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1.
Immunity ; 53(2): 442-455.e4, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32668194

RESUMO

We profiled adaptive immunity in COVID-19 patients with active infection or after recovery and created a repository of currently >14 million B and T cell receptor (BCR and TCR) sequences from the blood of these patients. The B cell response showed converging IGHV3-driven BCR clusters closely associated with SARS-CoV-2 antibodies. Clonality and skewing of TCR repertoires were associated with interferon type I and III responses, early CD4+ and CD8+ T cell activation, and counterregulation by the co-receptors BTLA, Tim-3, PD-1, TIGIT, and CD73. Tfh, Th17-like, and nonconventional (but not classical antiviral) Th1 cell polarizations were induced. SARS-CoV-2-specific T cell responses were driven by TCR clusters shared between patients with a characteristic trajectory of clonotypes and traceability over the disease course. Our data provide fundamental insight into adaptive immunity to SARS-CoV-2 with the actively updated repository providing a resource for the scientific community urgently needed to inform therapeutic concepts and vaccine development.


Assuntos
Infecções por Coronavirus , Citocinas , Sequenciamento de Nucleotídeos em Larga Escala , Pandemias , Pneumonia Viral , Betacoronavirus , COVID-19 , Humanos , Receptores de Antígenos de Linfócitos B/genética , SARS-CoV-2 , Índice de Gravidade de Doença
2.
Mol Cell ; 80(1): 164-174.e4, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877642

RESUMO

SARS-CoV-2 infections are rapidly spreading around the globe. The rapid development of therapies is of major importance. However, our lack of understanding of the molecular processes and host cell signaling events underlying SARS-CoV-2 infection hinders therapy development. We use a SARS-CoV-2 infection system in permissible human cells to study signaling changes by phosphoproteomics. We identify viral protein phosphorylation and define phosphorylation-driven host cell signaling changes upon infection. Growth factor receptor (GFR) signaling and downstream pathways are activated. Drug-protein network analyses revealed GFR signaling as key pathways targetable by approved drugs. The inhibition of GFR downstream signaling by five compounds prevents SARS-CoV-2 replication in cells, assessed by cytopathic effect, viral dsRNA production, and viral RNA release into the supernatant. This study describes host cell signaling events upon SARS-CoV-2 infection and reveals GFR signaling as a central pathway essential for SARS-CoV-2 replication. It provides novel strategies for COVID-19 treatment.


Assuntos
Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/genética , Fosfatidilinositol 3-Quinase/genética , Receptores de Fatores de Crescimento/genética , Proteínas Virais/genética , Corticosteroides/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Células CACO-2 , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação , Receptores de Fatores de Crescimento/antagonistas & inibidores , Receptores de Fatores de Crescimento/metabolismo , SARS-CoV-2 , Transdução de Sinais , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
3.
Proc Natl Acad Sci U S A ; 121(23): e2407437121, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38814864

RESUMO

The accessory protease transmembrane protease serine 2 (TMPRSS2) enhances severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uptake into ACE2-expressing cells, although how increased entry impacts downstream viral and host processes remains unclear. To investigate this in more detail, we performed infection assays in engineered cells promoting ACE2-mediated entry with and without TMPRSS2 coexpression. Electron microscopy and inhibitor experiments indicated TMPRSS2-mediated cell entry was associated with increased virion internalization into endosomes, and partially dependent upon clathrin-mediated endocytosis. TMPRSS2 increased panvariant uptake efficiency and enhanced early rates of virus replication, transcription, and secretion, with variant-specific profiles observed. On the host side, transcriptional profiling confirmed the magnitude of infection-induced antiviral and proinflammatory responses were linked to uptake efficiency, with TMPRSS2-assisted entry boosting early antiviral responses. In addition, TMPRSS2-enhanced infections increased rates of cytopathology, apoptosis, and necrosis and modulated virus secretion kinetics in a variant-specific manner. On the virus side, convergent signatures of cell-uptake-dependent innate immune induction were recorded in viral genomes, manifesting as switches in dominant coupled Nsp3 residues whose frequencies were correlated to the magnitude of the cellular response to infection. Experimentally, we demonstrated that selected Nsp3 mutations conferred enhanced interferon antagonism. More broadly, we show that TMPRSS2 orthologues from evolutionarily diverse mammals facilitate panvariant enhancement of cell uptake. In summary, our study uncovers previously unreported associations, linking cell entry efficiency to innate immune activation kinetics, cell death rates, virus secretion dynamics, and convergent selection of viral mutations. These data expand our understanding of TMPRSS2's role in the SARS-CoV-2 life cycle and confirm its broader significance in zoonotic reservoirs and animal models.


Assuntos
COVID-19 , Imunidade Inata , SARS-CoV-2 , Serina Endopeptidases , Internalização do Vírus , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , SARS-CoV-2/metabolismo , Humanos , Serina Endopeptidases/metabolismo , Serina Endopeptidases/genética , COVID-19/virologia , COVID-19/imunologia , COVID-19/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/genética , Replicação Viral , Animais , Endocitose , Células HEK293 , Chlorocebus aethiops , Citologia
4.
N Engl J Med ; 389(1): 22-32, 2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37345876

RESUMO

BACKGROUND: Coinfection with hepatitis D virus (HDV) accelerates the progression of liver disease associated with chronic hepatitis B. Bulevirtide inhibits the entry of HDV into hepatocytes. METHODS: In this ongoing phase 3 trial, patients with chronic hepatitis D, with or without compensated cirrhosis, were randomly assigned, in a 1:1:1 ratio, to receive bulevirtide subcutaneously at 2 mg per day (2-mg group) or 10 mg per day (10-mg group) for 144 weeks or to receive no treatment for 48 weeks followed by bulevirtide subcutaneously at 10 mg per day for 96 weeks (control group). Patients will complete 96 weeks of additional follow-up after the end of treatment. The primary end point was a combined response at week 48 of an undetectable HDV RNA level, or a level that decreased by at least 2 log10 IU per milliliter from baseline, and normalization of the alanine aminotransferase (ALT) level. The key secondary end point was an undetectable HDV RNA level at week 48, in a comparison between the 2-mg group and the 10-mg group. RESULTS: A total of 49 patients were assigned to the 2-mg group, 50 to the 10-mg group, and 51 to the control group. A primary end-point response occurred in 45% of patients in the 2-mg group, 48% in the 10-mg group, and 2% in the control group (P<0.001 for the comparison of each dose group with the control group). The HDV RNA level at week 48 was undetectable in 12% of patients in the 2-mg group and in 20% in the 10-mg group (P = 0.41). The ALT level normalized in 12% of patients in the control group, 51% in the 2-mg group (difference from control, 39 percentage points [95% confidence interval {CI}, 20 to 56]), and 56% in the 10-mg group (difference from control, 44 percentage points [95% CI, 26 to 60]). Loss of hepatitis B virus surface antigen (HBsAg) or an HBsAg level that decreased by at least 1 log10 IU per milliliter did not occur in the bulevirtide groups by week 48. Headache, pruritus, fatigue, eosinophilia, injection-site reactions, upper abdominal pain, arthralgia, and asthenia were more common in the 2-mg and 10-mg groups combined than in the control group. No treatment-related serious adverse events occurred. Dose-dependent increases in bile acid levels were noted in the 2-mg and 10-mg groups. CONCLUSIONS: After 48 weeks of bulevirtide treatment, HDV RNA and ALT levels were reduced in patients with chronic hepatitis D. (Funded by Gilead Sciences; MYR 301 ClinicalTrials.gov number, NCT03852719.).


Assuntos
Antivirais , Hepatite B Crônica , Hepatite D Crônica , Humanos , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , Hepatite D Crônica/tratamento farmacológico , Vírus Delta da Hepatite/genética , RNA , Coinfecção/tratamento farmacológico , Coinfecção/virologia
5.
Nature ; 583(7816): 469-472, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32408336

RESUMO

A new coronavirus was recently discovered and named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Infection with SARS-CoV-2 in humans causes coronavirus disease 2019 (COVID-19) and has been rapidly spreading around the globe1,2. SARS-CoV-2 shows some similarities to other coronaviruses; however, treatment options and an understanding of how SARS-CoV-2 infects cells are lacking. Here we identify the host cell pathways that are modulated by SARS-CoV-2 and show that inhibition of these pathways prevents viral replication in human cells. We established a human cell-culture model for infection with a clinical isolate of SARS-CoV-2. Using this cell-culture system, we determined the infection profile of SARS-CoV-2 by translatome3 and proteome proteomics at different times after infection. These analyses revealed that SARS-CoV-2 reshapes central cellular pathways such as translation, splicing, carbon metabolism, protein homeostasis (proteostasis) and nucleic acid metabolism. Small-molecule inhibitors that target these pathways prevented viral replication in cells. Our results reveal the cellular infection profile of SARS-CoV-2 and have enabled the identification of drugs that inhibit viral replication. We anticipate that our results will guide efforts to understand the molecular mechanisms that underlie the modulation of host cells after infection with SARS-CoV-2. Furthermore, our findings provide insights for the development of therapies for the treatment of COVID-19.


Assuntos
Betacoronavirus/efeitos dos fármacos , Betacoronavirus/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/metabolismo , Terapia de Alvo Molecular , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/metabolismo , Proteômica , Betacoronavirus/genética , Betacoronavirus/crescimento & desenvolvimento , COVID-19 , Células CACO-2 , Carbono/metabolismo , Infecções por Coronavirus/genética , Infecções por Coronavirus/virologia , Avaliação Pré-Clínica de Medicamentos , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , Técnicas In Vitro , Cinética , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/virologia , Biossíntese de Proteínas/efeitos dos fármacos , Proteoma/metabolismo , Proteostase , Splicing de RNA , SARS-CoV-2 , Fatores de Tempo , Replicação Viral/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
6.
Nature ; 587(7835): 657-662, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32726803

RESUMO

The papain-like protease PLpro is an essential coronavirus enzyme that is required for processing viral polyproteins to generate a functional replicase complex and enable viral spread1,2. PLpro is also implicated in cleaving proteinaceous post-translational modifications on host proteins as an evasion mechanism against host antiviral immune responses3-5. Here we perform biochemical, structural and functional characterization of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PLpro (SCoV2-PLpro) and outline differences with SARS-CoV PLpro (SCoV-PLpro) in regulation of host interferon and NF-κB pathways. SCoV2-PLpro and SCoV-PLpro share 83% sequence identity but exhibit different host substrate preferences; SCoV2-PLpro preferentially cleaves the ubiquitin-like interferon-stimulated gene 15 protein (ISG15), whereas SCoV-PLpro predominantly targets ubiquitin chains. The crystal structure of SCoV2-PLpro in complex with ISG15 reveals distinctive interactions with the amino-terminal ubiquitin-like domain of ISG15, highlighting the high affinity and specificity of these interactions. Furthermore, upon infection, SCoV2-PLpro contributes to the cleavage of ISG15 from interferon responsive factor 3 (IRF3) and attenuates type I interferon responses. Notably, inhibition of SCoV2-PLpro with GRL-0617 impairs the virus-induced cytopathogenic effect, maintains the antiviral interferon pathway and reduces viral replication in infected cells. These results highlight a potential dual therapeutic strategy in which targeting of SCoV2-PLpro can suppress SARS-CoV-2 infection and promote antiviral immunity.


Assuntos
COVID-19/imunologia , COVID-19/virologia , Proteases Semelhantes à Papaína de Coronavírus/química , Proteases Semelhantes à Papaína de Coronavírus/metabolismo , Imunidade Inata , SARS-CoV-2/enzimologia , SARS-CoV-2/imunologia , Animais , Proteases Semelhantes à Papaína de Coronavírus/antagonistas & inibidores , Citocinas/química , Citocinas/metabolismo , Enzimas Desubiquitinantes/antagonistas & inibidores , Enzimas Desubiquitinantes/química , Enzimas Desubiquitinantes/metabolismo , Humanos , Fator Regulador 3 de Interferon/metabolismo , Interferons/imunologia , Interferons/metabolismo , Camundongos , Modelos Moleculares , Simulação de Dinâmica Molecular , NF-kappa B/imunologia , NF-kappa B/metabolismo , Ligação Proteica , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Ubiquitinação , Ubiquitinas/química , Ubiquitinas/metabolismo , Tratamento Farmacológico da COVID-19
7.
PLoS Biol ; 20(11): e3001871, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36383605

RESUMO

Epidemiological data demonstrate that Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) Alpha and Delta are more transmissible, infectious, and pathogenic than previous variants. Phenotypic properties of VOC remain understudied. Here, we provide an extensive functional study of VOC Alpha replication and cell entry phenotypes assisted by reverse genetics, mutational mapping of spike in lentiviral pseudotypes, viral and cellular gene expression studies, and infectivity stability assays in an enhanced range of cell and epithelial culture models. In almost all models, VOC Alpha spread less or equally efficiently as ancestral (B.1) SARS-CoV-2. B.1. and VOC Alpha shared similar susceptibility to serum neutralization. Despite increased relative abundance of specific sgRNAs in the context of VOC Alpha infection, immune gene expression in infected cells did not differ between VOC Alpha and B.1. However, inferior spreading and entry efficiencies of VOC Alpha corresponded to lower abundance of proteolytically cleaved spike products presumably linked to the T716I mutation. In addition, we identified a bronchial cell line, NCI-H1299, which supported 24-fold increased growth of VOC Alpha and is to our knowledge the only cell line to recapitulate the fitness advantage of VOC Alpha compared to B.1. Interestingly, also VOC Delta showed a strong (595-fold) fitness advantage over B.1 in these cells. Comparative analysis of chimeric viruses expressing VOC Alpha spike in the backbone of B.1, and vice versa, showed that the specific replication phenotype of VOC Alpha in NCI-H1299 cells is largely determined by its spike protein. Despite undetectable ACE2 protein expression in NCI-H1299 cells, CRISPR/Cas9 knock-out and antibody-mediated blocking experiments revealed that multicycle spread of B.1 and VOC Alpha required ACE2 expression. Interestingly, entry of VOC Alpha, as opposed to B.1 virions, was largely unaffected by treatment with exogenous trypsin or saliva prior to infection, suggesting enhanced resistance of VOC Alpha spike to premature proteolytic cleavage in the extracellular environment of the human respiratory tract. This property may result in delayed degradation of VOC Alpha particle infectivity in conditions typical of mucosal fluids of the upper respiratory tract that may be recapitulated in NCI-H1299 cells closer than in highly ACE2-expressing cell lines and models. Our study highlights the importance of cell model evaluation and comparison for in-depth characterization of virus variant-specific phenotypes and uncovers a fine-tuned interrelationship between VOC Alpha- and host cell-specific determinants that may underlie the increased and prolonged virus shedding detected in patients infected with VOC Alpha.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Enzima de Conversão de Angiotensina 2/genética , Eliminação de Partículas Virais , Anticorpos Bloqueadores
8.
Mol Cell Proteomics ; 22(5): 100537, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37001587

RESUMO

The ancestral SARS-CoV-2 strain that initiated the Covid-19 pandemic at the end of 2019 has rapidly mutated into multiple variants of concern with variable pathogenicity and increasing immune escape strategies. However, differences in host cellular antiviral responses upon infection with SARS-CoV-2 variants remain elusive. Leveraging whole-cell proteomics, we determined host signaling pathways that are differentially modulated upon infection with the clinical isolates of the ancestral SARS-CoV-2 B.1 and the variants of concern Delta and Omicron BA.1. Our findings illustrate alterations in the global host proteome landscape upon infection with SARS-CoV-2 variants and the resulting host immune responses. Additionally, viral proteome kinetics reveal declining levels of viral protein expression during Omicron BA.1 infection when compared to ancestral B.1 and Delta variants, consistent with its reduced replication rates. Moreover, molecular assays reveal deferral activation of specific host antiviral signaling upon Omicron BA.1 and BA.2 infections. Our study provides an overview of host proteome profile of multiple SARS-CoV-2 variants and brings forth a better understanding of the instigation of key immune signaling pathways causative for the differential pathogenicity of SARS-CoV-2 variants.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Proteoma , Pandemias , Antivirais , Anticorpos Neutralizantes
9.
J Hepatol ; 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38734383

RESUMO

BACKGROUND & AIMS: Bulevirtide (BLV), a first-in-class entry inhibitor, is approved in Europe for the treatment of chronic hepatitis delta (CHD). BLV monotherapy was superior to delayed treatment at week (W) 48, the primary efficacy endpoint, in the MYR301 study (NCT03852719). Here, we assessed if continued BLV therapy until W96 would improve virologic and biochemical response rates, particularly among patients who did not achieve virologic response at W24. METHODS: In this ongoing, open-label, randomized phase III study, patients with CHD (N = 150) were randomized (1:1:1) to treatment with BLV 2 mg/day (n = 49) or 10 mg/day (n = 50), each for 144 weeks, or to delayed treatment for 48 weeks followed by BLV 10 mg/day for 96 weeks (n = 51). Combined response was defined as undetectable hepatitis delta virus (HDV) RNA or a decrease in HDV RNA by ≥2 log10 IU/ml from baseline and alanine aminotransferase (ALT) normalization. Other endpoints included virologic response, ALT normalization, and change in HDV RNA. RESULTS: Of 150 patients, 143 (95%) completed 96 weeks of the study. Efficacy responses were maintained and/or improved between W48 and W96, with similar combined, virologic, and biochemical response rates between BLV 2 and 10 mg. Of the patients with a suboptimal early virologic response at W24, 43% of non-responders and 82% of partial responders achieved virologic response at W96. Biochemical improvement often occurred independently of virologic response. Adverse events were mostly mild, with no serious adverse events related to BLV. CONCLUSIONS: Virologic and biochemical responses were maintained and/or increased with longer term BLV therapy, including in those with suboptimal early virologic response. BLV monotherapy for CHD was safe and well tolerated through W96. IMPACT AND IMPLICATIONS: In July 2023, bulevirtide was fully approved for the treatment of chronic hepatitis delta (CHD) in Europe based on clinical study results from up to 48 weeks of treatment. Understanding the efficacy and safety of bulevirtide over the longer term is important for healthcare providers. In this analysis, we demonstrate that bulevirtide monotherapy for 96 weeks in patients with CHD was associated with continued improvements in combined, virologic, and biochemical responses as well as liver stiffness from week 48 at both the 2 mg and 10 mg doses. Patients with suboptimal virologic responses to bulevirtide at week 24 also benefited from continued therapy, with the majority achieving virologic response or biochemical improvement by week 96. GOV IDENTIFIER: NCT03852719.

10.
J Med Virol ; 96(1): e29354, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38180134

RESUMO

The Mpox virus can cause severe disease in the susceptible population with dermatologic and systemic manifestations. Furthermore, ophthalmic manifestations of mpox infection are well documented. Topical trifluridine (TFT) eye drops have been used for therapy of ophthalmic mpox infection in patients, however, its efficacy against mpox virus infection in this scenario has not been previously shown. In the present study, we have established ophthalmic cell models suitable for the infection with mpox virus. We show, that TFT is effective against a broad range of mpox isolates in conjunctival epithelial cells and keratocytes. Further, TFT remained effective against a tecovirimat-resistant virus strain. In the context of drug combinations, a nearly additive effect was observed for TFT combinations with brincidofovir and tecovirimat in conjunctival epithelial cells, while a slight antagonism was observed for both combinations in keratocytes. Altogether, our findings demonstrate TFT as a promising drug for treatment of ophthalmic mpox infection able to overcome tecovirimat resistance. However, conflicting results regarding the effect of drug combinations with approved compounds warrant close monitoring of such use in patients.


Assuntos
Mpox , Trifluridina , Humanos , Trifluridina/farmacologia , Trifluridina/uso terapêutico , Olho , Combinação de Medicamentos , Benzamidas , Isoindóis , Monkeypox virus
11.
Support Care Cancer ; 32(4): 221, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467829

RESUMO

BACKGROUND: Vaccination against SARS-CoV-2 is recommended for cancer patients. However, long-term data on the effectiveness in the pediatric setting are lacking. METHODS: Pediatric patients < 18 years on active treatment for cancer and without prior SARS-CoV-2 infection received three doses of an mRNA vaccine. The clinical course and humoral and cellular immunity were evaluated at the end of the follow-up period of ≥ 1 year after the third dose of vaccine. RESULTS: SARS-CoV-2 infection occurred in 17 of 19 analyzed patients (median age 16.5 years) during the follow-up period (median 17 months), but no severe symptoms were seen. At ≥ 1 year after the last SARS-CoV-2 antigen exposure, 4 of 17 patients had received the recommended booster vaccine. At the end of the follow-up period, all evaluable 15 patients had anti-SARS-CoV-2 receptor-binding domain IgG antibodies. Twelve of the 15 patients had neutralizing antibody titers ≥ 1:10 against the Delta variant and 12/15 and 13/15 against the BA.1 and BA.5 variants, respectively. Specific T cells against SARS-CoV-2 antigens were seen in 9/13 patients. CONCLUSIONS: Most SARS-CoV-2-vaccinated pediatric cancer patients had SARS-CoV-2 infections and limited interest in booster vaccination. At 1 year after the last antigen exposure, which was mostly an infection, humoral immune responses remained strong. TRIAL REGISTRATION: German Clinical Trials Register DRKS00025254, May 26, 2021.


Assuntos
COVID-19 , Neoplasias , Vacinas , Humanos , Criança , Adolescente , SARS-CoV-2 , COVID-19/prevenção & controle , Seguimentos , Anticorpos Antivirais , Neoplasias/terapia , Vacinação
12.
Gut ; 72(6): 1186-1195, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-35977815

RESUMO

OBJECTIVE: Chronic HBV/HDV infections are a major cause of liver cancer. Current treatments can only rarely eliminate HBV and HDV. Our previously developed preS1-HDAg immunotherapy could induce neutralising antibodies to HBV in vivo and raise HBV/HDV-specific T-cells. Here, we further investigate if a heterologous prime-boost strategy can circumvent T-cell tolerance and preclude HDV superinfection in vivo. DESIGN: A DNA prime-protein boost strategy was evaluated for immunogenicity in mice and rabbits. Its ability to circumvent T-cell tolerance was assessed in immunocompetent hepatitis B surface antigen (HBsAg)-transgenic mice. Neutralisation of HBV and HDV was evaluated both in vitro and in immunodeficient human-liver chimeric mice upon adoptive transfer. RESULTS: The prime-boost strategy elicits robust HBV/HDV-specific T-cells and preS1-antibodies that can effectively prevent HBV and HDV (co-)infection in vitro and in vivo. In a mouse model representing the chronic HBsAg carrier state, active immunisation primes high levels of preS1-antibodies and HDAg-specific T-cells. Moreover, transfer of vaccine-induced antibodies completely protects HBV-infected human-liver chimeric mice from HDV superinfection. CONCLUSION: The herein described preS1-HDAg immunotherapy is shown to be immunogenic and vaccine-induced antibodies are highly effective at preventing HBV and HDV (super)infection both in vitro and in vivo. Our vaccine can complement current and future therapies for the control of chronic HBV and HDV infection.


Assuntos
Hepatite B Crônica , Hepatite B , Superinfecção , Humanos , Camundongos , Animais , Coelhos , Antígenos da Hepatite delta , Antígenos de Superfície da Hepatite B , Hepatite B Crônica/prevenção & controle , Superinfecção/prevenção & controle , Vírus Delta da Hepatite/genética , Hepatite B/prevenção & controle , Vírus da Hepatite B/genética , Anticorpos Antivirais , Camundongos Transgênicos
13.
Am J Physiol Cell Physiol ; 325(1): C129-C140, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37273239

RESUMO

Liver cirrhosis is the end stage of all chronic liver diseases and contributes significantly to overall mortality of 2% globally. The age-standardized mortality from liver cirrhosis in Europe is between 10 and 20% and can be explained by not only the development of liver cancer but also the acute deterioration in the patient's overall condition. The development of complications including accumulation of fluid in the abdomen (ascites), bleeding in the gastrointestinal tract (variceal bleeding), bacterial infections, or a decrease in brain function (hepatic encephalopathy) define an acute decompensation that requires therapy and often leads to acute-on-chronic liver failure (ACLF) by different precipitating events. However, due to its complexity and organ-spanning nature, the pathogenesis of ACLF is poorly understood, and the common underlying mechanisms leading to the development of organ dysfunction or failure in ACLF are still elusive. Apart from general intensive care interventions, there are no specific therapy options for ACLF. Liver transplantation is often not possible in these patients due to contraindications and a lack of prioritization. In this review, we describe the framework of the ACLF-I project consortium funded by the Hessian Ministry of Higher Education, Research and the Arts (HMWK) based on existing findings and will provide answers to these open questions.


Assuntos
Insuficiência Hepática Crônica Agudizada , Doença Hepática Terminal , Varizes Esofágicas e Gástricas , Humanos , Doença Hepática Terminal/complicações , Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/complicações , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Insuficiência Hepática Crônica Agudizada/terapia , Insuficiência Hepática Crônica Agudizada/etiologia
14.
Clin Infect Dis ; 76(3): e510-e513, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35901198

RESUMO

Our study in 21 pediatric cancer patients demonstrates that 3 doses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger RNA vaccine (BioNTech/Pfizer) elicited both humoral and cellular immunity in most patients during chemotherapy. Immunity was stronger in children with solid tumors and during maintenance therapy compared to those with hematological malignancies or during intensive chemotherapy. Clinical Trials Registration.ȃGerman Registry for Clinical Trials (DRKS00025254).


Assuntos
COVID-19 , Neoplasias , Criança , Humanos , Anticorpos Antivirais , COVID-19/prevenção & controle , Imunidade Celular , Vacinas de mRNA , Neoplasias/tratamento farmacológico , RNA Mensageiro , SARS-CoV-2 , Vacinação
15.
Eur J Immunol ; 52(7): 1194-1197, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35389515

RESUMO

Little is known about the cellular immune response to SARS-CoV-2 vaccination in patients after HSCT and B-NHL with iatrogenic B-cell aplasia. In nonseroconverted HSCT patients, induction of specific T-cell responses was assessed. The majority of allogeneic HSCT patients not showing humoral responses to vaccination also fail to mount antigen-specific T-cell responses.


Assuntos
COVID-19 , Transplante de Células-Tronco Hematopoéticas , Anticorpos Antivirais , Vacinas contra COVID-19 , Humanos , Imunidade Celular , Imunidade Humoral , SARS-CoV-2 , Linfócitos T , Vacinação
16.
Eur J Immunol ; 52(5): 770-783, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34355795

RESUMO

TRIANNI mice carry an entire set of human immunoglobulin V region gene segments and are a powerful tool to rapidly isolate human monoclonal antibodies. After immunizing these mice with DNA encoding the spike protein of SARS-CoV-2 and boosting with spike protein, we identified 29 hybridoma antibodies that reacted with the SARS-CoV-2 spike protein. Nine antibodies neutralize SARS-CoV-2 infection at IC50 values in the subnanomolar range. ELISA-binding studies and DNA sequence analyses revealed one cluster of three clonally related neutralizing antibodies that target the receptor-binding domain and compete with the cellular receptor hACE2. A second cluster of six clonally related neutralizing antibodies bind to the N-terminal domain of the spike protein without competing with the binding of hACE2 or cluster 1 antibodies. SARS-CoV-2 mutants selected for resistance to an antibody from one cluster are still neutralized by an antibody from the other cluster. Antibodies from both clusters markedly reduced viral spread in mice transgenic for human ACE2 and protected the animals from SARS-CoV-2-induced weight loss. The two clusters of potent noncompeting SARS-CoV-2 neutralizing antibodies provide potential candidates for therapy and prophylaxis of COVID-19. The study further supports transgenic animals with a human immunoglobulin gene repertoire as a powerful platform in pandemic preparedness initiatives.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais , Humanos , Camundongos , SARS-CoV-2
17.
J Med Virol ; 95(3): e28686, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36938992

RESUMO

Recent findings in permanent cell lines suggested that SARS-CoV-2 Omicron BA.1 induces a stronger interferon response than Delta. Here, we show that BA.1 and BA.5 but not Delta induce an antiviral state in air-liquid interface cultures of primary human bronchial epithelial cells and primary human monocytes. Both Omicron subvariants caused the production of biologically active types I (α/ß) and III (λ) interferons and protected cells from super-infection with influenza A viruses. Notably, abortive Omicron infection of monocytes was sufficient to protect monocytes from influenza A virus infection. Interestingly, while influenza-like illnesses surged during the Delta wave in England, their spread rapidly declined upon the emergence of Omicron. Mechanistically, Omicron-induced interferon signaling was mediated via double-stranded RNA recognition by MDA5, as MDA5 knockout prevented it. The JAK/STAT inhibitor baricitinib inhibited the Omicron-mediated antiviral response, suggesting it is caused by MDA5-mediated interferon production, which activates interferon receptors that then trigger JAK/STAT signaling. In conclusion, our study (1) demonstrates that only Omicron but not Delta induces a substantial interferon response in physiologically relevant models, (2) shows that Omicron infection protects cells from influenza A virus super-infection, and (3) indicates that BA.1 and BA.5 induce comparable antiviral states.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Humana , Inibidores de Janus Quinases , Humanos , SARS-CoV-2 , Interferons , Antivirais
18.
J Med Virol ; 95(3): e28652, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36897017

RESUMO

The antiviral drugs tecovirimat, brincidofovir, and cidofovir are considered for mpox (monkeypox) treatment despite a lack of clinical evidence. Moreover, their use is affected by toxic side-effects (brincidofovir, cidofovir), limited availability (tecovirimat), and potentially by resistance formation. Hence, additional, readily available drugs are needed. Here, therapeutic concentrations of nitroxoline, a hydroxyquinoline antibiotic with a favourable safety profile in humans, inhibited the replication of 12 mpox virus isolates from the current outbreak in primary cultures of human keratinocytes and fibroblasts and a skin explant model by interference with host cell signalling. Tecovirimat, but not nitroxoline, treatment resulted in rapid resistance development. Nitroxoline remained effective against the tecovirimat-resistant strain and increased the anti-mpox virus activity of tecovirimat and brincidofovir. Moreover, nitroxoline inhibited bacterial and viral pathogens that are often co-transmitted with mpox. In conclusion, nitroxoline is a repurposing candidate for the treatment of mpox due to both antiviral and antimicrobial activity.


Assuntos
Reposicionamento de Medicamentos , Mpox , Nitroquinolinas , Humanos , Antibacterianos/farmacologia , Antivirais/farmacologia , Cidofovir , Mpox/tratamento farmacológico , Nitroquinolinas/farmacologia
19.
Infection ; 51(4): 805-811, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37129842

RESUMO

The SARS-CoV-2 pandemic has highlighted the importance of viable infection surveillance and the relevant infrastructure. From a German perspective, an integral part of this infrastructure, genomic pathogen sequencing, was at best fragmentary and stretched to its limits due to the lack or inefficient use of equipment, human resources, data management and coordination. The experience in other countries has shown that the rate of sequenced positive samples and linkage of genomic and epidemiological data (person, place, time) represent important factors for a successful application of genomic pathogen surveillance. Planning, establishing and consistently supporting adequate structures for genomic pathogen surveillance will be crucial to identify and combat future pandemics as well as other challenges in infectious diseases such as multi-drug resistant bacteria and healthcare-associated infections. Therefore, the authors propose a multifaceted and coordinated process for the definition of procedural, legal and technical standards for comprehensive genomic pathogen surveillance in Germany, covering the areas of genomic sequencing, data collection and data linkage, as well as target pathogens. A comparative analysis of the structures established in Germany and in other countries is applied. This proposal aims to better tackle epi- and pandemics to come and take action from the "lessons learned" from the SARS-CoV-2 pandemic.


Assuntos
COVID-19 , Infecção Hospitalar , Humanos , Pandemias/prevenção & controle , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2/genética , Genômica
20.
Artigo em Alemão | MEDLINE | ID: mdl-36811648

RESUMO

The SARS-CoV­2 pandemic has shown a deficit of essential epidemiological infrastructure, especially with regard to genomic pathogen surveillance in Germany. In order to prepare for future pandemics, the authors consider it urgently necessary to remedy this existing deficit by establishing an efficient infrastructure for genomic pathogen surveillance. Such a network can build on structures, processes, and interactions that have already been initiated regionally and further optimize them. It will be able to respond to current and future challenges with a high degree of adaptability.The aim of this paper is to address the urgency and to outline proposed measures for establishing an efficient, adaptable, and responsive genomic pathogen surveillance network, taking into account external framework conditions and internal standards. The proposed measures are based on global and country-specific best practices and strategy papers. Specific next steps to achieve an integrated genomic pathogen surveillance include linking epidemiological data with pathogen genomic data; sharing and coordinating existing resources; making surveillance data available to relevant decision-makers, the public health service, and the scientific community; and engaging all stakeholders. The establishment of a genomic pathogen surveillance network is essential for the continuous, stable, active surveillance of the infection situation in Germany, both during pandemic phases and beyond.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Alemanha/epidemiologia , Genômica
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