus/fisiología , Hepatitis C/inmunología , Hepatitis C/virología , Hepatocitos/inmunología , Hepatocitos/virología , Interacciones Microbiota-Huesped/inmunología , MicroARNs/metabolismo , Pase Seriado , Respuesta de Proteína Desplegada , Tropismo Viral , Virión/crecimiento & desarrollo , Virión/metabolismo , Replicación Viral/genética , Replicación Viral/inmunología
8.
Liver Int ; 44(3): 637-643, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38291853

RESUMEN

Hepatitis E virus (HEV) is prevalent worldwide and can cause persistent infection with severe morbidity. Antiviral treatment approaches can lead to the emergence of viral variants encoding escape mutations that may impede viral clearance. The frequency of these variants remains unknown in the human population as well as environment due to limited comprehensive data on HEV diversity. In this study, we investigated the HEV prevalence and diversity of circulating variants in environmental samples, that is, wastewater and rivers from North-Rhine Westphalia, Germany. HEV prevalence could be determined with 73% of samples tested positive for viral RNA via qRT-PCR. Using high-throughput sequencing, we were able to assess the overall genetic diversity in these samples and identified the presence of clinically relevant variants associated with drug resistance. In summary, monitoring variants from environmental samples could provide valuable insights into estimating HEV prevalence and identifying circulating variants that can impact treatment outcome.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Humanos , Virus de la Hepatitis E/genética , Aguas Residuales , Hepatitis E/diagnóstico , Hepatitis E/tratamiento farmacológico , Hepatitis E/epidemiología , Filogenia , Prevalencia , ARN Viral/genética
9.
J Med Chem ; 67(1): 289-321, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38127656

RESUMEN

The synthesis of a library of halogenated rocaglate derivatives belonging to the flavagline class of natural products, of which silvestrol is the most prominent example, is reported. Their antiviral activity and cytotoxicity profile against a wide range of pathogenic viruses, including hepatitis E, Chikungunya, Rift Valley Fever virus and SARS-CoV-2, were determined. The incorporation of halogen substituents at positions 4', 6 and 8 was shown to have a significant effect on the antiviral activity of rocaglates, some of which even showed enhanced activity compared to CR-31-B and silvestrol.


Asunto(s)
Fiebre Chikungunya , Virus de la Hepatitis E , Virus , Animales , Antivirales/farmacología
10.
bioRxiv ; 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-38045248

RESUMEN

Hepatitis C virus (HCV) infection progresses to chronicity in the majority of infected individuals. Its high intra-host genetic variability enables HCV to evade the continuous selection pressure exerted by the host, contributing to persistent infection. Utilizing a cell culture adapted HCV population (p100pop) which exhibits increased replicative capacity in various liver cell lines, this study investigated virus and host determinants which underlie enhanced viral fitness. Characterization of a panel of molecular p100 clones revealed that cell culture adaptive mutations optimize a range of virus-host interactions, resulting in expanded cell tropism, altered dependence on the cellular co-factor micro-RNA 122 and increased rates of virus spread. On the host side, comparative transcriptional profiling of hepatoma cells infected either with p100pop or its progenitor virus revealed that enhanced replicative fitness correlated with activation of endoplasmic reticulum stress signaling and the unfolded protein response. In contrast, infection of primary human hepatocytes with p100pop led to a mild attenuation of virion production which correlated with a greater induction of cell-intrinsic antiviral defense responses. In summary, long-term passage experiments in cells where selective pressure from innate immunity is lacking improves multiple virus-host interactions, enhancing HCV replicative fitness. However, this study further indicates that HCV has evolved to replicate at low levels in primary human hepatocytes to minimize innate immune activation, highlighting that an optimal balance between replicative fitness and innate immune induction is key to establishing persistence.

12.
J Med Virol ; 95(12): e29312, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38100621

RESUMEN

For the prevention of infectious diseases, knowledge about potential transmission routes is essential. Pathogens can be transmitted directly (i.e. respiratory droplets, hand-to-hand contact) or indirectly via contaminated surfaces (fomites). In particular, frequently touched objects/surfaces may serve as transmission vehicles for different clinically relevant bacterial, fungal, and viral pathogens. Banknotes and coins offer ample surface area and are frequently exchanged between individuals. Consequently, many concerns have been raised in the recent past, that banknotes and coins could serve as vectors for the transmission of disease-causing microorganisms. This review summarizes the latest research on the potential of paper currency and coins to serve as sources of pathogenic viral, bacterial, and fungal agents. In contrast to the current perception of banknotes and coins as important transmission vehicles, current evidence suggests, that banknotes and coins do not pose a particular risk of pathogen infection for the public.


Asunto(s)
Fómites , Numismática , Humanos , Bacterias/genética
13.
Viruses ; 15(11)2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-38005856

RESUMEN

Viral disinfection is important for medical facilities, the food industry, and the veterinary field, especially in terms of controlling virus outbreaks. Therefore, standardized methods and activity levels are available for these areas. Usually, disinfectants used in these areas are characterized by their activity against test organisms (i.e., viruses, bacteria, and/or yeasts). This activity is usually determined using a suspension test in which the test organism is incubated with the respective disinfectant in solution to assess its bactericidal, yeasticidal, or virucidal activity. In addition, carrier methods that more closely reflect real-world applications have been developed, in which microorganisms are applied to the surface of a carrier (e.g., stainless steel frosted glass, or polyvinyl chloride (PVC)) and then dried. However, to date, no standardized methods have become available for addressing genetically modified vectors or disinfection-resistant oncolytic viruses such as the H1-parvovirus. Particularly, such non-enveloped viruses, which are highly resistant to disinfectants, are not taken into account in European standards. This article proposes a new activity claim known as "virucidal activity PLUS", summarizes the available methods for evaluating the virucidal activity of chemical disinfectants against genetically modified organisms (GMOs) using current European standards, including the activity against highly resistant parvoviridae such as the adeno-associated virus (AAV), and provides guidance on the selection of disinfectants for pharmaceutical manufacturers, laboratories, and clinical users.


Asunto(s)
Desinfectantes , Infecciones por Parvoviridae , Parvovirus , Virus , Humanos , Desinfectantes/farmacología , Desinfección/métodos , Virus/genética
14.
Can J Vet Res ; 87(3): 169-175, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37397641

RESUMEN

Equine parvovirus-hepatitis (EqPV-H) was first reported from the serum and liver tissue of a horse diagnosed with Theiler's disease in the United States in 2018. Theiler's disease, also known as equine serum hepatitis, is a severe hepatitis with fulminant hepatic necrosis. The disease has most frequently been reported following the administration of equine-origin biological products; however, it has also been reported in in-contact horses with no prior biologic administration. EqPV-H has been detected in clinically healthy horses in North America (USA, Canada), Europe (Germany, Austria, Slovenia), Asia (China, South Korea), and South America (Brazil). Previous prevalence studies conducted worldwide have shown the presence of EqPV-H DNA in serum or plasma ranging from 3.2 to 19.8%. This study investigated the prevalence of EqPV-H DNA in 170 healthy broodmares of various breeds located on 37 farms in southern Ontario, Canada. The occurrence of EqPV-H infection was determined by quantitative PCR for EqPV-H DNA in serum samples. The effects of age, breed, season, pregnancy status, and equine herpesvirus-1 (EHV-1) vaccination history on EqPV-H status were also investigated. There was a prevalence of 15.9% (27/170) with viral loads of EqPV-H ranging from detectable to 2900 copies/mL. Statistical analysis showed that increasing age was a significant factor in the detection of EqPV-H DNA. Neither breed, season, pregnancy status, nor EHV-1 vaccination history was significant in predicting EqPV-H infection status.


L'hépatite à parvovirus équin (EqPV-H) a été signalée pour la première fois à partir du sérum et du tissu hépatique d'un cheval diagnostiqué avec la maladie de Theiler aux États-Unis en 2018. La maladie de Theiler, également connue sous le nom d'hépatite sérique équine, est une hépatite sévère avec nécrose hépatique fulminante. La maladie a été le plus souvent rapportée à la suite de l'administration de produits biologiques d'origine équine; cependant, il a également été signalé chez des chevaux en contact sans administration préalable de produit biologique. EqPV-H a été détecté chez des chevaux cliniquement sains en Amérique du Nord (États-Unis, Canada), en Europe (Allemagne, Autriche, Slovénie), en Asie (Chine, Corée du Sud) et en Amérique du Sud (Brésil). Des études de prévalence antérieures menées dans le monde entier ont montré la présence d'ADN EqPV-H dans le sérum ou le plasma allant de 3,2 à 19,8 %. Cette étude a examiné la prévalence de l'ADN EqPV-H chez 170 poulinières en bonne santé de différentes races situées dans 37 fermes du sud de l'Ontario, au Canada. La survenue d'une infection par EqPV-H a été déterminée par PCR quantitative pour l'ADN d'EqPV-H dans des échantillons de sérum. Les effets de l'âge, de la race, de la saison, de l'état de grossesse et des antécédents de vaccination contre l'herpèsvirus équin-1 (EHV-1) sur le statut EqPV-H ont également été étudiés. Il y avait une prévalence de 15,9 % (27/170) avec des charges virales d'EqPV-H allant de détectable à 2900 copies/mL. L'analyse statistique a montré que l'augmentation de l'âge était un facteur significatif dans la détection de l'ADN EqPV-H. Ni la race, ni la saison, ni l'état de grossesse, ni les antécédents de vaccination contre l'EHV-1 n'étaient significatifs pour prédire l'état de l'infection par l'EqPV-H.(Traduit par Docteur Serge Messier).


Asunto(s)
Hepatitis Viral Animal , Hepatitis , Infecciones por Herpesviridae , Enfermedades de los Caballos , Infecciones por Parvoviridae , Parvovirus , Animales , Caballos , Embarazo , Femenino , Parvovirus/genética , Infecciones por Parvoviridae/epidemiología , Infecciones por Parvoviridae/veterinaria , Ontario/epidemiología , Prevalencia , Hepatitis Viral Animal/epidemiología , Enfermedades de los Caballos/epidemiología , Infecciones por Herpesviridae/veterinaria
15.
Antiviral Res ; 217: 105690, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37517633

RESUMEN

Hepatitis E virus (HEV) usually causes a self-limiting disease, but especially immunocompromised individuals are at risk to develop a chronic and severe course of infection. Janus kinase (JAK) inhibitors (JAKi) are a novel drug class for the treatment of autoimmune inflammatory rheumatic disease (AIRD). As JAKs play a key role in innate immunity, viral infections and reactivations are frequently reported during JAKi treatment in AIRD patients. The aim of this study was to characterize the influence of JAKis on HEV replication. To this end, we evaluated liver enzymes of an AIRD patient under JAKi therapy with hepatitis E. Further, experiments with HEV (Kernow-C1 p6) were performed by infection of primary human hepatocytes (PHHs) followed by immunofluorescence staining of viral markers and transcriptomic analysis. Infection experiments in PHHs displayed an up to 50-fold increase of progeny virus production during JAKi treatment and transcriptomic analysis revealed induction of antiviral programs during infection. Upregulation of interferon-stimulated genes (ISG) was perturbed in the presence of JAKis, concomitant with elevated HEV RNA levels. The obtained results suggest that therapeutic JAK inhibition increases HEV replication by modulating the HEV-triggered immune response. Therefore, JAKi treatment and the occurrence of elevated liver enzymes requires a monitoring of potential HEV infections.


Asunto(s)
Virus de la Hepatitis E , Hepatitis E , Humanos , Virus de la Hepatitis E/genética , Quinasas Janus , Interferones/farmacología , Antivirales/farmacología , Antivirales/uso terapéutico , Replicación Viral
16.
J Cancer Res Clin Oncol ; 149(12): 10633-10644, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37300723

RESUMEN

PURPOSE: The SARS-CoV-2 Omicron variant of concern (VOC) and subvariants like BQ.1.1 demonstrate immune evasive potential. Little is known about the efficacy of booster vaccinations regarding this VOC and subvariants in cancer patients. This study is among the first to provide data on neutralizing antibodies (nAb) against BQ.1.1. METHODS: Cancer patients at our center were prospectively enrolled between 01/2021 and 02/2022. Medical data and blood samples were collected at enrollment and before and after every SARS-CoV-2 vaccination, at 3 and 6 months. RESULTS: We analyzed 408 samples from 148 patients (41% female), mainly with solid tumors (85%) on active therapy (92%; 80% chemotherapy). SARS-CoV-2 IgG and nAb titers decreased over time, however, significantly increased following third vaccination (p < 0.0001). NAb (ND50) against Omicron BA.1 was minimal prior and increased significantly after the third vaccination (p < 0.0001). ND50 titers against BQ.1.1 after the third vaccination were significantly lower than against BA.1 and BA.4/5 (p < 0.0001) and undetectable in half of the patients (48%). Factors associated with impaired immune response were hematologic malignancies, B cell depleting therapy and higher age. Choice of vaccine, sex and treatment with chemo-/immunotherapy did not influence antibody response. Patients with breakthrough infections had significantly lower nAb titers after both 6 months (p < 0.001) and the third vaccination (p = 0.018). CONCLUSION: We present the first data on nAb against BQ.1.1 following the third vaccination in cancer patients. Our results highlight the threat that new emerging SARS-CoV-2 variants pose to cancer patients and support efforts to apply repeated vaccines. Since a considerable number of patients did not display an adequate immune response, continuing to exhibit caution remains reasonable.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Neoplasias , Femenino , Humanos , Masculino , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Neoplasias/complicaciones , SARS-CoV-2 , Vacunación
17.
Hepatology ; 78(6): 1882-1895, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37334496

RESUMEN

BACKGROUND AND AIMS: Chronic HEV infections remain a serious problem in immunocompromised patients, as specifically approved antiviral drugs are unavailable. In 2020, a 24-week multicenter phase II pilot trial was carried out, evaluating the nucleotide analog sofosbuvir by treating nine chronically HEV-infected patients with sofosbuvir (Trial Number NCT03282474). During the study, antiviral therapy reduced virus RNA levels initially but did not lead to a sustained virologic response. Here, we characterize the changes in HEV intrahost populations during sofosbuvir treatment to identify the emergence of treatment-associated variants. APPROACH AND RESULTS: We performed high-throughput sequencing on RNA-dependent RNA polymerase sequences to characterize viral population dynamics in study participants. Subsequently, we used an HEV-based reporter replicon system to investigate sofosbuvir sensitivity in high-frequency variants. Most patients had heterogenous HEV populations, suggesting high adaptability to treatment-related selection pressures. We identified numerous amino acid alterations emerging during treatment and found that the EC 50 of patient-derived replicon constructs was up to ~12-fold higher than the wild-type control, suggesting that variants associated with lower drug sensitivity were selected during sofosbuvir treatment. In particular, a single amino acid substitution (A1343V) in the finger domain of ORF1 could reduce susceptibility to sofosbuvir significantly in 8 of 9 patients. CONCLUSIONS: In conclusion, viral population dynamics played a critical role during antiviral treatment. High population diversity during sofosbuvir treatment led to the selection of variants (especially A1343V) with lower sensitivity to the drug, uncovering a novel mechanism of resistance-associated variants during sofosbuvir treatment.


Asunto(s)
Hepatitis E , Sofosbuvir , Humanos , Sofosbuvir/farmacología , Sofosbuvir/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico , Hepatitis E/tratamiento farmacológico , Respuesta Virológica Sostenida , Quimioterapia Combinada , Hepacivirus/genética , Genotipo , Resultado del Tratamiento
18.
Emerg Infect Dis ; 29(8): 1690-1692, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37352551

RESUMEN

During 2022, a total of 9,515 asymptomatic healthcare workers of a large hospital in Germany underwent SARS-CoV-2 PCR screening twice weekly. Of 398,784 saliva samples, 3,555 (0.89%) were PCR positive (median cycle threshold value 30). Early identification of infected healthcare workers can help reduce SARS-CoV-2 transmission in the hospital environment.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/epidemiología , Reacción en Cadena de la Polimerasa , Personal de Salud , Alemania/epidemiología , Prueba de COVID-19
19.
Microbiol Spectr ; 11(4): e0128423, 2023 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-37341610

RESUMEN

Mice are refractory to infection with human-tropic hepatitis C virus (HCV), although distantly related rodent hepaciviruses (RHV) circulate in wild rodents. To investigate whether liver intrinsic host factors can exhibit broad restriction against these distantly related hepaciviruses, we focused on Shiftless (Shfl), an interferon (IFN)-regulated gene (IRG) which restricts HCV in humans. Unusually, and in contrast to selected classical IRGs, human and mouse SHFL orthologues (hSHFL and mSHFL, respectively) were highly expressed in hepatocytes in the absence of viral infection, weakly induced by IFN, and highly conserved at the amino acid level (>95%). Replication of both HCV and RHV subgenomic replicons was suppressed by ectopic expression of mSHFL in human or rodent hepatoma cell lines. Gene editing of endogenous mShfl in mouse liver tumor cells increased HCV replication and virion production. Colocalization of mSHFL protein with viral double-stranded RNA (dsRNA) intermediates was confirmed and could be ablated by mutational disruption of the SHFL zinc finger domain, concomitant with a loss of antiviral activity. In summary, these data point to an evolutionarily conserved function for this gene in humans and rodents: SHFL is an ancient antiviral effector which targets distantly related hepaciviruses via restriction of viral RNA replication. IMPORTANCE Viruses have evolved ways to evade or blunt innate cellular antiviral mechanisms within their cognate host species. However, these adaptations may fail when viruses infect new species and can therefore limit cross-species transmission. This may also prevent development of animal models for human-pathogenic viruses. HCV shows a narrow species tropism likely due to distinct human host factor usage and innate antiviral defenses limiting infection of nonhuman liver cells. Interferon (IFN)-regulated genes (IRGs) partially inhibit HCV infection of human cells by diverse mechanisms. Here, we show that mouse Shiftless (mSHFL), a protein that interferes with HCV replication factories, inhibits HCV replication and infection in human and mouse liver cells. We further report that the zinc finger domain of SHFL is important for viral restriction. These findings implicate mSHFL as a host factor that impairs HCV infection of mice and provide guidance for development of HCV animal models needed for vaccine development.


Asunto(s)
Hepacivirus , Hepatitis C , Ratones , Humanos , Animales , Hepacivirus/genética , Antivirales/farmacología , Interferones , Factores de Restricción Antivirales
20.
J Infect Dis ; 228(9): 1227-1230, 2023 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-37129073

RESUMEN

The spread of nonzoonotic monkeypox virus (MPXV) infections necessitates the reevaluation of hygiene measures. To date, only limited data are available on MPXV surface stability. Here, we evaluate the stability of infectious MPXV on stainless steel stored at different temperatures, while using different interfering substances to mimic environmental contamination. MPXV persistence increased with decreasing temperature. Additionally, we were able to show that MPXV could efficiently be inactivated by alcohol- and aldehyde-based surface disinfectants. These findings underline the stability of MPXV on inanimate surfaces and support the recommendations to use alcohol-based disinfectants as prevention measures or in outbreak situations.


Asunto(s)
Desinfectantes , Monkeypox virus , Desinfectantes/farmacología , Etanol , Temperatura , Aldehídos
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