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1.
PLoS One ; 15(11): e0240006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33180782

RESUMO

Serological surveys have been conducted to establish prevalence for COVID-19 antibodies in various cohorts and communities, reporting a wide range of outcomes. The prevalence of such antibodies among healthcare workers, presumed at higher risk for infection, has been increasingly investigated, more studies are needed to better understand the risks and infection transmission in different healthcare settings. The present study reports on initial sero-surveillance conducted on healthcare workers at a regional hospital system in Orange County, California, during May and June, 2020. Study subjects were recruited from the entire hospital employee workforce and the independent medical staff. Data were collected for job duties and locations, COVID-19 symptoms, a PCR test history, travel record since January 2020, and existence of household contacts with COVID-19. A blood sample was collected from each subject for serum analysis for IgG antibodies to SARS-CoV-2. Of 2,992 tested individuals, a total 2,924 with complete data were included in the analysis. Observed prevalence of 1.06% (31 antibody positive cases), adjusted prevalence of 1.13% for test sensitivity and specificity were identified. Significant group differences between positive vs. negative were observed for age (z = 2.65, p = .008), race (p = .037), presence of fever (p < .001), and loss of smell (p < .001), but not for occupations (p = .710). Possible explanation for this low prevalence includes a relatively low local geographic community prevalence (~4.4%) at the time of testing, the hospital's timely procurement of personal protective equipment, rigorous employee education, patient triage, and treatment protocol development and implementation. In addition, cross-reactive adaptive T cell mediated immunity, as recently described, may possibly play a greater role in healthcare workers than in the general population.


Assuntos
Infecções por Coronavirus/epidemiologia , Pessoal de Saúde/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Adulto , Anticorpos Antivirais/análise , Betacoronavirus , California/epidemiologia , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Prevalência , Sensibilidade e Especificidade
3.
Arch Virol ; 165(12): 2829-2835, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33000310

RESUMO

The swine pathogen porcine circovirus type 2 (PCV2) causes significant economic damage worldwide. The PCV2 capsid (CP) residues 169-STIDYFQPNNKR-180 have been identified as a decoy epitope that diverts the host immune response away from protective epitopes. However, the decoy epitope may include important linear or conformational protective epitopes against PCV2. In this study, we used the baculovirus system to express recombinant complete CP (1-233) and mutant CP (Δ169-180), in which the decoy epitope was deleted, and evaluated the immune response to these in mice. Immunization with mutant CP (Δ169-180) protein, which formed very low level of virus-like particles (VLPs), elicited significantly lower levels of PCV2 CP-specific IgG antibodies and a slightly lower neutralizing activity than immunization with the complete CP (1-233) protein. This finding suggests that the complete CP is important for efficient VLP assembly and induction of PCV2-specific IgG antibodies and neutralizing antibodies in mice. This study may provide useful information for next-generation vaccine design for PCV2 control.


Assuntos
Proteínas do Capsídeo/imunologia , Circovirus/imunologia , Epitopos/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Anticorpos Neutralizantes/análise , Anticorpos Antivirais/análise , Proteínas do Capsídeo/biossíntese , Proteínas do Capsídeo/genética , Circovirus/genética , Epitopos/biossíntese , Epitopos/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Síndrome Definhante Multissistêmico de Suínos Desmamados/imunologia , Síndrome Definhante Multissistêmico de Suínos Desmamados/prevenção & controle , Suínos , Vacinação , Vacinas de Partículas Semelhantes a Vírus/genética
4.
Sci Rep ; 10(1): 16615, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024203

RESUMO

Middle East Respiratory Syndrome coronavirus (MERS-CoV) is a highly virulent pathogen that causes Middle East Respiratory Syndrome (MERS). Anti-MERS-CoV antibodies play an integral role in the prevention and treatment against MERS-CoV infections. Bioactivity is a key quality attribute of therapeutic antibodies, and high accuracy and precision are required. The major methods for evaluating the antiviral effect of antiviral antibodies include neutralization assays using live viruses or pseudoviruses are highly variable. Recent studies have demonstrated that the antibody-dependent cellular cytotoxicity (ADCC) activity of antiviral antibodies is more consistent with the virus clearance effect in vivo than neutralization activity. However, no reports evaluating the ADCC activity of anti-MERS antibodies have been published to date. Here, we describe the development of a robust and reliable cell-based reporter gene assay for the determination of ADCC activity of anti-MERS antibodies using 293T/MERS cells stably expressing the spike protein of MERS-CoV (MERS-S) as target cells and the engineered Jurkat/NFAT-luc/FcγRIIIa stably expressing FcγRIIIA and NFAT reporter gene as effector cells. According to the ICH-Q2 analytical method guidelines, we carefully optimized the experimental conditions and assessed the performance of our assay. In addition, we found that the ADCC activity of afucosylated anti-MERS antibodies is higher than their fucosylated counterparts. The establishment of this ADCC determination system provides a novel method for evaluating the bioactivity of anti-MERS antibodies and improving ADCC activity through modification of N-glycosylation of the Fc segment.


Assuntos
Anticorpos Antivirais/análise , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Infecções por Coronavirus/imunologia , Testes Imunológicos de Citotoxicidade/métodos , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Infecções por Coronavirus/virologia , Genes Reporter , Células HEK293 , Humanos , Células Jurkat , Luciferases/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Fatores de Transcrição NFATC/genética , Receptores de IgG/genética , Receptores de IgG/imunologia , Elementos de Resposta , Glicoproteína da Espícula de Coronavírus/metabolismo , Transfecção
5.
Nat Commun ; 11(1): 5128, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046695

RESUMO

The impact of SARS-CoV-2 infection during gestation remains unclear. Here, we analyse the viral genome on maternal and newborns nasopharyngeal swabs, vaginal swabs, maternal and umbilical cord plasma, placenta and umbilical cord biopsies, amniotic fluids and milk from 31 mothers with SARS-CoV-2 infection. In addition, we also test specific anti-SARS-CoV-2 antibodies and expression of genes involved in inflammatory responses in placentas, and in maternal and umbilical cord plasma. We detect SARS-CoV-2 genome in one umbilical cord blood and in two at-term placentas, in one vaginal mucosa and in one milk specimen. Furthermore, we report the presence of specific anti-SARS-CoV-2 IgM and IgG antibodies in one umbilical cord blood and in one milk specimen. Finally, in the three documented cases of vertical transmission, SARS-CoV-2 infection was accompanied by a strong inflammatory response. Together, these data support the hypothesis that in utero SARS-CoV-2 vertical transmission, while low, is possible. These results might help defining proper obstetric management of COVID-19 pregnant women, or putative indications for mode and timing of delivery.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Transmissão Vertical de Doença Infecciosa , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Complicações Infecciosas na Gravidez/virologia , Adolescente , Adulto , Anticorpos Antivirais/análise , Betacoronavirus/genética , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/patologia , Feminino , Genoma Viral , Humanos , Recém-Nascido , Inflamação , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/patologia , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/patologia , Adulto Jovem
8.
PLoS Pathog ; 16(9): e1008817, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32970782

RESUMO

There is a clear requirement for an accurate SARS-CoV-2 antibody test, both as a complement to existing diagnostic capabilities and for determining community seroprevalence. We therefore evaluated the performance of a variety of antibody testing technologies and their potential use as diagnostic tools. Highly specific in-house ELISAs were developed for the detection of anti-spike (S), -receptor binding domain (RBD) and -nucleocapsid (N) antibodies and used for the cross-comparison of ten commercial serological assays-a chemiluminescence-based platform, two ELISAs and seven colloidal gold lateral flow immunoassays (LFIAs)-on an identical panel of 110 SARS-CoV-2-positive samples and 50 pre-pandemic negatives. There was a wide variation in the performance of the different platforms, with specificity ranging from 82% to 100%, and overall sensitivity from 60.9% to 87.3%. However, the head-to-head comparison of multiple sero-diagnostic assays on identical sample sets revealed that performance is highly dependent on the time of sampling, with sensitivities of over 95% seen in several tests when assessing samples from more than 20 days post onset of symptoms. Furthermore, these analyses identified clear outlying samples that were negative in all tests, but were later shown to be from individuals with mildest disease presentation. Rigorous comparison of antibody testing platforms will inform the deployment of point-of-care technologies in healthcare settings and their use in the monitoring of SARS-CoV-2 infections.


Assuntos
Anticorpos Antivirais/análise , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Testes Sorológicos/métodos , Adulto , Idoso , Betacoronavirus , Técnicas de Laboratório Clínico , Serviços de Saúde Comunitária , Ensaio de Imunoadsorção Enzimática , Feminino , Hospitais , Humanos , Imunoensaio , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia
10.
Acta Biomed ; 91(3): e2020016, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32921712

RESUMO

The paper wants to present the data of infection of the Health Care Workers of a research and teaching hospital in Milan, Italy. The majority (2554, 55.9%) of 4572 HCWs were tested for SARS-CoV-2 and 8.8% were found positive. Most of the tested workers were women, but we found higher relative frequency of positivity for men, even after adjustment for age, working area, and occupation. The higher frequency of positive tests in the medicine area is probably explained by the higher concentration in that area of COVID-19 patients. Conversely, the low frequency of positive HCWs in intensive care units is  probably explained by the diffuse and continuous use of PPD. Our results show that HCWs in a research and teaching hospital in the most hit Region in Italy had a similar pattern of infection as all other HCWs all over the world. The problem of SARS-CoV-2 infections among the hospital personnel HCWs should remind us  the concerns about hospital acquired infections both for patients and HCWs.


Assuntos
Anticorpos Antivirais/análise , Betacoronavirus/imunologia , Infecções por Coronavirus/transmissão , Infecção Hospitalar/epidemiologia , Pessoal de Saúde/estatística & dados numéricos , Hospitais de Ensino/estatística & dados numéricos , Pneumonia Viral/transmissão , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/epidemiologia
11.
Acta Biomed ; 91(3): e2020024, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32921720

RESUMO

Coronavirus disease (COVID-19) is a systemic disease which can cause multiple organ failure and death primarly due to vascular endothelium injury. Severe acute respiratory distress syndrome (ARDS) is the main cause of death: its management and treatment should be tailored to the individual COVID-19 patient's phenotype. Early diagnosis of COVID-19 is paramount for disease treatment and infection control. Naso-pharyngeal (NP) swab is commonly used as screening and diagnostic tool for COVID-19, but in some cases it can be resulted negative even in presence of clinical and epidemiological criteria, and typical radiological and laboratory findings of COVID-19, as we have observed. Here we report our experience in the first month of the Italian epidemic. We strongly recommend clinicians to maintain a high index of suspicion for COVID-19, regardless of the persistence negativity of NP swabs, and not to delay the initiation of therapy in presence of typical clinical, radiological and laboratory findings of COVID-19.


Assuntos
Anticorpos Antivirais/análise , Betacoronavirus/imunologia , Infecções por Coronavirus/diagnóstico , Serviço Hospitalar de Emergência/estatística & dados numéricos , Nasofaringe/virologia , Pandemias , Pneumonia Viral/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Humanos , Itália/epidemiologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Fatores de Tempo
12.
Biosens Bioelectron ; 169: 112604, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32980805

RESUMO

Virus severely endangers human life and health, and the detection of viruses is essential for the prevention and treatment of associated diseases. Metal-organic framework (MOF), a novel hybrid porous material which is bridged by the metal clusters and organic linkers, has become a promising biosensor platform for virus detection due to its outstanding properties including high surface area, adjustable pore size, easy modification, etc. However, the MOF-based sensing platforms for virus detection are rarely summarized. This review systematically divided the detection platforms into nucleic acid and immunological (antigen and antibody) detection, and the underlying sensing mechanisms were interpreted. The nucleic acid sensing was discussed based on the properties of MOF (such as metal ion, functional group, geometry structure, size, porosity, stability, etc.), revealing the relationship between the sensing performance and properties of MOF. Moreover, antibodies sensing based on the fluorescence detection and antigens sensing based on molecular imprinting or electrochemical immunoassay were highlighted. Furthermore, the remaining challenges and future development of MOF for virus detection were further discussed and proposed. This review will provide valuable references for the construction of sophisticated sensing platform for the detection of viruses, especially the 2019 coronavirus.


Assuntos
Técnicas Biossensoriais/métodos , Estruturas Metalorgânicas/química , Viroses/virologia , Vírus/isolamento & purificação , Animais , Anticorpos Antivirais/análise , Antígenos Virais/análise , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Humanos , Imunoensaio/instrumentação , Imunoensaio/métodos , Modelos Moleculares , Impressão Molecular/instrumentação , Impressão Molecular/métodos , Ácidos Nucleicos/análise , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Viroses/diagnóstico
13.
Am J Case Rep ; 21: e925931, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32980852

RESUMO

BACKGROUND The worldwide spread of the severe acute respiratory syndrome-coronavirus-2 (SARS-COV-2) has created unprecedented situations for healthcare professionals and healthcare systems. Although infection with this virus is considered the main health problem currently, other diseases are still prevalent. CASE REPORT This report describes a 59-year-old man who presented with symptoms of dyspnea and fever that were attributed to Covid-19 infection. His clinical condition deteriorated and further examinations revealed a subjacent severe aortic regurgitation due to acute infective endocarditis. Surgical treatment was successful. CONCLUSIONS The results of diagnostic tests for Covid-19 should be re-evaluated whenever there are clinical mismatches or doubts, as false-positive Covid-19 test results can occur. Clinical interpretation should not be determined exclusively by the Covid-19 pandemic. This case report highlights the importance of using validated and approved serological and molecular testing to detect infection with SARS-CoV-2, and to repeat tests when there is doubt about presenting symptoms.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Diagnóstico Tardio , Endocardite/complicações , Endocardite/diagnóstico , Pneumonia Viral/diagnóstico , Anticorpos Antivirais/análise , Insuficiência da Valva Aórtica/complicações , Insuficiência da Valva Aórtica/diagnóstico , Procedimentos Cirúrgicos Cardíacos/métodos , Infecções por Coronavirus/complicações , Estado Terminal , Progressão da Doença , Dispneia/diagnóstico , Dispneia/etiologia , Endocardite/virologia , Reações Falso-Positivas , Febre/diagnóstico , Febre/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Medição de Risco , Resultado do Tratamento
14.
Arch Iran Med ; 23(9): 629-632, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32979911

RESUMO

BACKGROUND: The Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epidemic broke out in December 2019 and is now characterized as a pandemic. Effective control of this infectious disease requires access to diagnostic techniques, for both case finding and epidemic size estimation. The molecular technique is routinely used worldwide. Although it is the "standard" case detection and management method, it has its own shortcomings. Thus, some easy-to-use rapid serological tests have been developed. METHODS: One hundred and fourteen positive RT-PCR-diagnosed patients were tested by VivaDiag Kit, a brand of rapid serological kits available in hospitals affiliated to Tehran University of Medical Sciences (TUMS), Tehran, Iran. Frozen serum specimens taken from healthy people in summer and fall 2019 were also tested as negative controls. RESULTS: Test sensitivity was 47.9% (95% confidence interval [CI]: 38.8-56.9) for IgM and 47.0% (95% CI: 38.0-56.0) for IgG. There was no difference between IgG and IgM seropositivity except in one case. Specificity was calculated as 99.0% (95% CI: 96.4-99.9) for IgM and of 100.0% (95% CI: 0.98.2-100.0) for IgG. Sensitivity was higher in men and older participants. CONCLUSION: This test can be used for epidemiological investigations, especially for the estimation of the level of infection in the community, after it is properly corrected for sensitivity and specificity. The low sensitivity could be attributed to the technical limitations of the kit or low levels of antibodies after infection. The different sensitivity in age and sex groups supports the hypothesis that different people show different immune responses to this virus.


Assuntos
Anticorpos Antivirais/análise , Betacoronavirus/imunologia , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Testes Sorológicos/métodos , Adulto , Infecções por Coronavirus/epidemiologia , Feminino , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Masculino , Pandemias , Pneumonia Viral/epidemiologia
15.
BMC Infect Dis ; 20(1): 713, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993515

RESUMO

BACKGROUND: The clinical features, course and outcome of hantavirus infection is highly variable. Symptoms of the central nervous system may occur, but often present atypically and diagnostically challenging. Even though the incidence of hantavirus infection is increasing worldwide, this case is the first to describe diabetes insipidus centralis as a complication of hantavirus infection in the Western world. CASE PRESENTATION: A 49-year old male presenting with severe headache, nausea and photophobia to our neurology department was diagnosed with acute haemorrhage in the pituitary gland by magnetic resonance imaging. In the following days, the patient developed severe oliguric acute kidney failure. Diagnostic workup revealed a hantavirus infection, so that the pituitary haemorrhage resulting in hypopituitarism was seen as a consequence of hantavirus-induced hypophysitis. Under hormone replacement and symptomatic therapy, the patient's condition and kidney function improved considerably, but significant polyuria persisted, which was initially attributed to recovery from kidney injury. However, water deprivation test revealed central diabetes insipidus, indicating involvement of the posterior pituitary gland. The amount of urine production normalized with desmopressin substitution. CONCLUSION: Our case report highlights that neurological complications of hantavirus infection should be considered in patients with atypical clinical presentation.


Assuntos
Diabetes Insípido Neurogênico/etiologia , Infecções por Hantavirus/complicações , Hantavirus/genética , Hantavirus/imunologia , Hipofisite/etiologia , Hipopituitarismo/etiologia , Poliúria/etiologia , Lesão Renal Aguda/tratamento farmacológico , Anticorpos Antivirais/análise , Antidiuréticos/uso terapêutico , Desamino Arginina Vasopressina/uso terapêutico , Diabetes Insípido Neurogênico/tratamento farmacológico , Seguimentos , Infecções por Hantavirus/virologia , Terapia de Reposição Hormonal , Humanos , Hipofisite/diagnóstico por imagem , Hipofisite/tratamento farmacológico , Hipopituitarismo/diagnóstico por imagem , Hipopituitarismo/tratamento farmacológico , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Filogenia , Reação em Cadeia da Polimerase , Poliúria/tratamento farmacológico , Resultado do Tratamento
16.
Int Breastfeed J ; 15(1): 68, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32762723

RESUMO

BACKGROUND: In China, mothers with confirmed or suspected COVID-19 pneumonia are recommended to stop breastfeeding. However, the evidence to support this guidance is lacking. There have been relatively few cases reported about direct breastfeeding an infant by a mother with SARS-CoV-2 pneumonia. Therefore, it is necessary to assess the safety of breastfeeding and the possible protective effects of breast milk on infants. CASE PRESENTATION: This report analyzes the case of a mother who continued breastfeeding her 13 month-old child when both were diagnosed with confirmed COVID-19 pneumonia. We describe the clinical presentation, diagnosis, treatment, and outcome. The presence of SARS-CoV-2 nucleic acid was determined in maternal serum, breast milk, nasopharyngeal (NP) swabs and feces, and in infant serum, NP swabs and feces. IgM and IgG antibodies against SARS-CoV-2 were assessed in maternal serum and breast milk and in infant serum. SARS-CoV-2 nucleic acid was not detected in the breast milk, and antibodies against SARS-CoV-2 were detected in the mother's serum and milk. CONCLUSIONS: The present case further confirms that the possibility of mother-to-child transmission about SARS-CoV-2 via breast milk alone was very small, and breast milk is safe for direct feeding of infants.


Assuntos
Anticorpos Antivirais/análise , Betacoronavirus/isolamento & purificação , Aleitamento Materno , Infecções por Coronavirus/transmissão , Leite Humano/virologia , Pneumonia Viral/transmissão , Infecções por Coronavirus/prevenção & controle , Feminino , Humanos , Lactente , Transmissão Vertical de Doença Infecciosa , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle
17.
JCI Insight ; 5(18)2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32796155

RESUMO

Evaluation of potential immunity against the novel severe acute respiratory syndrome (SARS) coronavirus that emerged in 2019 (SARS-CoV-2) is essential for health, as well as social and economic recovery. Generation of antibody response to SARS-CoV-2 (seroconversion) may inform on acquired immunity from prior exposure, and antibodies against the SARS-CoV-2 spike protein receptor binding domain (S-RBD) are speculated to neutralize virus infection. Some serology assays rely solely on SARS-CoV-2 nucleocapsid protein (N-protein) as the antibody detection antigen; however, whether such immune responses correlate with S-RBD response and COVID-19 immunity remains unknown. Here, we generated a quantitative serological ELISA using recombinant S-RBD and N-protein for the detection of circulating antibodies in 138 serial serum samples from 30 reverse transcription PCR-confirmed, SARS-CoV-2-hospitalized patients, as well as 464 healthy and non-COVID-19 serum samples that were collected between June 2017 and June 2020. Quantitative detection of IgG antibodies against the 2 different viral proteins showed a moderate correlation. Antibodies against N-protein were detected at a rate of 3.6% in healthy and non-COVID-19 sera collected during the pandemic in 2020, whereas 1.9% of these sera were positive for S-RBD. Approximately 86% of individuals positive for S-RBD-binding antibodies exhibited neutralizing capacity, but only 74% of N-protein-positive individuals exhibited neutralizing capacity. Collectively, our studies show that detection of N-protein-binding antibodies does not always correlate with presence of S-RBD-neutralizing antibodies and caution against the extensive use of N-protein-based serology testing for determination of potential COVID-19 immunity.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Betacoronavirus/fisiologia , Infecções por Coronavirus , Nucleocapsídeo/imunologia , Pandemias , Pneumonia Viral , Glicoproteína da Espícula de Coronavírus/imunologia , Imunidade Adaptativa/imunologia , Anticorpos Neutralizantes/análise , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Pneumonia Viral/imunologia , Pneumonia Viral/terapia , Pneumonia Viral/virologia , Ligação Proteica , Sensibilidade e Especificidade , Soroconversão , Testes Sorológicos/métodos
19.
PLoS One ; 15(8): e0238068, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841290

RESUMO

Newcastle Disease (ND) is a viral disease spread worldwide with a high impact on economy and animal welfare. Vaccination against Newcastle Disease is one of the main control measures in countries such as Germany with endemic occurrence of Newcastle Disease virus in the free ranging bird population. The German Standing Veterinary Committee on Immunization (StIKo Vet) recommends to revaccinate chickens at intervals of six weeks against Newcastle Disease with attenuated live vaccines via drinking water or spray in line with the SPCs (Summary of Product Characteristics) of current vaccines. However, it is still common practice to revaccinate only every twelve weeks because the SPCs of former vaccines proposed a revaccination after checking the antibody titer which based on practical knowledge was typically sufficient for twelve weeks. The aim of this study was to evaluate if a vaccination interval of twelve weeks against Newcastle Disease under field conditions results in sufficient seroconversion to protect flocks. Antibody titers of 810 blood samples from 27 backyard flocks of chickens were analyzed by ELISA- and HI-tests between 69 and 111 days after vaccination of the flocks with attenuated live vaccines of the ND strain Clone 30. Furthermore, data on the flocks such as breed, sex and age were collected through a questionnaire. In this study a sufficient antibody titer was found in 26 of these flocks. Therefore, a vaccination interval of every twelve weeks with the live vaccines tested is suitable for a vaccination protocol against Newcastle Disease. The lack of seroconversion of one flock also emphasizes the need for regular vaccination monitoring by serological testing and re-evaluation of the vaccination process if needed.


Assuntos
Anticorpos Antivirais/análise , Galinhas/imunologia , Galinhas/virologia , Doença de Newcastle/prevenção & controle , Vacinação/métodos , Animais , Alemanha , Fatores de Tempo
20.
J Med Microbiol ; 69(9): 1183-1196, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32812860

RESUMO

Introduction. PCV2 is a DNA virus that exists widely in pigs and has caused great economic losses to the pig industry worldwide. In the existing commercial PCV2 enzyme-linked immunosorbent assay (ELISA) kits both natural infection with PCV2 and vaccine immunization produce results that are positive for PCV2 Cap antibodies and therefore they cannot diagnose PCV2 infection in immunized pig farms.Aim. To establish a PCV2 non-structural protein antibody detection method that distinguishes between antibodies resulting from natural prior exposure (infection) and those induced by subunit vaccine immunization.Methodology. Based on the non-structural Rep' protein, we established an indirect ELISA (iELISA) using sera from guinea pigs and piglets.Results. The results for iELISA for guinea pig serum showed that animals vaccinated with a whole-virus inactivated PCV2 vaccine had 100 % (10/10) Cap antibody positivity and 100 % (10/10) Rep' antibody positivity. Guinea pigs vaccinated with a recombinant subunit PCV2 vaccine had 100 % (10/10) Cap antibody positivity, while no (0/10) guinea pigs were Rep' antibody-positive. The combined detection results for the Rep' iELISA and a PCV2 Antibody Test kit (Commercial) showed that pigs vaccinated with a whole-virus inactivated PCV2 vaccine or PCV2 SD/2017 had 100 % (5/5) Cap antibody positivity and 100 % (5/5) Rep' antibody positivity. Pigs vaccinated with a recombinant subunit PCV2 vaccine had 100 % (5/5) Cap antibody positivity, while no (0/10) pigs were Rep' antibody-positive.Conclusion. This paper describes an effective iELISA method that can distinguish natural infection with PCV2 (Cap and Rep positive) or inoculation with a whole-virus inactivated vaccine (Cap and Rep positive) from subunit vaccine immunization (Cap-positive, Rep-negative). These comparative assays could be very useful in the control of PCV2 in pig herds.


Assuntos
Anticorpos Antivirais/imunologia , Infecções por Circoviridae/sangue , Infecções por Circoviridae/veterinária , Circovirus/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Doenças dos Suínos/sangue , Proteínas Virais/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/análise , Infecções por Circoviridae/imunologia , Circovirus/genética , Imunização , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Vacinas de Subunidades/administração & dosagem , Vacinas de Subunidades/genética , Vacinas de Subunidades/imunologia , Proteínas Virais/administração & dosagem , Proteínas Virais/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
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