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1.
Front Immunol ; 12: 635701, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34489923

RESUMO

Serological testing is a powerful tool in epidemiological studies for understanding viral circulation and assessing the effectiveness of virus control measures, as is the case of SARS-CoV-2, the pathogenic agent of COVID-19. Immunoassays can quantitatively reveal the concentration of antiviral antibodies. The assessment of antiviral antibody titers may provide information on virus exposure, and changes in IgG levels are also indicative of a reduction in viral circulation. In this work, we describe a serological study for the evaluation of antiviral IgG and IgM antibodies and their correlation with antiviral activity. The serological assay for IgG detection used two SARS-CoV-2 proteins as antigens, the nucleocapsid N protein and the 3CL protease. Cross-reactivity tests in animals have shown high selectivity for detection of antiviral antibodies, using both the N and 3CL antigens. Using samples of human serum from individuals previously diagnosed by PCR for COVID-19, we observed high sensitivity of the ELISA assay. Serological results with human samples also suggest that the combination of higher titers of antiviral IgG antibodies to different antigen targets may be associated with greater neutralization activity, which can be enhanced in the presence of antiviral IgM antibodies.


Assuntos
Anticorpos Antivirais/imunologia , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/prevenção & controle , Vigilância Imunológica , SARS-CoV-2/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , COVID-19/epidemiologia , COVID-19/imunologia , Teste Sorológico para COVID-19/normas , Reações Cruzadas , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Camundongos , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade , Zika virus/imunologia
2.
Cell Host Microbe ; 29(9): 1333-1335, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34499857

RESUMO

SARS-CoV-2 has mutually illuminated our collective knowledge and knowledge gaps, particularly in antiviral defense and therapeutic strategies. A recent study in Science (Poirier et al., 2021) uncovers an ancient antiviral mechanism that mammals utilize to suppress viruses, including SARS-CoV-2 and Zika virus, that could have broad implications for therapeutic strategies.


Assuntos
Proteínas Argonauta/metabolismo , COVID-19/prevenção & controle , Interferons/imunologia , Interferência de RNA/fisiologia , Ribonuclease III/metabolismo , Infecção por Zika virus/prevenção & controle , Animais , Linhagem Celular , Células HEK293 , Humanos , RNA Interferente Pequeno/genética , RNA Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Replicação Viral , Zika virus/genética , Zika virus/imunologia
3.
N Engl J Med ; 385(12): e35, 2021 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-34525286

RESUMO

BACKGROUND: Although Zika virus (ZIKV) infection is typically self-limiting, other associated complications such as congenital birth defects and the Guillain-Barré syndrome are well described. There are no approved vaccines against ZIKV infection. METHODS: In this phase 1, open-label clinical trial, we evaluated the safety and immunogenicity of a synthetic, consensus DNA vaccine (GLS-5700) encoding the ZIKV premembrane and envelope proteins in two groups of 20 participants each. The participants received either 1 mg or 2 mg of vaccine intradermally, with each injection followed by electroporation (the use of a pulsed electric field to introduce the DNA sequence into cells) at baseline, 4 weeks, and 12 weeks. RESULTS: The median age of the participants was 38 years, and 60% were women; 78% were White and 22% Black; in addition, 30% were Hispanic. At the interim analysis at 14 weeks (i.e., after the third dose of vaccine), no serious adverse events were reported. Local reactions at the vaccination site (e.g., injection-site pain, redness, swelling, and itching) occurred in approximately 50% of the participants. After the third dose of vaccine, binding antibodies (as measured on enzyme-linked immunosorbent assay) were detected in all the participants, with geometric mean titers of 1642 and 2871 in recipients of 1 mg and 2 mg of vaccine, respectively. Neutralizing antibodies developed in 62% of the samples on Vero-cell assay. On neuronal-cell assay, there was 90% inhibition of ZIKV infection in 70% of the serum samples and 50% inhibition in 95% of the samples. The intraperitoneal injection of postvaccination serum protected 103 of 112 IFNAR knockout mice (bred with deletion of genes encoding interferon-α and interferon-ß receptors) (92%) that were challenged with a lethal dose of ZIKV-PR209 strain; none of the mice receiving baseline serum survived the challenge. Survival was independent of the neutralization titer. CONCLUSIONS: In this phase 1, open-label clinical trial, a DNA vaccine elicited anti-ZIKV immune responses. Further studies are needed to better evaluate the safety and efficacy of the vaccine. (Funded by GeneOne Life Science and others; ZIKA-001 ClinicalTrials.gov number, NCT02809443.).


Assuntos
Anticorpos Neutralizantes/sangue , Imunogenicidade da Vacina , Vacinas de DNA , Vacinas Virais/imunologia , Infecção por Zika virus/prevenção & controle , Zika virus/imunologia , Adulto , Animais , Anticorpos Antivirais/sangue , Feminino , Humanos , Injeções Intradérmicas/efeitos adversos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Linfócitos T/fisiologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/efeitos adversos , Vacinas de DNA/imunologia , Infecção por Zika virus/imunologia
4.
Viruses ; 13(7)2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34372551

RESUMO

BACKGROUND: In 2015-2016, a large Zika virus (ZIKV) outbreak occurred in the Americas. Although the exact ZIKV antibody kinetics after infection are unknown, recent evidence indicates the rapid waning of ZIKV antibodies in humans. Therefore, we aimed to determine the levels of ZIKV antibodies more than three years after a ZIKV infection. METHODS: We performed ZIKV virus neutralization tests (VNT) and a commercial ZIKV non-structural protein 1 (NS1) IgG ELISA in a cohort of 49 participants from Suriname who had a polymerase-chain-reaction-confirmed ZIKV infection more than three years ago. Furthermore, we determined the presence of antibodies against multiple dengue virus (DENV) antigens. RESULTS: The ZIKV seroprevalence in this cohort, assessed with ZIKV VNT and ZIKV NS1 IgG ELISA, was 59.2% and 63.3%, respectively. There was, however, no correlation between these two tests. Furthermore, we did not find evidence of a potential negative influence of DENV immunity on ZIKV antibody titers. CONCLUSIONS: ZIKV seroprevalence, assessed with two commonly used serological tests, was lower than expected in this cohort of participants who had a confirmed previous ZIKV infection. This can have implications for future ZIKV seroprevalence studies and possibly for the duration of immunological protection after a ZIKV infection.


Assuntos
Anticorpos Neutralizantes/análise , Infecção por Zika virus/imunologia , Zika virus/imunologia , Adulto , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , Estudos de Coortes , Reações Cruzadas/imunologia , Dengue/virologia , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , Testes de Neutralização/métodos , Estudos Soroepidemiológicos , Testes Sorológicos/métodos , Suriname , Zika virus/patogenicidade , Infecção por Zika virus/metabolismo , Infecção por Zika virus/virologia
5.
J Gen Virol ; 102(8)2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34410903

RESUMO

An infectious agent's pathogenic and transmission potential is heavily influenced by early events during the asymptomatic or subclinical phase of disease. During this phase, the presence of infectious agent may be relatively low. An important example of this is Zika virus (ZIKV), which can cross the placenta and infect the foetus, even in mothers with subclinical infections. These subclinical infections represent roughly 80 % of all human infections. Initial ZIKV pathogenesis studies were performed in type I interferon receptor (IFNAR) knockout mice. Blunting the interferon response resulted in robust infectivity, and increased the utility of mice to model ZIKV infections. However, due to the removal of the interferon response, the use of these models impedes full characterization of immune responses to ZIKV-related pathologies. Moreover, IFNAR-deficient models represent severe disease whereas less is known regarding subclinical infections. Investigation of the anti-viral immune response elicited at the maternal-foetal interface is critical to fully understand mechanisms involved in foetal infection, foetal development, and disease processes recognized to occur during subclinical maternal infections. Thus, immunocompetent experimental models that recapitulate natural infections are needed. We have established subclinical intravaginal ZIKV infections in mice and guinea pigs. We found that these infections resulted in: the presence of both ZIKV RNA transcripts and infectious virus in maternal and placental tissues, establishment of foetal infections and ZIKV-mediated CXCL10 expression. These models will aid in discerning the mechanisms of subclinical ZIKV mother-to-offspring transmission, and by extension can be used to investigate other maternal infections that impact foetal development.


Assuntos
Feto , Placenta , Complicações Infecciosas na Gravidez , Infecção por Zika virus/virologia , Zika virus , Animais , Chlorocebus aethiops , Feminino , Feto/imunologia , Feto/virologia , Cobaias , Humanos , Transmissão Vertical de Doenças Infecciosas , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Placenta/imunologia , Placenta/virologia , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/virologia , Células Vero , Zika virus/imunologia , Zika virus/patogenicidade
6.
Nat Commun ; 12(1): 4051, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193875

RESUMO

Zika virus (ZIKV) has emerged as an important global health threat, with the recently acquired capacity to cause severe neurological symptoms and to persist within host tissues. We previously demonstrated that an early Asian lineage ZIKV isolate induces a highly activated CD8 T cell response specific for an immunodominant epitope in the ZIKV envelope protein in wild-type mice. Here we show that a contemporary ZIKV isolate from the Brazilian outbreak severely limits CD8 T cell immunity in mice and blocks generation of the immunodominant CD8 T cell response. This is associated with a more sustained infection that is cleared between 7- and 14-days post-infection. Mechanistically, we demonstrate that infection with the Brazilian ZIKV isolate reduces the cross-presentation capacity of dendritic cells and fails to fully activate the immunoproteasome. Thus, our study provides an isolate-specific mechanism of host immune evasion by one Brazilian ZIKV isolate, which differs from the early Asian lineage isolate and provides potential insight into viral persistence associated with recent ZIKV outbreaks.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epitopos Imunodominantes/imunologia , Proteínas do Envelope Viral/imunologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Animais , Apresentação do Antígeno , Brasil , Células Cultivadas , Chlorocebus aethiops , Modelos Animais de Doenças , Evasão da Resposta Imune , Camundongos , Camundongos Endogâmicos C57BL , Zika virus/isolamento & purificação , Zika virus/patogenicidade , Infecção por Zika virus/patologia , Infecção por Zika virus/virologia
7.
Science ; 373(6551): 231-236, 2021 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244417

RESUMO

In mammals, early resistance to viruses relies on interferons, which protect differentiated cells but not stem cells from viral replication. Many other organisms rely instead on RNA interference (RNAi) mediated by a specialized Dicer protein that cleaves viral double-stranded RNA. Whether RNAi also contributes to mammalian antiviral immunity remains controversial. We identified an isoform of Dicer, named antiviral Dicer (aviD), that protects tissue stem cells from RNA viruses-including Zika virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-by dicing viral double-stranded RNA to orchestrate antiviral RNAi. Our work sheds light on the molecular regulation of antiviral RNAi in mammalian innate immunity, in which different cell-intrinsic antiviral pathways can be tailored to the differentiation status of cells.


Assuntos
RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Interferência de RNA , Vírus de RNA/fisiologia , RNA Viral/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo , Células-Tronco/enzimologia , Células-Tronco/virologia , Processamento Alternativo , Animais , Encéfalo/enzimologia , Encéfalo/virologia , Linhagem Celular , RNA Helicases DEAD-box/química , Humanos , Imunidade Inata , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Camundongos , Organoides/enzimologia , Organoides/virologia , Infecções por Vírus de RNA/enzimologia , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/virologia , Vírus de RNA/genética , Vírus de RNA/imunologia , RNA de Cadeia Dupla/metabolismo , RNA Interferente Pequeno/metabolismo , Ribonuclease III/química , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Replicação Viral , Zika virus/genética , Zika virus/imunologia , Zika virus/fisiologia , Infecção por Zika virus/enzimologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia
8.
Nat Immunol ; 22(8): 958-968, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34267374

RESUMO

Antibody-dependent enhancement (ADE) is an important safety concern for vaccine development against dengue virus (DENV) and its antigenically related Zika virus (ZIKV) because vaccine may prime deleterious antibodies to enhance natural infections. Cross-reactive antibodies targeting the conserved fusion loop epitope (FLE) are known as the main sources of ADE. We design ZIKV immunogens engineered to change the FLE conformation but preserve neutralizing epitopes. Single vaccination conferred sterilizing immunity against ZIKV without ADE of DENV-serotype 1-4 infections and abrogated maternal-neonatal transmission in mice. Unlike the wild-type-based vaccine inducing predominately cross-reactive ADE-prone antibodies, B cell profiling revealed that the engineered vaccines switched immunodominance to dispersed patterns without DENV enhancement. The crystal structure of the engineered immunogen showed the dimeric conformation of the envelope protein with FLE disruption. We provide vaccine candidates that will prevent both ZIKV infection and infection-/vaccination-induced DENV ADE.


Assuntos
Anticorpos Facilitadores/imunologia , Antígenos Virais/imunologia , Reações Cruzadas/imunologia , Vacinas contra Dengue/imunologia , Dengue/prevenção & controle , Zika virus/imunologia , Aedes , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Chlorocebus aethiops , Cricetinae , Vírus da Dengue/imunologia , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptor de Interferon alfa e beta/genética , Vacinação , Células Vero , Infecção por Zika virus/imunologia , Infecção por Zika virus/prevenção & controle
9.
J Virol ; 95(19): e0061921, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34232731

RESUMO

Although transmission of Zika virus (ZIKV) in the Americas has greatly declined since late 2017, recent reports of reduced risks of symptomatic Zika by prior dengue virus (DENV) infection and increased risks of severe dengue disease by previous ZIKV or DENV infection underscore a critical need for serological tests that can discriminate past ZIKV, DENV, and/or other flavivirus infections and improve our understanding of the immune interactions between these viruses and vaccine strategy in endemic regions. As serological tests for ZIKV primarily focus on envelope (E) and nonstructural protein 1 (NS1), antibodies to other ZIKV proteins have not been explored. Here, we employed Western blot analysis using antigens of 6 flaviviruses from 3 serocomplexes to investigate antibody responses following reverse transcription-PCR (RT-PCR)-confirmed ZIKV infection. Panels of 20 primary ZIKV and 20 ZIKV with previous DENV infection recognized E proteins of all 6 flaviviruses and the NS1 protein of ZIKV with some cross-reactivity to DENV. While the primary ZIKV panel recognized only the premembrane (prM) protein of ZIKV, the ZIKV with previous DENV panel recognized both ZIKV and DENV prM proteins. Analysis of antibody responses following 42 DENV and 18 West Nile virus infections revealed similar patterns of recognition by anti-E and anti-NS1 antibodies, whereas both panels recognized the prM protein of the homologous serocomplex but not others. The specificity was further supported by analysis of sequential samples. Together, these findings suggest that anti-prM antibody is a flavivirus serocomplex-specific marker and can be used to delineate current and past flavivirus infections in endemic areas. IMPORTANCE Despite a decline in Zika virus (ZIKV) transmission since late 2017, questions regarding its surveillance, potential reemergence, and interactions with other flaviviruses in regions where it is endemic remain unanswered. Recent studies have reported reduced risks of symptomatic Zika by prior dengue virus (DENV) infection and increased risks of severe dengue disease by previous ZIKV or DENV infection, highlighting a need for better serological tests to discriminate past ZIKV, DENV, and/or other flavivirus infections and improved understanding of the immune interactions and vaccine strategy for these viruses. As most serological tests for ZIKV focused on envelope and nonstructural protein 1, antibodies to other ZIKV proteins, including potentially specific antibodies, remain understudied. We employed Western blot analysis using antigens of 6 flaviviruses to study antibody responses following well-documented ZIKV, DENV, and West Nile virus infections and identified anti-premembrane antibody as a flavivirus serocomplex-specific marker to delineate current and past flavivirus infections in areas where flaviviruses are endemic.


Assuntos
Anticorpos Antivirais/sangue , Dengue/imunologia , Proteínas do Envelope Viral/imunologia , Febre do Nilo Ocidental/imunologia , Infecção por Zika virus/imunologia , Anticorpos Antivirais/imunologia , Western Blotting , Reações Cruzadas , Dengue/diagnóstico , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Sensibilidade e Especificidade , Proteínas não Estruturais Virais/imunologia , Febre do Nilo Ocidental/diagnóstico , Vírus do Nilo Ocidental/imunologia , Zika virus/imunologia , Infecção por Zika virus/diagnóstico
10.
BMC Infect Dis ; 21(1): 704, 2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34303348

RESUMO

BACKGROUND: The co-circulation of types of arbovirus in areas where they are endemic increased the risk of outbreaks and limited the diagnostic methods available. Here, we analyze the epidemiological profile of DENV, CHIKV and ZIKV at the serological and molecular level in patients with suspected infection with these arboviruses in the city of Juazeiro do Norte, Ceará, Brazil. METHODS: In 2016, the Central Public Health Laboratory (LACEN) of Juazeiro do Norte received 182 plasma samples from patients who visited health facilities with symptoms compatible with arbovirus infection. The LACEN performed serological tests for detection of IgM/IgG to DENV and CHIKV. They then sent these samples to the Retrovirology Laboratory of the Federal University of São Paulo and Faculty of Medical of the ABC where molecular analyses to confirm the infection by DENV, ZIKV and CHIKV were performed. The prevalence of IgM/IgG antibodies and of infections confirmed by RT-qPCR were presented with 95% confidence interval. RESULTS: In serologic analysis, 125 samples were positive for antibodies against CHIKV and all were positive for antibodies against DENV. A higher prevalence of IgG against CHIKV (63.20% with 95% CI: 45.76-70.56) than against DENV (95.05% with 95% CI: 78.09-98.12) was observed. When the samples were submitted to analysis by RT-qPCR, we observed the following prevalence: mono-infection by ZIKV of 19.23% (95% CI: 14.29-34.82) patients, mono-infection by CHIKV of 3.84% (95% CI: 2.01-5.44) and co-infection with ZIKV and CHIKV of 1.09% (95% CI: 0.89-4.56). CONCLUSION: The serologic and molecular tests performed in this study were effective in analyzing the epidemiological profile of DENV, CHIKV and ZIKV in patients with suspected infection by these arboviruses in the city of Juazeiro do Norte, Ceará/Brazil.


Assuntos
Anticorpos Antivirais/sangue , Febre de Chikungunya/epidemiologia , Vírus Chikungunya/imunologia , Vírus da Dengue/imunologia , Dengue/epidemiologia , Infecção por Zika virus/epidemiologia , Zika virus/imunologia , Adulto , Brasil/epidemiologia , Febre de Chikungunya/terapia , Cidades/epidemiologia , Estudos Transversais , Dengue/terapia , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Reação em Cadeia da Polimerase em Tempo Real , Medição de Risco , Testes Sorológicos , Infecção por Zika virus/terapia
11.
J Virol ; 95(16): e0222020, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34076485

RESUMO

Following the Zika virus (ZIKV) outbreak in the Americas, ZIKV was causally associated with microcephaly and a range of neurological and developmental symptoms, termed congenital Zika syndrome (CZS). The viruses responsible for this outbreak belonged to the Asian lineage of ZIKV. However, in vitro and in vivo studies assessing the pathogenesis of African-lineage ZIKV demonstrated that African-lineage isolates often replicated to high titers and caused more-severe pathology than Asian-lineage isolates. To date, the pathogenesis of African-lineage ZIKV in a translational model, particularly during pregnancy, has not been rigorously characterized. Here, we infected four pregnant rhesus macaques with a low-passage-number strain of African-lineage ZIKV and compared its pathogenesis to those for a cohort of four pregnant rhesus macaques infected with an Asian-lineage isolate and a cohort of mock-inoculated controls. The viral replication kinetics for the two experimental groups were not significantly different, and both groups developed robust neutralizing antibody titers above levels considered to be protective. There was no evidence of significant fetal head growth restriction or gross fetal harm at delivery (1 to 1.5 weeks prior to full term) in either group. However, a significantly higher burden of ZIKV viral RNA (vRNA) was found in the maternal-fetal interface tissues of the macaques exposed to an African-lineage isolate. Our findings suggest that ZIKV of any genetic lineage poses a threat to pregnant individuals and their infants. IMPORTANCE ZIKV was first identified in 1947 in Africa, but most of our knowledge of ZIKV is based on studies of the distinct Asian genetic lineage, which caused the outbreak in the Americas in 2015 to 2016. In its most recent update, the WHO stated that improved understanding of African-lineage ZIKV pathogenesis during pregnancy must be a priority. The recent detection of African-lineage isolates in Brazil underscores the need to understand the impact of these viruses. Here, we provide the first comprehensive assessment of African-lineage ZIKV infection during pregnancy in a translational nonhuman primate model. We show that African-lineage isolates replicate with kinetics similar to those of Asian-lineage isolates and can infect the placenta. However, there was no evidence of more-severe outcomes with African-lineage isolates. Our results highlight both the threat that African-lineage ZIKV poses to pregnant individuals and their infants and the need for epidemiological and translational in vivo studies with African-lineage ZIKV.


Assuntos
Placenta/virologia , Complicações Infecciosas na Gravidez/virologia , Replicação Viral , Infecção por Zika virus/virologia , Zika virus/fisiologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Modelos Animais de Doenças , Feminino , Desenvolvimento Fetal , Cinética , Macaca mulatta , Placenta/patologia , Gravidez , Zika virus/classificação , Zika virus/imunologia
12.
J Virol ; 95(16): e0057321, 2021 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-34076486

RESUMO

The 2015/2016 Zika virus epidemic in South and Central America left the scientific community urgently trying to understand the factors that contribute to Zika virus pathogenesis. Because multiple other flaviviruses are endemic in areas where Zika virus emerged, it is hypothesized that a key to understanding Zika virus disease severity is to study Zika virus infection in the context of prior flavivirus exposure. Human and animal studies have highlighted the idea that having been previously exposed to a different flavivirus may modulate the immune response to Zika virus. However, it is still unclear how prior flavivirus exposure impacts Zika viral burden and disease. In this murine study, we longitudinally examine multiple factors involved in Zika disease, linking viral burden with increased neurological disease severity, weight loss, and inflammation. We show that prior heterologous flavivirus exposure with dengue virus type 2 or 3 or the vaccine strain of yellow fever provides protection from mortality in a lethal Zika virus challenge. However, reduction in viral burden and Zika disease varies depending on the infecting primary flavivirus; with primary Zika virus infection being most protective from Zika virus challenge, followed by dengue virus 2, with yellow fever and dengue virus 3 protecting against mortality but showing more severe disease. This study demonstrates the variation in protective effects of prior flavivirus exposure on Zika virus pathogenesis and identifies distinct relationships between primary flavivirus infection and the potential for Zika virus disease. IMPORTANCE The emergence and reemergence of various vector-borne diseases in recent years highlights the need to understand the mechanisms of protection for each pathogen. In this study, we investigated the impact of prior exposure to Zika virus, dengue virus serotypes 2 or 3, or the vaccine strain of yellow fever on pathogenesis and disease outcomes in a mouse model of Zika virus infection. We found that prior exposure to a heterologous flavivirus was protective from mortality, and to varying degrees, prior flavivirus exposure was protective against neurological disease, weight loss, and severe viral burden during a lethal Zika challenge. Using a longitudinal and cross-sectional study design, we were able to link multiple disease parameters, including viral burden, with neurological disease severity, weight loss, and inflammatory response in the context of flavivirus infection. This study demonstrates a measurable but varied impact of prior flavivirus exposure in modulating flavivirus pathophysiology. Given the cyclic nature of most flavivirus outbreaks, this work will contribute to the forecasting of disease severity for future outbreaks.


Assuntos
Flavivirus/imunologia , Imunidade Heteróloga , Infecção por Zika virus/imunologia , Zika virus/imunologia , Animais , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/virologia , Proteção Cruzada , Citocinas/metabolismo , Vírus da Dengue/imunologia , Modelos Animais de Doenças , Progressão da Doença , Inflamação , Camundongos , Carga Viral , Viremia/imunologia , Vírus da Febre Amarela/imunologia , Zika virus/patogenicidade , Infecção por Zika virus/mortalidade , Infecção por Zika virus/patologia , Infecção por Zika virus/virologia
13.
PLoS Negl Trop Dis ; 15(6): e0009484, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34086672

RESUMO

The global spread of Zika virus (ZIKV), which caused a pandemic associated with Congenital Zika Syndrome and neuropathology in newborns and adults, prompted the pursuit of a safe and effective vaccine. Here, three kinds of recombinant rabies virus (RABV) encoding the prM-E protein of ZIKV were constructed: ZI-D (prM-E), ZI-E (transmembrane domain (TM) of prM-E replaced with RABV G) and ZI-F (signal peptide and TM domain of prM-E replaced with the region of RABV G). When the TM of prM-E was replaced with the region of RABV G (termed ZI-E), it promoted ZIKV E protein localization on the cell membrane and assembly on recombinant viruses. In addition, the change in the signal peptide with RABV G (termed ZI-F) was not conducive to foreign protein expression. The immunogenicity of recombinant viruses mixed with a complex adjuvant of ISA 201 VG and poly(I:C) was tested in BALB/c mice. After immunization with ZI-E, the anti-ZIKV IgG antibody lasted for at least 10 weeks. The titers of neutralizing antibodies (NAbs) against ZIKV and RABV at week 6 were all greater than the protective titers. Moreover, ZI-E stimulated the proliferation of splenic lymphocytes and promoted the secretion of cytokines. It also promoted the production of central memory T cells (TCMs) among CD4+/CD8+ T cells and stimulated B cell activation and maturation. These results indicate that ZI-E could induce ZIKV-specific humoral and cellular immune responses, which have the potential to be developed into a promising vaccine for protection against both ZIKV and RABV infections.


Assuntos
Vírus da Raiva/genética , Raiva/prevenção & controle , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Infecção por Zika virus/prevenção & controle , Zika virus/imunologia , Animais , Anticorpos Antivirais/imunologia , Feminino , Humanos , Imunidade Celular , Camundongos , Camundongos Endogâmicos BALB C , Raiva/imunologia , Raiva/virologia , Vírus da Raiva/imunologia , Linfócitos T/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética , Zika virus/genética , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia
14.
Anal Bioanal Chem ; 413(19): 4873-4885, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34152457

RESUMO

The incidence of infection by the dengue virus (DENV) has grown dramatically, reaching 128 countries in tropical and subtropical regions worldwide, with a pattern of hyper-endemicity. DENV is a mosquito-borne disease having four serotypes, one or two circulating in epidemic outbreaks. The diagnosis of DENV is challenging mainly due to the circulation of new viruses with remarkable similarities, such as Zika (ZIKV) that may cause fetal microcephaly. DENV affects 390 million people per year, but these numbers may be higher due to the underreported and misclassified cases. Recently, the NS1 nonstructural protein has been described in serum and urine of DENV and ZIKV patients, suggesting its use as a biomarker for screening since a negative NS1 sample confirms the absence of these infections. Herein, a label-free immunosensor comprising an assembled nanostructured thin film of carbon nanotube-ethylenediamine is described. The advantage of in situ electrosynthesis of polymer film is to allow major control of thickness and conductivity, in addition to designing the reactive groups for functionalization. A quartz crystal microbalance system was used to estimate the thickness of the polymeric film obtained. The anti-NS1 monoclonal antibodies were immobilized to carbon nanotubes by covalent linkage, permitting a high stability during measurements. Analytical responses to NS1 were obtained by differential pulse voltammetry (DPV), showing a linear range from 20 to 800 ng mL-1 and reproducibility of 3.0%, with a limit of detection (LOD) of 6.8 ng mL- 1. This immunosensor was capable of detecting ZIKV and DENV NS1 in spiked urine and real serum in a clinical range.Graphical abstract.


Assuntos
Dengue/diagnóstico , Proteínas não Estruturais Virais/sangue , Proteínas não Estruturais Virais/urina , Infecção por Zika virus/diagnóstico , Anticorpos Imobilizados , Anticorpos Antivirais , Dengue/sangue , Dengue/urina , Técnicas Eletroquímicas , Glicoproteínas/sangue , Glicoproteínas/urina , Humanos , Imunoensaio , Membranas Artificiais , Nanoestruturas , Sensibilidade e Especificidade , Testes Sorológicos , Zika virus/imunologia , Infecção por Zika virus/sangue , Infecção por Zika virus/urina
15.
PLoS One ; 16(6): e0252198, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34077451

RESUMO

Once an obscure pathogen, Zika virus (ZIKV) has emerged as a significant global public health concern. Several studies have linked ZIKV infection in pregnant women with the development of microcephaly and other neurological abnormalities, emphasizing the need for a safe and effective vaccine to combat the spread of this disease. Preclinical studies and vaccine development efforts have largely focused on the role of humoral immunity in disease protection. Consequently, relatively little is known in regard to cellular immunity against ZIKV, although an effective vaccine will likely need to engage both the humoral and cellular arms of the immune system. To that end, we utilized two-dimensional liquid chromatography coupled with tandem mass spectrometry to identify 90 ZIKV peptides that were naturally processed and presented on HLA class I and II molecules (HLA-A*02:01/HLA-DRB1*04:01) of an immortalized B cell line infected with ZIKV (strain PRVABC59). Sequence identity clustering was used to filter the number of candidate peptides prior to evaluating memory T cell recall responses in ZIKV convalescent subjects. Peptides that individually elicited broad (4 of 7 subjects) and narrow (1 of 7 subjects) T cell responses were further analyzed using a suite of predictive algorithms and in silico modeling to evaluate HLA binding and peptide structural properties. A subset of nine broadly reactive peptides was predicted to provide robust global population coverage (97.47% class I; 70.74% class II) and to possess stable structural properties amenable for vaccine formulation, highlighting the potential clinical benefit for including ZIKV T cell epitopes in experimental vaccine formulations.


Assuntos
COVID-19/terapia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Adulto , Linfócitos B/imunologia , COVID-19/imunologia , Linhagem Celular , Epitopos de Linfócito T/imunologia , Feminino , Humanos , Imunidade Celular , Imunidade Humoral , Imunização Passiva/métodos , Memória Imunológica , Masculino , Espectrometria de Massas/métodos , Peptídeos/imunologia , Linfócitos T/imunologia , Zika virus/metabolismo , Zika virus/patogenicidade , Infecção por Zika virus/metabolismo , Infecção por Zika virus/virologia
16.
Biosensors (Basel) ; 11(5)2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-34065688

RESUMO

Zika virus (ZIKV) is a mosquito-borne infection, predominant in tropical and subtropical regions causing international concern due to the ZIKV disease having been associated with congenital disabilities, especially microcephaly and other congenital abnormalities in the fetus and newborns. Development of strategies that minimize the devastating impact by monitoring and preventing ZIKV transmission through sexual intercourse, especially in pregnant women, since no vaccine is yet available for the prevention or treatment, is critically important. ZIKV infection is generally asymptomatic and cross-reactivity with dengue virus (DENV) is a global concern. An innovative screen-printed electrode (SPE) was developed for amperometric detection of the non-structural protein (NS2B) of ZIKV by exploring the intrinsic redox catalytic activity of Prussian blue (PB), incorporated into a carbon nanotube-polypyrrole composite. Thus, this immunosensor has the advantage of electrochemical detection without adding any redox-probe solution (probe-less detection), allowing a point-of-care diagnosis. It was responsive to serum samples of only ZIKV positive patients and non-responsive to negative ZIKV patients, even if the sample was DENV positive, indicating a possible differential diagnosis between them by NS2B. All samples used here were confirmed by CDC protocols, and immunosensor responses were also checked in the supernatant of C6/36 and in Vero cell cultures infected with ZIKV.


Assuntos
Técnicas Biossensoriais , Imunoensaio , Zika virus/isolamento & purificação , Ferrocianetos , Humanos , Nanotubos de Carbono , Polímeros , Pirróis , Zika virus/imunologia , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/virologia
18.
Nat Commun ; 12(1): 2619, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976183

RESUMO

After the Zika virus (ZIKV) epidemic in the Americas in 2016, both Zika and dengue incidence declined to record lows in many countries in 2017-2018, but in 2019 dengue resurged in Brazil, causing ~2.1 million cases. In this study we use epidemiological, climatological and genomic data to investigate dengue dynamics in recent years in Brazil. First, we estimate dengue virus force of infection (FOI) and model mosquito-borne transmission suitability since the early 2000s. Our estimates reveal that DENV transmission was low in 2017-2018, despite conditions being suitable for viral spread. Our study also shows a marked decline in dengue susceptibility between 2002 and 2019, which could explain the synchronous decline of dengue in the country, partially as a result of protective immunity from prior ZIKV and/or DENV infections. Furthermore, we performed phylogeographic analyses using 69 newly sequenced genomes of dengue virus serotype 1 and 2 from Brazil, and found that the outbreaks in 2018-2019 were caused by local DENV lineages that persisted for 5-10 years, circulating cryptically before and after the Zika epidemic. We hypothesize that DENV lineages may circulate at low transmission levels for many years, until local conditions are suitable for higher transmission, when they cause major outbreaks.


Assuntos
Vírus da Dengue/imunologia , Dengue/epidemiologia , Suscetibilidade a Doenças/imunologia , Epidemias/estatística & dados numéricos , Infecção por Zika virus/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , Brasil/epidemiologia , Criança , Pré-Escolar , Dengue/imunologia , Dengue/transmissão , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Epidemias/prevenção & controle , Monitoramento Epidemiológico , Feminino , Genoma Viral/genética , Humanos , Imunidade Heteróloga , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Mosquitos Vetores/virologia , Filogeografia , Sorotipagem , Adulto Jovem , Zika virus/imunologia , Infecção por Zika virus/epidemiologia
19.
Lancet Infect Dis ; 21(9): 1282-1292, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34019802

RESUMO

BACKGROUND: Zika virus, a flavivirus transmitted by Aedes aegypti and Aedes albopictus mosquitoes, is associated with cases of congenital malformations and neurological complications. Absence of specific treatment makes a prophylactic Zika virus vaccine an unmet medical need. We assessed safety and immunogenicity of three doses of a purified, inactivated, Zika virus vaccine candidate in healthy flavivirus-naive and flavivirus-primed adults. METHODS: This two-part, multicentre, observer-blind, randomised, placebo-controlled, phase 1 trial was done at seven medical clinics in the USA and two in Puerto Rico. Eligible participants were healthy adults aged 18-49 years. Participants were randomly assigned (1:1:1:1), using a sponsor-supplied randomisation scheme, to four groups to receive two intramuscular injections, 28 days apart, of saline placebo or TAK-426 containing 2 µg, 5 µg, or 10 µg antigen. Participants, investigators, and vaccine administrating personnel were masked to group assignment. Part 1 of the study assessed flavivirus-naive participants and part 2 assessed flavivirus-primed participants. The primary outcomes were safety, tolerability, and immunogenicity based on solicited local reactions and solicited systemic adverse events in the 7 days after each dose; unsolicited adverse events and serious adverse events in the 28 days after each dose; and geometric mean titres (GMTs) of neutralising anti-Zika virus antibodies at 28 days after the second dose. Safety assessments were done in all participants who received at least one dose of vaccine. Immunogenicity assessments were in the per-protocol set, comprising all participants who received at least one dose of vaccine and provided valid serology results at baseline and at least one post-vaccination timepoint, with no major protocol violations. The trial is ongoing and is registered at ClinicalTrials.gov (NCT03343626). FINDINGS: Between Nov 13, 2017, and Oct 24, 2018, 894 volunteers were screened and 271 enrolled (125 flavivirus-naive and 146 flavivirus-primed participants). All TAK-426 doses were well tolerated with no deaths, no vaccine-related serious adverse events, and similar rates of mainly mild to moderate adverse events. TAK-426 elicited dose-dependent increases in antibody GMTs in both flavivirus-naive and flavivirus-primed participants. 28 days after dose 2, plaque-reduction neutralisation test GMTs in flavivirus-naive participants were 1130 (95% CI 749-1703) in the 2 µg TAK-426 group, 1992 (1401-2833) in the 5 µg TAK-426 group, and 3690 (2677-5086) in the 10 µg TAK-426 group. In pairwise comparisons, responses after two vaccinations in the 10 µg group were significantly greater than in the 2 µg group (GMT ratio 3·27 [95% CI 1·98-5·39], p<0·0001) and the 5 µg group (GMT ratio 1·85 [1·15-2·98], p=0·012). INTERPRETATION: TAK-426 was well tolerated, with an acceptable safety profile, and was immunogenic in both flavivirus-naive and flavivirus-primed adults. Based on the safety and immunogenicity profiles of all TAK-426 doses assessed, the 10 µg TAK-426 dose was selected for further clinical development. FUNDING: Takeda Vaccines and the US Biomedical Advanced Research and Development Authority. TRANSLATION: For the Spanish translation of the abstract see Supplementary Materials section.


Assuntos
Imunogenicidade da Vacina , Vacinas de Produtos Inativados/imunologia , Infecção por Zika virus/prevenção & controle , Zika virus/imunologia , Adolescente , Adulto , Anticorpos Antivirais/sangue , Formação de Anticorpos , Bases de Dados Factuais , Método Duplo-Cego , Feminino , Humanos , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Vacinação , Adulto Jovem
20.
Immunology ; 164(2): 386-397, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34056709

RESUMO

There is growing interest in understanding antibody (Ab) function beyond neutralization. The non-structural protein 1 (NS1) of Zika virus (ZIKV) is an attractive candidate for an effective vaccine as Abs against NS1, unlike the envelope or premembrane, do not carry the risk of mediating antibody-dependent enhancement. Our aim was to evaluate whether ZIKV NS1 Abs elicited following natural infection in humans can mediate antibody-dependent cellular cytotoxicity (ADCC). We evaluated the isotype specificity of ZIKV-specific Abs in immune sera and supernatants from stimulated immune PBMC and found that Abs against ZIKV NS1 and virus-like particles were predominantly of the IgG1 isotype. Using a recently developed FluoroSpot assay, we found robust frequencies of NS1-specific Ab-secreting cells in PBMC of individuals who were naturally infected with ZIKV. We developed assays to measure both natural killer cell activation by flow cytometry and target cell lysis of ZIKV NS1-expressing cells using an image cytometry assay in the presence of ZIKV NS1 Abs. Our data indicate efficient opsonization of ZIKV NS1-expressing CEM-NKR cell lines using ZIKV-immune but not ZIKV-naïve sera, a prerequisite of ADCC. Furthermore, sera from immune donors were able to induce both NK cell degranulation and lysis of ZIKV NS1 CEM-NKR cells in vitro. Our data suggest that ADCC is a possible mechanism for ZIKV NS1 Abs to eliminate virally infected target cells.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Proteínas não Estruturais Virais/imunologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Células Cultivadas , Reações Cruzadas/imunologia , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Vacinas Virais/imunologia , Infecção por Zika virus/virologia
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