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2.
Mem Inst Oswaldo Cruz ; 115: e200287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533869

RESUMO

BACKGROUND: The heat-labile nature of Dengue virus (DENV) in serum samples must be considered when applying routine diagnostic tests to avoid issues that could impact the accuracy of test results with direct implications for case management and disease reporting. OBJECTIVES: To check if pre-analytical variables, such as storage time and temperature, have an impact on the accuracy of the main routine diagnostic tests for dengue. METHODS: Virus isolation, reverse transcription real-time polymerase chain reaction (RT-PCR) and NS1 enzyme-linked immunosorbent assay (ELISA) were evaluated using 84 samples submitted to different pre-analytical conditions. FINDINGS: Sensitivity and negative predictive value were directly affected by sample storage conditions. RT-PCR and virus isolation showed greater dependence on well-conserved samples for an accurate diagnosis. Interestingly, even storage at -30ºC for a relatively short time (15 days) was not adequate for accurate results using virus isolation and RT-PCR tests. On the other hand, NS1 ELISA showed no significant reduction in positivity for aliquots tested under the same conditions as in the previous tests. MAIN CONCLUSIONS: Our results support the stability of the NS1 marker in ELISA diagnosis and indicate that the accuracy of routine tests such as virus isolation and RT-PCR is significantly affected by inadequate transport and storage conditions of serum samples.


Assuntos
Antígenos Virais/sangue , Vírus da Dengue/isolamento & purificação , Dengue/diagnóstico , Ensaio de Imunoadsorção Enzimática/métodos , Testes Imunológicos/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Proteínas não Estruturais Virais/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Dengue/sangue , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Humanos , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Proteínas não Estruturais Virais/genética
3.
ACS Sens ; 6(3): 593-612, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33544999

RESUMO

COVID-19, caused by the SARS-CoV-2 virus, has developed into a global health crisis, causing over 2 million deaths and changing people's daily life the world over. Current main-stream diagnostic methods in the laboratory include nucleic acid PCR tests and direct viral antigen tests for detecting active infections, and indirect human antibody tests specific to SARS-CoV-2 to detect prior exposure. In this Perspective, we briefly describe the PCR and antigen tests and then focus mainly on existing antibody tests and their limitations including inaccuracies and possible causes of unreliability. False negatives in antibody immunoassays can arise from assay formats, selection of viral antigens and antibody types, diagnostic testing windows, individual variance, and fluctuation in antibody levels. Reasons for false positives in antibody immunoassays mainly involve antibody cross-reactivity from other viruses, as well as autoimmune disease. The spectrum bias has an effect on both the false negatives and false positives. For assay developers, not only improvement of assay formats but also selection of viral antigens and isotopes of human antibodies need to be carefully considered to improve sensitivity and specificity. For clinicians, the factors influencing the accuracy of assays must be kept in mind to test patients using currently imperfect but available tests with smart tactics and realistic interpretation of the test results.


Assuntos
Anticorpos Antivirais/sangue , /imunologia , Antígenos Virais/sangue , /imunologia , Reações Falso-Negativas , Reações Falso-Positivas , Humanos , Imunoensaio
4.
J Clin Invest ; 131(6)2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497356

RESUMO

Multisystem inflammatory syndrome associated with the SARS-CoV-2 pandemic has recently been described in children (MIS-C), partially overlapping with Kawasaki disease (KD). We hypothesized that (a) MIS-C and prepandemic KD cytokine profiles may be unique and justify the clinical differences observed, and (b) SARS-CoV-2-specific immune complexes (ICs) may explain the immunopathology of MIS-C. Seventy-four children were included: 14 with MIS-C, 9 patients positive for SARS-CoV-2 by PCR without MIS-C (COVID), 14 with prepandemic KD, and 37 healthy controls (HCs). Thirty-four circulating cytokines were quantified in pretreatment serum or plasma samples and the presence of circulating SARS-CoV-2 ICs was evaluated in MIS-C patients. Compared with HCs, the MIS-C and KD groups showed most cytokines to be significantly elevated, with IFN-γ-induced response markers (including IFN-γ, IL-18, and IP-10) and inflammatory monocyte activation markers (including MCP-1, IL-1α, and IL-1RA) being the main triggers of inflammation. In linear discriminant analysis, MIS-C and KD profiles overlapped; however, a subgroup of MIS-C patients (MIS-Cplus) differentiated from the remaining MIS-C patients in IFN-γ, IL-18, GM-CSF, RANTES, IP-10, IL-1α, and SDF-1 and incipient signs of macrophage activation syndrome. Circulating SARS-CoV-2 ICs were not detected in MIS-C patients. Our findings suggest a major role for IFN-γ in the pathogenesis of MIS-C, which may be relevant for therapeutic management.


Assuntos
/etiologia , Citocinas/sangue , Síndrome de Linfonodos Mucocutâneos/etiologia , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Adolescente , Anticorpos Antivirais/sangue , Complexo Antígeno-Anticorpo/sangue , Antígenos Virais/sangue , /virologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Lactente , Interferon gama/sangue , Masculino , Modelos Imunológicos , Síndrome de Linfonodos Mucocutâneos/imunologia , Pandemias , /imunologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Síndrome de Resposta Inflamatória Sistêmica/virologia
5.
Viruses ; 13(2)2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33494175

RESUMO

Zika virus (ZIKV) RNA has been found to remain in human semen for up to one year after infection, but the presence of Flavivirus antigens in the different compartments of semen has been largely unexplored. Following the introduction of ZIKV in Nicaragua (2016), a prospective study of patients with clinical symptoms consistent with ZIKV was conducted in León to investigate virus shedding in different fluids. ZIKV infection was confirmed in 16 male subjects (≥18 years of age) by RT-qPCR in either blood, saliva or urine. Of these, three provided semen samples at 7, 14, 21, 28, 60 and 180 days postsymptom onset (DPSO) for Flavivirus antigens and RNA studies. These cases were compared with 19 asymptomatic controls. Flavivirus antigens were examined by immunofluorescence (IF) using the 4G2 Mabs, and confocal microscopy was used to explore fluorescence patterns. The three (100%) symptomatic subjects and 3 (16%) of the 19 asymptomatic subjects had Flavivirus antigens and viral RNA in the spermatozoa fraction. The percentage of IF Flavivirus-positive spermatozoa cells ranged from 1.9% to 25% in specimens from symptomatic subjects, as compared with 0.8% to 3.8% in specimens from asymptomatic controls. A marked IF-pattern in the cytoplasmic droplets and tail of the spermatozoa was observed. The sperm concentrations (45 × 106/mL vs. 63.5 × 106/mL, p = 0.041) and the total motility percentage (54% vs. 75%, p = 0.009) were significantly lower in specimens from ZIKV-positive than in those of ZIKV-negative. In conclusion, this study demonstrated the presence of Flavivirus antigens and RNA within a time frame of 28 DPSO in sperm cells of symptomatic and asymptomatic subjects during the ZIKV epidemic. These findings have implications for public health, in terms of nonarthropod-born, silent transmission facilitated by sperm cells and potential transmission from asymptomatic males to pregnant women, with consequences to the fetus.


Assuntos
Antígenos Virais/análise , Flavivirus/isolamento & purificação , RNA Viral/análise , Espermatozoides/virologia , Infecção por Zika virus/virologia , Zika virus/isolamento & purificação , Adulto , Antígenos Virais/sangue , Antígenos Virais/urina , Flavivirus/genética , Imunofluorescência , Humanos , Masculino , RNA Viral/sangue , RNA Viral/urina , Reação em Cadeia da Polimerase em Tempo Real , Saliva/virologia , Sêmen/virologia , Espermatozoides/química , Eliminação de Partículas Virais , Adulto Jovem , Zika virus/genética
6.
JCI Insight ; 6(4)2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33497357

RESUMO

Four endemic human coronaviruses (HCoVs) are commonly associated with acute respiratory infection in humans. B cell responses to these "common cold" viruses remain incompletely understood. Here we report a comprehensive analysis of CoV-specific antibody repertoires in 231 children and 1168 adults using phage immunoprecipitation sequencing. Seroprevalence of antibodies against endemic HCoVs ranged between approximately 4% and 27% depending on the species and cohort. We identified at least 136 novel linear B cell epitopes. Antibody repertoires against endemic HCoVs were qualitatively different between children and adults in that anti-HCoV IgG specificities more frequently found among children targeted functionally important and structurally conserved regions of the spike, nucleocapsid, and matrix proteins. Moreover, antibody specificities targeting the highly conserved fusion peptide region and S2' cleavage site of the spike protein were broadly cross-reactive with peptides of epidemic human and nonhuman coronaviruses. In contrast, an acidic tandem repeat in the N-terminal region of the Nsp3 subdomain of the HCoV-HKU1 polyprotein was the predominant target of antibody responses in adult donors. Our findings shed light on the dominant species-specific and pan-CoV target sites of human antibody responses to coronavirus infection, thereby providing important insights for the development of prophylactic or therapeutic monoclonal antibodies and vaccine design.


Assuntos
Anticorpos Antivirais/isolamento & purificação , Resfriado Comum/virologia , Infecções por Coronavirus/imunologia , Coronavirus/imunologia , Doenças Endêmicas , Adulto , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Especificidade de Anticorpos , Antígenos Virais/sangue , Antígenos Virais/imunologia , Criança , Pré-Escolar , Resfriado Comum/sangue , Resfriado Comum/epidemiologia , Resfriado Comum/imunologia , Coronavirus/isolamento & purificação , Infecções por Coronavirus/sangue , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Reações Cruzadas , Epitopos de Linfócito B/sangue , Epitopos de Linfócito B/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Domínios Proteicos/imunologia , Estudos Retrospectivos , Estudos Soroepidemiológicos , Proteínas Virais/imunologia
8.
Nat Commun ; 12(1): 6, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397903

RESUMO

The current practice for diagnosis of COVID-19, based on SARS-CoV-2 PCR testing of pharyngeal or respiratory specimens in a symptomatic patient at high epidemiologic risk, likely underestimates the true prevalence of infection. Serologic methods can more accurately estimate the disease burden by detecting infections missed by the limited testing performed to date. Here, we describe the validation of a coronavirus antigen microarray containing immunologically significant antigens from SARS-CoV-2, in addition to SARS-CoV, MERS-CoV, common human coronavirus strains, and other common respiratory viruses. A comparison of antibody profiles detected on the array from control sera collected prior to the SARS-CoV-2 pandemic versus convalescent blood specimens from virologically confirmed COVID-19 cases demonstrates near complete discrimination of these two groups, with improved performance from use of antigen combinations that include both spike protein and nucleoprotein. This array can be used as a diagnostic tool, as an epidemiologic tool to more accurately estimate the disease burden of COVID-19, and as a research tool to correlate antibody responses with clinical outcomes.


Assuntos
Anticorpos Antivirais/sangue , Antígenos Virais/sangue , /imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , /diagnóstico , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Análise em Microsséries/métodos , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Testes de Neutralização , Vírus da SARS/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
9.
Med Microbiol Immunol ; 210(1): 65-72, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33452927

RESUMO

Successful containment strategies for the SARS-CoV-2 pandemic will depend on reliable diagnostic assays. Point-of-care antigen tests (POCT) may provide an alternative to time-consuming PCR tests to rapidly screen for acute infections on site. Here, we evaluated two SARS-CoV-2 antigen tests: the STANDARD™ F COVID-19 Ag FIA (FIA) and the SARS-CoV-2 Rapid Antigen Test (RAT). For diagnostic assessment, we used a large set of PCR-positive and PCR-negative respiratory swabs from asymptomatic and symptomatic patients and health care workers in the setting of two University Hospitals in Munich, Germany, i.e. emergency rooms, patient care units or employee test centers. For FIA, overall clinical sensitivity and specificity were 45.4% (n = 381) and 97.8% (n = 360), respectively, and for RAT, 50.3% (n = 445) and 97.7% (n = 386), respectively. For primary diagnosis of asymptomatic and symptomatic individuals, diagnostic sensitivities were 60.9% (FIA) (n = 189) and 64.5% (RAT) (n = 256). This questions these tests' utility for the reliable detection of acute SARS-CoV-2-infected individuals, in particular in high-risk settings. We support the proposal that convincing high-quality outcome data on the impact of false-negative and false-positive antigen test results need to be obtained in a POCT setting. Moreover, the efficacy of alternative testing strategies to complement PCR assays must be evaluated by independent laboratories, prior to widespread implementation in national and international test strategies.


Assuntos
/métodos , /imunologia , Adulto , Antígenos Virais/sangue , Criança , Pré-Escolar , Reações Falso-Negativas , Reações Falso-Positivas , Alemanha , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , /isolamento & purificação , Sensibilidade e Especificidade
10.
Bioanalysis ; 13(1): 13-28, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33319585

RESUMO

Aim: Coronavirus disease 2019 antibody testing often relies on venous blood collection, which is labor-intensive, inconvenient and expensive compared with finger-stick capillary dried blood spot (DBS) collection. The purpose of our work was to determine if two commercially available anti-severe acute respiratory syndrome coronavirus 2 enzyme-linked immunosorbent assays for IgG antibodies against spike S1 subunit and nucleocapsid proteins could be validated for use with DBS. Materials & methods: Kit supplied reagents were used to extract DBS, and in-house DBS calibrators were included on every run. Results: Positive/negative concordance between DBS and serum was 100/99.3% for the spike S1 subunit assay and 100/98% for the nucleocapsid assay. Conclusion: Validation of the DBS Coronavirus disease 2019 IgG antibody assays demonstrated that serum and DBS can produce equivalent results with minimal kit modifications.


Assuntos
/normas , Teste em Amostras de Sangue Seco/normas , Ensaio de Imunoadsorção Enzimática/normas , /imunologia , Anticorpos Antivirais/química , Antígenos Virais/sangue , Antígenos Virais/imunologia , /imunologia , /sangue , Feminino , Humanos , Imunoglobulina G/química , Masculino , Pessoa de Meia-Idade , Fosfoproteínas/sangue , Fosfoproteínas/imunologia , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/sangue , Glicoproteína da Espícula de Coronavírus/imunologia
11.
Rev. esp. quimioter ; 33(6): 466-484, dic. 2020. ilus, tab, mapas, graf
Artigo em Espanhol | IBECS | ID: ibc-195995

RESUMO

La alta transmisibilidad del SARS-CoV-2 antes y poco después de la aparición de los síntomas sugiere que sólo diagnosticar y aislar a pacientes sintomáticos puede no ser suficiente para interrumpir la propagación de la infección; por ello son también necesarias medidas de salud pública como el distanciamiento social. Adicionalmente será importante detectar a los nuevos infectados que permanecen asintomáticos, que pueden ascender al 50% o más de los casos. Las técnicas moleculares son el patrón de referencia para el diagnóstico de infección por SARS-CoV-2. Sin embargo, el uso masivo de estas técnicas ha generado algunos problemas. Por un lado, la escasez de los recursos (analizadores, fungibles y reactivos), y por otro el retraso en la notificación de resultados. Estos dos hechos se traducen en un retraso en la aplicación de las medidas de aislamiento entre casos y contactos, lo que favorece la expansión de la infección. Las pruebas de detección de antígenos son también métodos de diagnóstico directo, con la ventaja de obtener el resultado en pocos minutos y en el mismo lugar de atención. Además, la sencillez y el bajo coste de estas pruebas permiten repetirlas en días sucesivos en determinados contextos clínicos. La sensibilidad de las pruebas de antígenos es generalmente menor que la de las que detectan ácidos nucleicos, si bien su especificidad es comparable. Se ha comprobado que las pruebas antigénicas tienen más validez en los días alrededor del inicio de síntomas, cuando la carga viral en nasofaringe es mayor. Disponer de un análisis de detección viral rápido y en tiempo real como la prueba de antígenos se ha demostrado más útil para controlar la expansión de la infección que pruebas más sensibles, pero de mayor coste y tiempo de respuesta, como son las pruebas moleculares. Las principales instituciones sanitarias como la OMS, los CDC y el propio Ministerio de Sanidad del Gobierno de España plantean el uso de las pruebas antigénicas en una amplia variedad de estrategias para responder a la pandemia. El presente documento pretende servir de apoyo a los médicos implicados en la atención de pacientes con sospecha de infección por SC2, en el contexto de una incidencia creciente en España desde septiembre de 2020 que representa ya la segunda onda pandémica de COVID-19


The high transmissibility of SARS-CoV-2 before and shortly after the onset of symptoms suggests that only diagnosing and isolating symptomatic patients may not be sufficient to interrupt the spread of infection; therefore, public health measures such as personal distancing are also necessary. Additionally, it will be important to detect the newly infected individuals who remain asymptomatic, which may account for 50% or more of the cases. Molecular techniques are the "gold standard" for the diagnosis of SARS-CoV-2 infection. However, the massive use of these techniques has generated some problems. On the one hand, the scarcity of resources (analyzers, fungibles and reagents), and on the other the delay in the notification of results. These two facts translate into a lag in the application of isolation measures among cases and contacts, which favors the spread of the infection. Antigen detection tests are also direct diagnostic methods, with the advantage of obtaining the result in a few minutes and at the very "pointof-care". Furthermore, the simplicity and low cost of these tests allow them to be repeated on successive days in certain clinical settings. The sensitivity of antigen tests is generally lower than that of nucleic acid tests, although their specificity is comparable. Antigenic tests have been shown to be more valid in the days around the onset of symptoms, when the viral load in the nasopharynx is higher. Having a rapid and real-time viral detection assay such as the antigen test has been shown to be more useful to control the spread of the infection than more sensitive tests, but with greater cost and response time, such as in case of molecular tests. The main health institutions such as the WHO, the CDC and the Ministry of Health of the Government of Spain propose the use of antigenic tests in a wide variety of strategies to respond to the pandemic. This document aims to support physicians involved in the care of patients with suspected SC2 infection, in the context of a growing incidence in Spain since September 2020, which already represents the second pandemic wave of COVID-19


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pandemias , Doença Aguda , Distribuição por Idade , Busca de Comunicante , Incidência , Nasofaringe/virologia , Sensibilidade e Especificidade
13.
Colomb Med (Cali) ; 51(2): e4272, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33012887

RESUMO

In the past four months SARS-CoV-2 has reached most countries in the world. Public health strategies based on widespread testing and proper isolation of positive cases have shown to be helpful to reduce local transmission of SARS-CoV-2. Confirmatory tests, that identify viral RNA, and screening serological tests that identify viral antigens or host antibodies against viral proteins are part of the tools that nations can use to fight infectious disease epidemics. Understanding how each test works can provide insights about their test characteristics and how they can be used for different clinical and public health goals. Testing is a key strategy to reduce viral transmission, not only for this epidemic, but also for others to come.


Assuntos
Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Antígenos Virais/sangue , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Humanos , América Latina/epidemiologia , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Saúde Pública , RNA Viral/isolamento & purificação
14.
mBio ; 11(5)2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33082264

RESUMO

An accurate diagnostic test for early severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is the key weapon to control the coronavirus disease 2019 (COVID-19) pandemic. We previously reported that the SARS-CoV-2 genome contains a unique orf8 accessory gene absent from other human-pathogenic coronaviruses. Here, we characterized the SARS-CoV-2 orf8 as a novel immunogenic secreted protein and utilized it for the accurate diagnosis of COVID-19. Extracellular orf8 protein was detected in cell culture supernatant and in sera of COVID-19 patients. In addition, orf8 was found highly immunogenic in COVID-19 patients, who showed early seropositivity for anti-orf8 IgM, IgG, and IgA. We hypothesize that orf8 secretion during SARS-CoV-2 infection facilitates early mounting of B cell response. The serological test detecting anti-orf8 IgG antibody can be used for the early and accurate diagnosis of COVID-19.IMPORTANCE Current commercially available serological tests for COVID-19 patients are detecting antibodies against SARS-CoV-2 nucleoprotein and spike glycoprotein. The antinucleoprotein and antispike antibodies can be accurately detected in patients during the mid or late stage of infection, and therefore, these assays have not been widely used for early diagnosis of COVID-19. In this study, we characterized the secretory property of a SARS-CoV-2 orf8 protein and proposed that orf8 secretion during infection facilitates early mounting of the B cell response. We demonstrated the presence of anti-orf8 antibodies in both symptomatic and asymptomatic patients during the early stage of infection, while the anti-N antibody is not detected. Our serological test detecting anti-orf8 antibodies may facilitate the development of early and accurate diagnosis for COVID-19.


Assuntos
Antígenos Virais/imunologia , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Proteínas Virais/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Antígenos Virais/metabolismo , Linhagem Celular , Infecções por Coronavirus/sangue , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/sangue , Pandemias , Pneumonia Viral/sangue , Proteínas Virais/sangue , Proteínas Virais/metabolismo
16.
Biosens Bioelectron ; 169: 112572, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916610

RESUMO

Convalescent serum with a high abundance of neutralization IgG is a promising therapeutic agent for rescuing COVID-19 patients in the critical stage. Knowing the concentration of SARS-CoV-2 S1-specific IgG is crucial in selecting appropriate convalescent serum donors. Here, we present a portable microfluidic ELISA technology for rapid (15 min), quantitative, and sensitive detection of anti-SARS-CoV-2 S1 IgG in human serum with only 8 µL sample volume. We first identified a humanized monoclonal IgG that has a high binding affinity and a relatively high specificity towards SARS-CoV-2 S1 protein, which can subsequently serve as the calibration standard of anti-SARS-CoV-2 S1 IgG in serological analyses. We then measured the abundance of anti-SARS-CoV-2 S1 IgG in 16 convalescent COVID-19 patients. Due to the availability of the calibration standard and the large dynamic range of our assay, we were able to identify "qualified donors" for convalescent serum therapy with only one fixed dilution factor (200 ×). Finally, we demonstrated that our technology can sensitively detect SARS-CoV-2 antigens (S1 and N proteins) with pg/mL level sensitivities in 40 min. Overall, our technology can greatly facilitate rapid, sensitive, and quantitative analysis of COVID-19 related markers for therapeutic, diagnostic, epidemiologic, and prognostic purposes.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Infecções por Coronavirus/virologia , Ensaio de Imunoadsorção Enzimática/instrumentação , Imunoglobulina G/sangue , Técnicas Analíticas Microfluídicas/instrumentação , Pneumonia Viral/virologia , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Antígenos Virais/sangue , Antígenos Virais/imunologia , Técnicas Biossensoriais/economia , Técnicas Biossensoriais/instrumentação , Infecções por Coronavirus/terapia , Ensaio de Imunoadsorção Enzimática/economia , Desenho de Equipamento , Humanos , Imunização Passiva , Imunoglobulina G/imunologia , Limite de Detecção , Medições Luminescentes/economia , Medições Luminescentes/instrumentação , Técnicas Analíticas Microfluídicas/economia , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/terapia , Fatores de Tempo , Adulto Jovem
17.
Emerg Microbes Infect ; 9(1): 1965-1973, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32819220

RESUMO

Serology is a crucial part of the public health response to the ongoing SARS-CoV-2 pandemic. Here, we describe the development, validation and clinical evaluation of a protein micro-array as a quantitative multiplex immunoassay that can identify S and N-directed SARS-CoV-2 IgG antibodies with high specificity and sensitivity and distinguish them from all currently circulating human coronaviruses. The method specificity was 100% for SARS-CoV-2 S1 and 96% for N antigen based on extensive syndromic (n=230 cases) and population panel (n=94) testing that also confirmed the high prevalence of seasonal human coronaviruses. To assess its potential role for both SARS-CoV-2 patient diagnostics and population studies, we evaluated a large heterogeneous COVID-19 cohort (n=330) and found an overall sensitivity of 89% (≥ 21 days post onset symptoms (dps)), ranging from 86% to 96% depending on severity of disease. For a subset of these patients longitudinal samples were provided up to 56 dps. Mild cases showed absent or delayed, and lower SARS-CoV-2 antibody responses. Overall, we present the development and extensive clinical validation of a multiplex coronavirus serological assay for syndromic testing, to answer research questions regarding to antibody responses, to support SARS-CoV-2 diagnostics and to evaluate epidemiological developments efficiently and with high-throughput.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Proteínas do Nucleocapsídeo/sangue , Pneumonia Viral/diagnóstico , Glicoproteína da Espícula de Coronavírus/sangue , Idoso , Antígenos Virais/sangue , Antígenos Virais/imunologia , Betacoronavirus/patogenicidade , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/virologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Testes de Neutralização , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Fosfoproteínas , Pneumonia Viral/imunologia , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Análise Serial de Proteínas , Vírus da SARS/imunologia , Vírus da SARS/patogenicidade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/imunologia
18.
Anticancer Res ; 40(7): 3983-3990, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32620641

RESUMO

BACKGROUND/AIM: Few studies have studied micro hepatic vein invasion in hepatocellular carcinoma (HCC). We explored the correlation between hepatic vein invasion and hepatitis B/C virus infection. PATIENTS AND METHODS: Between April 2000 and February 2018, 869 patients underwent liver resection for HCC at a single center. The patients were divided into two groups: those with micro hepatic vein invasion (VV+) and those without (VV-). The clinical data, overall survival (OS) and correlations with the presence of hepatitis B and C viruses were investigated. RESULTS: There were 817 VV- patients and 43 VV+ patients. OS was 66.2 months for VV- patients and 9.9 months for VV+ patients (p=0.0010). VV+ patients had significantly higher levels of serum HBV DNA (p=0.016). CONCLUSION: HCC patients with micro hepatic vein invasion showed significantly shorter OS. A higher level of HBV DNA appears to be a risk factor for micro hepatic vein invasion.


Assuntos
Carcinoma Hepatocelular/patologia , Veias Hepáticas/patologia , Neoplasias Hepáticas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/sangue , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , DNA Viral/sangue , Feminino , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite B/patologia , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite C/patologia , Hepatite C/virologia , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
19.
Artigo em Inglês | MEDLINE | ID: mdl-32491144

RESUMO

Eleven lactating women were inadvertently vaccinated with 17DD yellow fever vaccine in a small city of Sao Paulo State, Brazil. Their infants were being exclusively breast-fed and the breastfeeding was interrupted for 10 days. Serum and breastmilk were collected from the vaccinated mothers and tested for the presence of genomic RNA of the vaccine strain 8, 10 and 15 days after vaccination. Viral RNA was not detected in any of the serum and human milk samples tested and the infants remained asymptomatic. Our result strengthens the effectineness of stopping breastfeeding for 10 days after the inadvertent yellow fever vaccination of lactating women.


Assuntos
Aleitamento Materno/efeitos adversos , Leite Humano/virologia , Vacina contra Febre Amarela/efeitos adversos , Febre Amarela/prevenção & controle , Vírus da Febre Amarela/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Brasil , Feminino , Humanos , Recém-Nascido , RNA Viral/sangue , Febre Amarela/transmissão , Vacina contra Febre Amarela/administração & dosagem
20.
Am J Med Sci ; 360(4): 402-405, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32591093

RESUMO

Dermatomyositis is an inflammatory disorder involving muscle and skin. Similar to many other autoimmune diseases, environmental factors appear to trigger the onset of disease in some cases. Many drugs have been reported to be associated with dermatomyositis, and rarely infections have been described as potential triggering agents. Here we are describing a case of dermatomyositis that developed after doxycycline and levofloxacin use, who also had recent Epstein-Barr virus infection. Dermatomyositis associated with doxycycline or levofloxacin use has not yet been described in the literature, while reports of dermatomyositis after Epstein-Barr virus infection have been rare and limited to juvenile dermatomyositis or in association with cancer. It is important for clinicians to be aware of this rare association so that the diagnosis and treatment can be exercised promptly.


Assuntos
Antibacterianos/efeitos adversos , Dermatomiosite/induzido quimicamente , Dermatomiosite/virologia , Doxiciclina/efeitos adversos , Infecções por Vírus Epstein-Barr/complicações , Levofloxacino/efeitos adversos , Antígenos Virais/sangue , Proteínas do Capsídeo/sangue , Dermatomiosite/sangue , Dermatomiosite/tratamento farmacológico , Infecções por Vírus Epstein-Barr/sangue , Antígenos Nucleares do Vírus Epstein-Barr/sangue , Humanos , Resultado do Tratamento
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