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1.
Nat Commun ; 12(1): 1153, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608536

RESUMO

Zaire ebolavirus (EBOV) is a highly pathogenic filovirus which can result in Ebola virus disease (EVD); a serious medical condition that presents as flu like symptoms but then often leads to more serious or fatal outcomes. The 2013-16 West Africa epidemic saw an unparalleled number of cases. Here we show characterisation and identification of T cell epitopes in surviving patients from Guinea to the EBOV glycoprotein. We perform interferon gamma (IFNγ) ELISpot using a glycoprotein peptide library to identify T cell epitopes and determine the CD4+ or CD8+ T cell component response. Additionally, we generate data on the T cell phenotype and measure polyfunctional cytokine secretion by these antigen specific cells. We show candidate peptides able to elicit a T cell response in EBOV survivors and provide inferred human leukocyte antigen (HLA) allele restriction. This data informs on the long-term T cell response to Ebola virus disease and highlights potentially important immunodominant peptides.


Assuntos
Ebolavirus/imunologia , Epitopos de Linfócito T/imunologia , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/imunologia , Linfócitos T/imunologia , África Ocidental/epidemiologia , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos , Ebolavirus/genética , ELISPOT , Epidemias , Glicoproteínas/genética , Doença pelo Vírus Ebola/epidemiologia , Humanos , Imunidade Celular , Interferon gama , Sobreviventes
3.
Nature ; 590(7846): 468-472, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33505020

RESUMO

Neutralizing antibody function provides a foundation for the efficacy of vaccines and therapies1-3. Here, using a robust in vitro Ebola virus (EBOV) pseudo-particle infection assay and a well-defined set of solid-phase assays, we describe a wide spectrum of antibody responses in a cohort of healthy survivors of the Sierra Leone EBOV outbreak of 2013-2016. Pseudo-particle virus-neutralizing antibodies correlated with total anti-EBOV reactivity and neutralizing antibodies against live EBOV. Variant EBOV glycoproteins (1995 and 2014 strains) were similarly neutralized. During longitudinal follow-up, antibody responses fluctuated in a 'decay-stimulation-decay' pattern that suggests de novo restimulation by EBOV antigens after recovery. A pharmacodynamic model of antibody reactivity identified a decay half-life of 77-100 days and a doubling time of 46-86 days in a high proportion of survivors. The highest antibody reactivity was observed around 200 days after an individual had recovered. The model suggests that EBOV antibody reactivity declines over 0.5-2 years after recovery. In a high proportion of healthy survivors, antibody responses undergo rapid restimulation. Vigilant follow-up of survivors and possible elective de novo antigenic stimulation by vaccine immunization should be considered in order to prevent EBOV viral recrudescence in recovering individuals and thereby to mitigate the potential risk of reseeding an outbreak.


Assuntos
Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Convalescença , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Sobreviventes , Adolescente , Adulto , África Ocidental/epidemiologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Estudos de Coortes , Feminino , Meia-Vida , Doença pelo Vírus Ebola/sangue , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização , Fatores de Tempo , Viremia/sangue , Viremia/imunologia , Adulto Jovem
5.
PLoS Negl Trop Dis ; 14(9): e0008602, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32886656

RESUMO

Besides the common Fc receptor (FcR)-mediated mechanism of antibody-dependent enhancement (ADE), Ebola virus (EBOV) is known to utilize the complement component C1q for ADE of infection. This mechanism is FcR-independent and mediated by cross-linking of virus-antibody-C1q complexes to cell surface C1q receptors, leading to enhanced viral entry into cells. Using confocal microscopy, we found that virus-like particles (VLPs) consisting of EBOV glycoprotein, nucleoprotein, and matrix protein attached to the surface of human kidney 293 cells more efficiently in the presence of an ADE monoclonal antibody and C1q than with the antibody or C1q alone, and that there was no significant difference in the efficiency of VLP uptake into endosomes between the C1q-mediated ADE and non-ADE entry. Accordingly, both ADE and non-ADE infection were similarly decreased by inhibitors of the signaling pathways known to be required for endocytosis. These results suggest that C1q-mediated ADE of EBOV infection is simply caused by increased attachment of virus particles to the cell surface, which is distinct from the mechanism of FcR-mediated ADE requiring intracellular signaling to promote phagocytosis/macropinocytosis.


Assuntos
Anticorpos Facilitadores/imunologia , Complemento C1q/metabolismo , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Glicoproteínas de Membrana/metabolismo , Receptores de Complemento/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Linhagem Celular , Chlorocebus aethiops , Ebolavirus/patogenicidade , Endocitose/imunologia , Células HEK293 , Doença pelo Vírus Ebola/patologia , Humanos , Células Vero , Proteínas Virais/imunologia , Proteínas Virais/metabolismo , Ligação Viral
6.
PLoS One ; 15(8): e0238196, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841291

RESUMO

The need for an efficacious vaccine against highly pathogenic filoviruses was reinforced by the devastating 2014-2016 outbreak of Ebola virus (EBOV) disease (EVD) in Guinea, Sierra Leone, and Liberia that resulted in over 28,000 cases and over 11,300 deaths. In addition, the 2018-2020 outbreak in the Democratic Republic of the Congo currently has over 3,400 cases and over 2,200 deaths. A fully licensed vaccine and at least one other investigational vaccine are being deployed to combat this EVD outbreak. To support vaccine development and pre-clinical/clinical testing a Filovirus Animal Nonclinical Group (FANG) human anti-EBOV GP IgG ELISA was developed to measure anti-EBOV GP IgG antibodies. This ELISA is currently being used in multiple laboratories. Reported here is a characterization of an interlaboratory statistical analysis of the human anti-EBOV GP IgG ELISA as part of a collaborative study between five participating laboratories. Each laboratory used similar method protocols and reagents to measure anti-EBOV GP IgG levels in human serum samples from a proficiency panel consisting of ten serum samples created by the differential dilution of a serum sample positive for anti-GP IgG antibodies (BMIZAIRE105) with negative serum (BMI529). The total assay variability (inter- and intra-assay variability) %CVs observed at each laboratory ranged from 12.2 to 30.6. Intermediate precision (inter-assay variability) for the laboratory runs ranged from 8.9 to 21.7%CV and repeatability (intra-assay variability) %CVs ranged from 7.2 to 23.7. The estimated slope for the relationship between log10(Target Concentration) and the log10(Observed Concentration) across all five laboratories was 0.95 with a 90% confidence interval of (0.93, 0.97). Equivalence test results showed that the 90% confidence interval for the ratios for the sample-specific mean concentrations at the five individual labs to the overall laboratory consensus value were within the equivalence bounds of 0.80 to 1.25 for each laboratory and test sample, except for six test samples from Lab D, two samples from Lab B1, and one sample from Lab B2. The mean laboratory concentrations for Lab D were less than those from the other laboratories by 20% on average across the serum samples. The evaluation of the proficiency panel at these laboratories provides a limited assessment of assay precision (intermediate precision, repeatability, and total assay variability), dilutional linearity, and accuracy. This evaluation suggests that the within-laboratory performance of the anti-EBOV GP IgG ELISA as implemented at the five laboratories is consistent with the intended use of the assay based on the acceptance criteria used by laboratories that have validated the assay. However, the assessment of between-laboratory performance revealed lower observed concentrations at Lab D and greater variability in assay results at Lab B1 relative to other laboratories.


Assuntos
Anticorpos Antivirais/sangue , Ebolavirus/imunologia , Ensaio de Imunoadsorção Enzimática/normas , Doença pelo Vírus Ebola/imunologia , Proteínas Virais/imunologia , África Ocidental/epidemiologia , Animais , República Democrática do Congo/epidemiologia , Surtos de Doenças , Vacinas contra Ebola/imunologia , Vacinas contra Ebola/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/estatística & dados numéricos , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Imunoglobulina G/sangue , Laboratórios , Variações Dependentes do Observador
7.
BMC Infect Dis ; 20(1): 461, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32611400

RESUMO

BACKGROUND: Uganda has experienced seven Ebola Virus Disease (EVD) outbreaks and four Marburg Virus Disease (MVD) outbreaks between 2000 and 2019. We investigated the seroprevalence and risk factors for Marburg virus and ebolaviruses in gold mining communities around Kitaka gold mine in Western Uganda and compared them to non-mining communities in Central Uganda. METHODS: A questionnaire was administered and human blood samples were collected from three exposure groups in Western Uganda (gold miners, household members of miners, non-miners living within 50 km of Kitaka mine). The unexposed controls group sampled was community members in Central Uganda far away from any gold mining activity which we considered as low-risk for filovirus infection. ELISA serology was used to analyse samples, detecting IgG antibodies against Marburg virus and ebolaviruses (filoviruses). Data were analysed in STATA software using risk ratios and odds ratios. RESULTS: Miners in western Uganda were 5.4 times more likely to be filovirus seropositive compared to the control group in central Uganda (RR = 5.4; 95% CI 1.5-19.7) whereas people living in high-risk areas in Ibanda and Kamwenge districts were 3.6 more likely to be seropositive compared to control group in Luweeero district (RR = 3.6; 95% CI 1.1-12.2). Among all participants, filovirus seropositivity was 2.6% (19/724) of which 2.3% (17/724) were reactive to Sudan virus only and 0.1% (1/724) to Marburg virus. One individual seropositive for Sudan virus also had IgG antibodies reactive to Bundibugyo virus. The risk factors for filovirus seropositivity identified included mining (AOR = 3.4; 95% CI 1.3-8.5), male sex (AOR = 3.1; 95% CI 1.01-9.5), going inside mines (AOR = 3.1; 95% CI 1.2-8.2), cleaning corpses (AOR = 3.1; 95% CI 1.04-9.1) and contact with suspect filovirus cases (AOR = 3.9, 95% CI 1.04-14.5). CONCLUSIONS: These findings indicate that filovirus outbreaks may go undetected in Uganda and people involved in artisan gold mining are more likely to be exposed to infection with either Marburg virus or ebolaviruses, likely due to increased risk of exposure to bats. This calls for active surveillance in known high-risk areas for early detection and response to prevent filovirus epidemics.


Assuntos
Surtos de Doenças , Ebolavirus/imunologia , Doença pelo Vírus Ebola/diagnóstico , Doença pelo Vírus Ebola/epidemiologia , Doença do Vírus de Marburg/diagnóstico , Doença do Vírus de Marburg/epidemiologia , Marburgvirus/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Quirópteros/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Doença pelo Vírus Ebola/sangue , Humanos , Masculino , Doença do Vírus de Marburg/sangue , Pessoa de Meia-Idade , Mineradores , Estudos Retrospectivos , Estudos Soroepidemiológicos , Uganda/epidemiologia , Adulto Jovem
8.
Trends Biotechnol ; 38(9): 943-947, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32600777

RESUMO

Vaccine solutions rarely reach the public until after an outbreak abates; an Ebola vaccine was approved 5 years after peak outbreak and SARS, MERS, and Zika vaccines are still in clinical development. Despite massive leaps forward in rapid science, other regulatory bottlenecks are hamstringing the global effort for pandemic vaccines.


Assuntos
Infecções por Coronavirus/prevenção & controle , Aprovação de Drogas/organização & administração , Doença pelo Vírus Ebola/prevenção & controle , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/biossíntese , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Vacinas contra Ebola/administração & dosagem , Vacinas contra Ebola/biossíntese , Ebolavirus/efeitos dos fármacos , Ebolavirus/imunologia , Ebolavirus/patogenicidade , Europa (Continente)/epidemiologia , Saúde Global/tendências , Regulamentação Governamental , Doença pelo Vírus Ebola/epidemiologia , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/virologia , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/biossíntese , Influenza Humana/epidemiologia , Influenza Humana/imunologia , Influenza Humana/virologia , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Vírus da SARS/efeitos dos fármacos , Vírus da SARS/imunologia , Vírus da SARS/patogenicidade , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Síndrome Respiratória Aguda Grave/virologia , Estados Unidos/epidemiologia , Vacinas Virais/administração & dosagem , Zika virus/efeitos dos fármacos , Zika virus/imunologia , Zika virus/patogenicidade , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/prevenção & controle , Infecção por Zika virus/virologia
9.
Nat Commun ; 11(1): 3730, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32709840

RESUMO

Long-term follow up studies from Ebola virus disease (EVD) survivors (EBOV_S) are lacking. Here, we evaluate immune and gene expression profiles in 35 Guinean EBOV_S from the last West African outbreak, a median of 23 months (IQR [18-25]) after discharge from treatment center. Compared with healthy donors, EBOV_S exhibit increases of blood markers of inflammation, intestinal tissue damage, T cell and B cell activation and a depletion of circulating dendritic cells. All survivors have EBOV-specific IgG antibodies and robust and polyfunctional EBOV-specific memory T-cell responses. Deep sequencing of the genes expressed in blood reveals an enrichment in 'inflammation' and 'antiviral' pathways. Integrated analyses identify specific immune markers associated with the persistence of clinical symptoms. This study identifies a set of biological and genetic markers that could be used to define a signature of "chronic Ebola virus disease (CEVD)".


Assuntos
Ebolavirus/imunologia , Doença pelo Vírus Ebola/complicações , Doença pelo Vírus Ebola/imunologia , Doenças do Sistema Imunitário/complicações , Doenças do Sistema Imunitário/imunologia , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antivirais/farmacologia , Linfócitos B/imunologia , Citocinas/sangue , Ebolavirus/efeitos dos fármacos , Ebolavirus/genética , Feminino , Marcadores Genéticos , Doença pelo Vírus Ebola/tratamento farmacológico , Doença pelo Vírus Ebola/virologia , Humanos , Doenças do Sistema Imunitário/genética , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Inflamação/genética , Ativação Linfocitária , Masculino , Sobreviventes , Linfócitos T/imunologia , Transcriptoma , Adulto Jovem
10.
J Cell Mol Med ; 24(12): 6988-6999, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32374474

RESUMO

Outbreaks of infections with viruses like Sars-CoV-2, Ebola virus and Zika virus lead to major global health and economic problems because of limited treatment options. Therefore, new antiviral drug candidates are urgently needed. The promising new antiviral drug candidate silvestrol effectively inhibited replication of Corona-, Ebola-, Zika-, Picorna-, Hepatis E and Chikungunya viruses. Besides a direct impact on pathogens, modulation of the host immune system provides an additional facet to antiviral drug development because suitable immune modulation can boost innate defence mechanisms against the pathogens. In the present study, silvestrol down-regulated several pro- and anti-inflammatory cytokines (IL-6, IL-8, IL-10, CCL2, CCL18) and increased TNF-α during differentiation and activation of M1-macrophages, suggesting that the effects of silvestrol might cancel each other out. However, silvestrol amplified the anti-inflammatory potential of M2-macrophages by increasing expression of anti-inflammatory surface markers CD206, TREM2 and reducing release of pro-inflammatory IL-8 and CCL2. The differentiation of dendritic cells in the presence of silvestrol is characterized by down-regulation of several surface markers and cytokines indicating that differentiation is impaired by silvestrol. In conclusion, silvestrol influences the inflammatory status of immune cells depending on the cell type and activation status.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Citocinas/genética , Células Dendríticas/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Macrófagos/efeitos dos fármacos , Triterpenos/farmacologia , Betacoronavirus/crescimento & desenvolvimento , Betacoronavirus/imunologia , Diferenciação Celular/efeitos dos fármacos , Vírus Chikungunya/efeitos dos fármacos , Vírus Chikungunya/crescimento & desenvolvimento , Vírus Chikungunya/imunologia , Citocinas/classificação , Citocinas/imunologia , Células Dendríticas/imunologia , Células Dendríticas/virologia , Ebolavirus/efeitos dos fármacos , Ebolavirus/crescimento & desenvolvimento , Ebolavirus/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Vírus da Hepatite E/efeitos dos fármacos , Vírus da Hepatite E/crescimento & desenvolvimento , Vírus da Hepatite E/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/virologia , Especificidade de Órgãos , Picornaviridae/efeitos dos fármacos , Picornaviridae/crescimento & desenvolvimento , Picornaviridae/imunologia , Cultura Primária de Células , Transdução de Sinais , Zika virus/efeitos dos fármacos , Zika virus/crescimento & desenvolvimento , Zika virus/imunologia
11.
Rev Med Suisse ; 16(690): 739-743, 2020 Apr 15.
Artigo em Francês | MEDLINE | ID: mdl-32301308

RESUMO

The Ebola virus disease outbreak raging in the North-Kivu and Ituri provinces of Democratic Republic of the Congo already accounts for more than 3400 cases, from which 2200 died. Major progress have been achieved since the 2014-2016 West Africa outbreak. A vaccine is now approved by the European Medicine Agency and has been administered to more than 250 000 volunteers in the field. New specific antiviral treatments are now available. Ebola virus disease shifted from a deadly disease to a preventable, curable one. However, the long-lasting conflict and repeated attacks of civilians and health workers hampers the control of the outbreak.


Assuntos
Antivirais/provisão & distribução , Surtos de Doenças/estatística & dados numéricos , Vacinas contra Ebola/provisão & distribução , Doença pelo Vírus Ebola/tratamento farmacológico , Doença pelo Vírus Ebola/epidemiologia , África Ocidental/epidemiologia , Antivirais/uso terapêutico , República Democrática do Congo/epidemiologia , Vacinas contra Ebola/administração & dosagem , Ebolavirus/efeitos dos fármacos , Ebolavirus/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos
12.
Transfusion ; 60(5): 1024-1031, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32129478

RESUMO

BACKGROUND: In 2014, passive immunization by transfusion of Ebola convalescent plasma (ECP) was considered for treating patients with acute Ebola virus disease (EVD). Early Ebola virus (EBOV) seroconversion confers a survival advantage in natural infection, hence transfusion of ECP plasma with high levels of neutralizing EBOV antibodies is a potential passive immune therapy. Techniques to reduce the risk of other transfusion-transmitted infections (TTIs) are warranted as recent ECP survivors are ineligible as routine blood donors. As part of an ongoing clinical trial to evaluate the safety and effectiveness of ECP, the impact of amotosalen/UVA pathogen reduction technology (PRT) on EBOV antibody characteristics was examined. STUDY DESIGN AND METHODS: Serum and plasma samples were collected from EVD-recovered subjects at multiple timepoints and evaluated by ELISA for antibodies to recombinant EBOV glycoprotein (GP) and irradiated whole EBOV antigen, as well as for EBOV microneutralization, classic plaque reduction neutralization test (PRNT) and EBOV pseudovirion neutralization assay (PsVNA) activity. RESULTS: Six subjects donated 40 individual ECP units. Substantial antibody titers and neutralizing activity results were demonstrated but were generally lower for the ACD plasma samples compared to the serum samples. Anti-EBOV titers by all assays remained essentially unchanged after PRT. CONCLUSION: Treatment of ECP with PRT to reduce the risk of TTI did not significantly reduce EBOV IgG antibody titers or neutralizing activity. Although ECP was used in the treatment of repatriated patients, no PRT units from this study were transfused to EVD patients. This inventory of PRT-treated ECP is currently available for future clinical evaluation.


Assuntos
Anticorpos Neutralizantes/análise , Doadores de Sangue , Ebolavirus/imunologia , Doença pelo Vírus Ebola/sangue , Imunidade Ativa , Plasma/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Anticorpos Antivirais/uso terapêutico , Chlorocebus aethiops , Convalescença , Ficusina/farmacologia , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Imunidade Ativa/fisiologia , Imunização Passiva/métodos , Testes de Neutralização , Plasma/efeitos dos fármacos , Soroconversão/fisiologia , Estados Unidos , Células Vero , Carga Viral/efeitos dos fármacos , Carga Viral/imunologia
13.
J Virol ; 94(11)2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32213610

RESUMO

Ebola virus (EBOV) continues to pose a significant threat to human health, as evidenced by the 2013-2016 epidemic in West Africa and the ongoing outbreak in the Democratic Republic of the Congo. EBOV causes hemorrhagic fever, organ damage, and shock culminating in death, with case fatality rates as high as 90%. This high lethality combined with the paucity of licensed medical countermeasures makes EBOV a critical human pathogen. Although EBOV infection results in significant damage to the liver and the adrenal glands, little is known about the molecular signatures of injury in these organs. Moreover, while changes in peripheral blood cells are becoming increasingly understood, the host responses within organs and lymphoid tissues remain poorly characterized. To address this knowledge gap, we tracked longitudinal transcriptional changes in tissues collected from EBOV-Makona-infected cynomolgus macaques. Following infection, both liver and adrenal glands exhibited significant and early downregulation of genes involved in metabolism, coagulation, hormone synthesis, and angiogenesis; upregulated genes were associated with inflammation. Analysis of lymphoid tissues showed early upregulation of genes that play a role in innate immunity and inflammation and downregulation of genes associated with cell cycle and adaptive immunity. Moreover, transient activation of innate immune responses and downregulation of humoral immune responses in lymphoid tissues were confirmed with flow cytometry. Together, these data suggest that the liver, adrenal gland, and lymphatic organs are important sites of EBOV infection and that dysregulating the function of these vital organs contributes to the development of Ebola virus disease.IMPORTANCE Ebola virus (EBOV) remains a high-priority pathogen since it continues to cause outbreaks with high case fatality rates. Although it is well established that EBOV results in severe organ damage, our understanding of tissue injury in the liver, adrenal glands, and lymphoid tissues remains limited. We begin to address this knowledge gap by conducting longitudinal gene expression studies in these tissues, which were collected from EBOV-infected cynomolgus macaques. We report robust and early gene expression changes within these tissues, indicating they are primary sites of EBOV infection. Furthermore, genes involved in metabolism, coagulation, and adaptive immunity were downregulated, while inflammation-related genes were upregulated. These results indicate significant tissue damage consistent with the development of hemorrhagic fever and lymphopenia. Our study provides novel insight into EBOV-host interactions and elucidates how host responses within the liver, adrenal glands, and lymphoid tissues contribute to EBOV pathogenesis.


Assuntos
Glândulas Suprarrenais , Ebolavirus , Regulação Viral da Expressão Gênica/imunologia , Doença pelo Vírus Ebola , Fígado , Tecido Linfoide , Doenças dos Macacos , Transcrição Genética/imunologia , Glândulas Suprarrenais/imunologia , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/patologia , Glândulas Suprarrenais/virologia , Animais , Ebolavirus/imunologia , Ebolavirus/metabolismo , Feminino , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/metabolismo , Doença pelo Vírus Ebola/patologia , Doença pelo Vírus Ebola/veterinária , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Tecido Linfoide/imunologia , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Tecido Linfoide/virologia , Macaca fascicularis , Masculino , Doenças dos Macacos/imunologia , Doenças dos Macacos/metabolismo , Doenças dos Macacos/patologia , Doenças dos Macacos/virologia
15.
Immunity ; 52(2): 217-219, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32075725

RESUMO

Antibodies are key components to prevent and treat Ebola virus disease (EVD). In this issue of Immunity, Gilchuk et al. decipher the underlying mechanism of two antibodies that cooperatively target Ebolaviruses. The study provides insight into an antibody combination that potentiates antiviral activity and is able to prevent EVD in nonhuman primates.


Assuntos
Ebolavirus/imunologia , Doença pelo Vírus Ebola , Animais , Anticorpos Monoclonais , Anticorpos Neutralizantes , Anticorpos Antivirais
16.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32075939

RESUMO

The 2013-2016 Ebola outbreak in West Africa led to accelerated efforts to develop vaccines against these highly virulent viruses. A live, recombinant vesicular stomatitis virus-based vaccine has been deployed in outbreak settings and appears highly effective. Vaccines based on replication-deficient adenovirus vectors either alone or in combination with a multivalent modified vaccinia Ankara (MVA) Ebola vaccine also appear promising and are progressing in clinical evaluation. However, the ability of current live vector-based approaches to protect against multiple pathogenic species of Ebola is not yet established, and eliciting durable responses may require additional booster vaccinations. Here, we report the development of a bivalent, spherical Ebola virus-like particle (VLP) vaccine that incorporates glycoproteins (GPs) from Zaire Ebola virus (EBOV) and Sudan Ebola virus (SUDV) and is designed to extend the breadth of immunity beyond EBOV. Immunization of rabbits with bivalent Ebola VLPs produced antibodies that neutralized all four pathogenic species of Ebola viruses and elicited antibody-dependent cell-mediated cytotoxicity (ADCC) responses against EBOV and SUDV. Vaccination of rhesus macaques with bivalent VLPs generated strong humoral immune responses, including high titers of binding, as well as neutralizing antibodies and ADCC responses. VLP vaccination led to a significant increase in the frequency of Ebola GP-specific CD4 and CD8 T cell responses. These results demonstrate that a novel bivalent Ebola VLP vaccine elicits strong humoral and cellular immune responses against pathogenic Ebola viruses and support further evaluation of this approach as a potential addition to Ebola vaccine development efforts.IMPORTANCE Ebola outbreaks result in significant morbidity and mortality in affected countries. Although several leading candidate Ebola vaccines have been developed and advanced in clinical testing, additional vaccine candidates may be needed to provide protection against different Ebola species and to extend the durability of protection. A novel approach demonstrated here is to express two genetically diverse glycoproteins on a spherical core, generating a vaccine that can broaden immune responses against known pathogenic Ebola viruses. This approach provides a new method to broaden and potentially extend protective immune responses against Ebola viruses.


Assuntos
Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , África Ocidental , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Feminino , Glicoproteínas/imunologia , Imunização , Macaca mulatta , Masculino , Vacinação , Vacinas Atenuadas , Vacinas de Partículas Semelhantes a Vírus/imunologia , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia
17.
J Virol ; 94(8)2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32051271

RESUMO

Given that the Ebola virus (EBOV) infects a wide array of organs and cells yet displays a relative lack of neurotropism, we asked whether a chimeric vesicular stomatitis virus (VSV) expressing the EBOV glycoprotein (GP) might selectively target brain tumors. The mucin-like domain (MLD) of the EBOV GP may enhance virus immune system evasion. Here, we compared chimeric VSVs in which EBOV GP replaces the VSV glycoprotein, thereby reducing the neurotoxicity associated with wild-type VSV. A chimeric VSV expressing the full-length EBOV GP (VSV-EBOV) containing the MLD was substantially more effective and safer than a parallel construct with an EBOV GP lacking the MLD (VSV-EBOVΔMLD). One-step growth, reverse transcription-quantitative PCR, and Western blotting assessments showed that VSV-EBOVΔMLD produced substantially more progeny faster than VSV-EBOV. Using immunodeficient SCID mice, we focused on targeting human brain tumors with these VSV-EBOVs. Similar to the findings of our previous study in which we used an attenuated VSV-EBOV with no MLD that expressed green fluorescent protein (GFP) (VSV-EBOVΔMLD-GFP), VSV-EBOVΔMLD without GFP targeted glioma but yielded only a modest extension of survival. In contrast, VSV-EBOV containing the MLD showed substantially better targeting and elimination of brain tumors after intravenous delivery and increased the survival of brain tumor-bearing mice. Despite the apparent destruction of most tumor cells by VSV-EBOVΔMLD, the virus remained active within the SCID mouse brain and showed widespread infection of normal brain cells. In contrast, VSV-EBOV eliminated the tumors and showed relatively little infection of normal brain cells. Parallel experiments with direct intracranial virus infection generated similar results. Neither VSV-EBOV nor VSV-EBOVΔMLD showed substantive infection of the brains of normal immunocompetent mice.IMPORTANCE The Ebola virus glycoprotein contains a mucin-like domain which may play a role in immune evasion. Chimeric vesicular stomatitis viruses with the EBOV glycoprotein substituted for the VSV glycoprotein show greater safety and efficacy in targeting brain tumors in immunodeficient mice when the MLD was expressed within the EBOV glycoprotein than when EBOV lacked the mucin-like domain.


Assuntos
Neoplasias Encefálicas/metabolismo , Ebolavirus/imunologia , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/virologia , Mucinas/imunologia , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ebolavirus/genética , Glioblastoma/virologia , Glioma/patologia , Glioma/virologia , Proteínas de Fluorescência Verde , Xenoenxertos , Humanos , Camundongos , Camundongos SCID , Mucinas/genética , Vírus da Estomatite Vesicular Indiana/imunologia
18.
Cell Host Microbe ; 27(2): 163-165, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32053784

RESUMO

Ebolavirus disease is a global threat. In this issue, Khurana et al. reveal the antibody response against all ebolavirus proteins by analyzing longitudinal antibody repertoires of an Ebola survivor from disease onset. Antibodies against VP40 and GP are found to predominate and two protective antigenic sites in GP identified.


Assuntos
Ebolavirus/imunologia , Doença pelo Vírus Ebola , Anticorpos Antivirais , Humanos , Proteoma , Sobreviventes
19.
Cell Host Microbe ; 27(2): 262-276.e4, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32053790

RESUMO

Evolution of antibody repertoire against the Ebola virus (EBOV) proteome was characterized in an acutely infected patient receiving supportive care alone to elucidate virus-host interactions over time. Differential kinetics are observed for IgM-IgG-IgA epitope diversity, antibody binding, and affinity maturation to EBOV proteins. During acute illness, antibodies predominate to VP40 and glycoprotein (GP). At day 13 of clinical illness, a marked increase in antibody titers to most EBOV proteins and affinity maturation to GP is associated with rapid decline in viral replication and illness severity. At one year, despite undetectable virus, a diverse IgM repertoire against VP40 and GP epitopes is observed suggesting occult viral persistence. Rabbit immunization experiments identify key immunodominant sites of GP, while challenge studies in mice found these epitopes induce EBOV-neutralizing antibodies and protect against lethal EBOV challenge. This study reveals markers of viral persistence and provides promising approaches for development and evaluation of vaccines and therapeutics.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Animais , Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Epitopos/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/terapia , Humanos , Imunoglobulina A/isolamento & purificação , Imunoglobulina G/isolamento & purificação , Imunoglobulina M/isolamento & purificação , Camundongos , Proteoma/imunologia , Coelhos , Sobreviventes , Proteínas do Envelope Viral/imunologia , Proteínas da Matriz Viral/imunologia , Proteínas Virais/imunologia , Vacinas Virais
20.
Immunity ; 52(2): 388-403.e12, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32023489

RESUMO

Structural principles underlying the composition of protective antiviral monoclonal antibody (mAb) cocktails are poorly defined. Here, we exploited antibody cooperativity to develop a therapeutic mAb cocktail against Ebola virus. We systematically analyzed the antibody repertoire in human survivors and identified a pair of potently neutralizing mAbs that cooperatively bound to the ebolavirus glycoprotein (GP). High-resolution structures revealed that in a two-antibody cocktail, molecular mimicry was a major feature of mAb-GP interactions. Broadly neutralizing mAb rEBOV-520 targeted a conserved epitope on the GP base region. mAb rEBOV-548 bound to a glycan cap epitope, possessed neutralizing and Fc-mediated effector function activities, and potentiated neutralization by rEBOV-520. Remodeling of the glycan cap structures by the cocktail enabled enhanced GP binding and virus neutralization. The cocktail demonstrated resistance to virus escape and protected non-human primates (NHPs) against Ebola virus disease. These data illuminate structural principles of antibody cooperativity with implications for development of antiviral immunotherapeutics.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Ebolavirus/imunologia , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Linhagem Celular , Modelos Animais de Doenças , Quimioterapia Combinada , Epitopos , Feminino , Glicoproteínas/química , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Macaca mulatta , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mimetismo Molecular , Conformação Proteica
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