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1.
Sci Rep ; 11(1): 17381, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34462453

RESUMO

Cancer patients are more susceptible to SARS-CoV-2 infection and generally have higher mortality rate. Anti-SARS-CoV-2 IgG is an important consideration for the patients in this COVID-19 pandemic. Recent researches suggested the rapid decay of anti-SARS-CoV-2 antibodies in the general population, but the decline rate of the antibodies in cancer patients was unknown. In this observational study, we reported the clinical features of the 53 cancer patients infected by SARS-CoV-2 from Wuhan, China and tracked the presence of anti-SARS-CoV-2 antibodies in the patients for more than 12 months. We found the duration (days) of anti-SARS-CoV-2 IgG in the patients was significant longer in chemotherapy (mean: 175; range: 75 to 315) and radiotherapy groups (mean: 168; range: 85 to 265) than in non-chemo- or radio-therapy group (mean: 58; range: 21 to 123) after their recovery from COVID-19. We also used single-cell RNA sequencing to track the immunologic changes in a representative patient recovered  from COVID-19 and found that CD8 + effective T cells, memory B cells and plasma cells were persistently activated in the patient undergoing chemotherapy. Together, our findings show that chemotherapy and radiotherapy might be beneficial to extend the duration of anti-SARS-CoV-2 IgG.


Assuntos
COVID-19/sangue , Imunoglobulina G/análise , Neoplasias/imunologia , Neoplasias/virologia , SARS-CoV-2/imunologia , Adulto , Idoso , Anticorpos Antivirais/análise , Linfócitos B/metabolismo , Linfócitos T CD8-Positivos/metabolismo , COVID-19/imunologia , China , Tratamento Farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neoplasias/radioterapia , Plasmócitos/metabolismo , Radioterapia , SARS-CoV-2/genética , Análise de Sequência de RNA , Análise de Célula Única , Fatores de Tempo
2.
Sci Rep ; 11(1): 17325, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-34462501

RESUMO

Two-dose messenger RNA vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are highly effective in preventing symptomatic COVID-19 infection. However, the durability of protection is not known, nor is the effectiveness against emerging viral variants. Additionally, vaccine responses may differ based on prior SARS-CoV-2 exposure history. To investigate protection against SARS-CoV-2 variants we measured binding and neutralizing antibody responses following both vaccine doses. We document significant declines in antibody levels three months post-vaccination, and reduced neutralization of emerging variants, highlighting the need to identify correlates of clinical protection to inform the timing of and indications for booster vaccination.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Neutralizantes/análise , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Vacinas Sintéticas/administração & dosagem , Adulto , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/análise , Anticorpos Antivirais/metabolismo , COVID-19/imunologia , COVID-19/metabolismo , Teste de Ácido Nucleico para COVID-19 , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Feminino , Humanos , Imunoglobulina G/análise , Imunoglobulina G/metabolismo , Masculino , Pessoa de Meia-Idade , Glicoproteína da Espícula de Coronavírus/metabolismo , Fatores de Tempo , Vacinação , Vacinas Sintéticas/imunologia , Adulto Jovem
3.
FASEB J ; 35(9): e21862, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34416035

RESUMO

Loss of muscle mass and strength after disuse followed by impaired muscle recovery commonly occurs with aging. Metformin (MET) and leucine (LEU) individually have shown positive effects in skeletal muscle during atrophy conditions but have not been evaluated in combination nor tested as a remedy to enhance muscle recovery following disuse atrophy in aging. The purpose of this study was to determine if a dual treatment of metformin and leucine (MET + LEU) would prevent disuse-induced atrophy and/or promote muscle recovery in aged mice and if these muscle responses correspond to changes in satellite cells and collagen remodeling. Aged mice (22-24 months) underwent 14 days of hindlimb unloading (HU) followed by 7 or 14 days of reloading (7 or 14 days RL). MET, LEU, or MET + LEU was administered via drinking water and were compared to Vehicle (standard drinking water) and ambulatory baseline. We observed that during HU, MET + LEU resolved whole body grip strength and soleus muscle specific force decrements caused by HU. Gastrocnemius satellite cell abundance was increased with MET + LEU treatment but did not alter muscle size during disuse or recovery conditions. Moreover, MET + LEU treatment alleviated gastrocnemius collagen accumulation caused by HU and increased collagen turnover during 7 and 14 days RL driven by a decrease in collagen IV content. Transcriptional pathway analysis revealed that MET + LEU altered muscle hallmark pathways related to inflammation and myogenesis during HU. Together, the dual treatment of MET and LEU was able to increase muscle function, satellite cell content, and reduce collagen accumulation, thus improving muscle quality during disuse and recovery in aging.


Assuntos
Envelhecimento , Colágeno/metabolismo , Leucina/uso terapêutico , Metformina/uso terapêutico , Músculo Esquelético/efeitos dos fármacos , Atrofia Muscular/prevenção & controle , Células Satélites de Músculo Esquelético/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Fibrose/tratamento farmacológico , Elevação dos Membros Posteriores , Imunoglobulina G/análise , Leucina/farmacologia , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Desenvolvimento Muscular/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/citologia , Músculo Esquelético/patologia , Atrofia Muscular/patologia , Tamanho do Órgão/efeitos dos fármacos , RNA-Seq , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/patologia , Transdução de Sinais/efeitos dos fármacos
5.
Int J Nanomedicine ; 16: 4739-4753, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34267520

RESUMO

Background: Serological tests detecting severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are widely used in seroprevalence studies and evaluating the efficacy of the vaccination program. Some of the widely used serological testing techniques are enzyme-linked immune-sorbent assay (ELISA), chemiluminescence immunoassay (CLIA), and lateral flow immunoassay (LFIA). However, these tests are plagued with low sensitivity or specificity, time-consuming, labor-intensive, and expensive. We developed a serological test implementing flow-through dot-blot assay (FT-DBA) for SARS-CoV-2 specific IgG detection, which provides enhanced sensitivity and specificity while being quick to perform and easy to use. Methods: SARS-CoV-2 antigens were immobilized on nitrocellulose membrane to capture human IgG, which was then detected with anti-human IgG conjugated gold nanoparticle (hIgG-AuNP). A total of 181 samples were analyzed in-house. Within which 35 were further evaluated in US FDA-approved CLIA Elecsys SARS-CoV-2 assay. The positive panel consisted of RT-qPCR positive samples from patients with both <14 days and >14 days from the onset of clinical symptoms. The negative panel contained samples collected from the pre-pandemic era dengue patients and healthy donors during the pandemic. Moreover, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of FT-DBA were evaluated against RT-qPCR positive sera. However, the overall efficacies were assessed with sera that seroconverted against either nucleocapsid (NCP) or receptor-binding domain (RBD). Results: In-house ELISA selected a total of 81 true seropositive and 100 seronegative samples. The sensitivity of samples with <14 days using FT-DBA was 94.7%, increasing to 100% for samples >14 days. The overall detection sensitivity and specificity were 98.8% and 98%, respectively, whereas the overall PPV and NPV were 99.6% and 99%. Moreover, comparative analysis between in-house ELISA assays and FT-DBA revealed clinical agreement of Cohen's Kappa value of 0.944. The FT-DBA showed sensitivity and specificity of 100% when compared with commercial CLIA kits. Conclusion: The assay can confirm past SARS-CoV-2 infection with high accuracy within 2 minutes compared to commercial CLIA or in-house ELISA. It can help track SARS-CoV-2 disease progression, population screening, and vaccination response. The ease of use of the assay without requiring any instruments while being semi-quantitative provides the avenue of its implementation in remote areas around the globe, where conventional serodiagnosis is not feasible.


Assuntos
Ouro/química , Immunoblotting/métodos , Imunoglobulina G/análise , Nanopartículas Metálicas/química , Nucleocapsídeo/análise , SARS-CoV-2/isolamento & purificação , Adulto , Anticorpos Antivirais/sangue , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Valor Preditivo dos Testes , SARS-CoV-2/imunologia , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
6.
Sci Rep ; 11(1): 14893, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34290329

RESUMO

Comparing seroprevalence and antibody kinetics in three different commercially available assays for SARS-CoV-2. Serostatus of COVID-19 patients was analyzed 5 months and 10 months after their infection, using three different assays: Diasorin LIAISON, Euroimmun, Abbott Diagnostics ARCHITECT. Seropositivity at baseline differed significantly depending on the assay (Diasorin 81%, Euroimmun 83%, Abbott 59%). At follow-up antibody levels detected in the Diasorin assay were stable, while there was a significant loss in seropositivity in the Euroimmun and Abbott assays. There are significant differences in SARS-CoV-2 antibody kinetics based on the specific assay used.


Assuntos
Anticorpos Antivirais/análise , Teste para COVID-19/métodos , COVID-19/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , COVID-19/virologia , Criança , Pré-Escolar , Feminino , Alemanha/epidemiologia , Humanos , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
7.
Vector Borne Zoonotic Dis ; 21(8): 638-641, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34197265

RESUMO

Introduction: Many SARS-CoV-2 variants of concern (VOC) have been reported recently that were linked to increased transmission. In our earlier study using VOC 202012/01 (U.K. variant) and D614G variant in the hamster model, we observed higher viral RNA shedding through nasal wash in the case of U.K. variant with lower pathogenicity in lung. In this study, we have studied transmission of these two variants by direct contact, aerosol, and fomite routes in Syrian hamsters and compared the viral load and body weight changes in hamsters exposed by both variants to understand the transmission efficiency. Methods: Nasal, throat, and rectal swabs were collected sequentially to assess viral load till 14 days. Results: Transmission could be established by direct, aerosol, and fomite contact in Syrian hamsters. Body weight loss or viral load in the contact animals exposed did not show any statistical significance. Conclusion: The study demonstrated comparable transmission of both U.K. and D614G variants of SARS-CoV-2 in Syrian hamsters in the given conditions. Provided these data, it seems that all the routes of exposure are effective leading to higher transmission.


Assuntos
COVID-19/transmissão , COVID-19/virologia , SARS-CoV-2/classificação , Aerossóis , Animais , Cricetinae , Modelos Animais de Doenças , Fômites/virologia , Anticorpos Anti-HIV/análise , Imunoglobulina G/análise , Pulmão , Masculino , Mesocricetus , Cavidade Nasal/virologia , Faringe/virologia , RNA Viral/análise , Reto/virologia , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Reino Unido , Carga Viral , Perda de Peso
8.
PLoS One ; 16(7): e0251342, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34197468

RESUMO

Amperial™ is a novel assay platform that uses immobilized antigen in a conducting polymer gel followed by detection via electrochemical measurement of oxidation-reduction reaction between H2O2/Tetrametylbenzidine and peroxidase enzyme in a completed assay complex. A highly specific and sensitive assay was developed to quantify levels of IgG antibodies to SARS-CoV-2 in saliva. After establishing linearity and limit of detection we established a reference range of 5 standard deviations above the mean. There were no false positives in 667 consecutive saliva samples obtained prior to 2019. Saliva was obtained from 34 patients who had recovered from documented COVID-19 or had documented positive serologies. All of the patients with symptoms severe enough to seek medical attention had positive antibody tests and 88% overall had positive results. We obtained blinded paired saliva and plasma samples from 14 individuals. The plasma was analyzed using an EUA-FDA cleared ELISA kit and the saliva was analyzed by our Amperial™ assay. All 5 samples with negative plasma titers were negative in saliva testing. Eight of the 9 positive plasma samples were positive in saliva and 1 had borderline results. A CLIA validation was performed as a laboratory developed test in a high complexity laboratory. A quantitative non-invasive saliva based SARS-CoV-2 antibody test was developed and validated with sufficient specificity to be useful for population-based monitoring and monitoring of individuals following vaccination.


Assuntos
Anticorpos Antivirais/imunologia , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Saliva/imunologia , Anticorpos Antivirais/análise , COVID-19/imunologia , COVID-19/virologia , Técnicas Eletroquímicas/métodos , Humanos , Imunoglobulina G/análise , Limite de Detecção , SARS-CoV-2/isolamento & purificação , Saliva/virologia
10.
Ann Lab Med ; 41(6): 568-576, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34108284

RESUMO

Background: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is generally diagnosed by reverse transcription (RT)-PCR or serological assays. The SARS-CoV-2 viral load decreases a few days after symptom onset. Thus, the RT-PCR sensitivity peaks at three days after symptom onset (approximately 80%). We evaluated the performance of the ARCHITECT® SARS-CoV-2 IgG assay (henceforth termed IgG assay; Abbott Laboratories, Lake County, IL, USA), and the combination of RT-PCR and the IgG assay for COVID-19 diagnosis. Methods: In this retrospective study, 206 samples from 70 COVID-19 cases at two hospitals in Tokyo that were positive using RT-PCR were used to analyze the diagnostic sensitivity. RT-PCR-negative (N=166), COVID-19-unrelated (N=418), and Japanese Red Cross Society (N=100) samples were used to evaluate specificity. Results: Sensitivity increased daily after symptom onset and exceeded 84.4% after 10 days. Specificity ranged from 98.2% to 100% for samples from the three case groups. Seroconversion was confirmed from 9 to 20 days after symptom onset in 18 out of 32 COVID-19 cases with multiple samples and from another case with a positive result in the IgG assay for the first available sample. Conclusions: The combination of RT-PCR and IgG assay improves the robustness of laboratory diagnostics by compensating for the limitations of each method.


Assuntos
COVID-19/diagnóstico , Imunoglobulina G/análise , RNA Viral/análise , Anticorpos Antivirais/análise , COVID-19/virologia , Teste para COVID-19 , Humanos , Estudos Longitudinais , RNA Viral/metabolismo , Kit de Reagentes para Diagnóstico , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade
11.
Ann Lab Med ; 41(6): 577-587, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34108285

RESUMO

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody assays have high clinical utility in managing the pandemic. We compared antibody responses and seroconversion of coronavirus disease 2019 (COVID-19) patients using different immunoassays. Methods: We evaluated 12 commercial immunoassays, including three automated chemiluminescent immunoassays (Abbott, Roche, and Siemens), three enzyme immunoassays (Bio-Rad, Euroimmun, and Vircell), five lateral flow immunoassays (Boditech Med, SD biosensor, PCL, Sugentech, and Rapigen), and one surrogate neutralizing antibody assay (GenScript) in sequential samples from 49 COVID-19 patients and 10 seroconversion panels. Results: The positive percent agreement (PPA) of assays for a COVID-19 diagnosis ranged from 84.0% to 98.5% for all samples (>14 days after symptom onset), with IgM or IgA assays showing higher PPAs. Seroconversion responses varied across the assay type and disease severity. Assays targeting the spike or receptor-binding domain protein showed a tendency for early seroconversion detection and higher index values in patients with severe disease. Index values from SARS-CoV-2 binding antibody assays (three automated assays, one LFIA, and three EIAs) showed moderate to strong correlations with the neutralizing antibody percentage (r=0.517-0.874), and stronger correlations in patients with severe disease and in assays targeting spike protein. Agreement among the 12 assays was good (74.3%-96.4%) for detecting IgG or total antibodies. Conclusions: Positivity rates and seroconversion of SARS-CoV-2 antibodies vary depending on the assay kits, disease severity, and antigen target. This study contributes to a better understanding of antibody response in symptomatic COVID-19 patients using currently available assays.


Assuntos
Anticorpos Antivirais/análise , Teste para COVID-19/métodos , COVID-19/diagnóstico , SARS-CoV-2/imunologia , COVID-19/patologia , COVID-19/virologia , Humanos , Imunoensaio , Imunoglobulina A/análise , Imunoglobulina G/análise , Imunoglobulina M/análise , Kit de Reagentes para Diagnóstico , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade , Índice de Gravidade de Doença
12.
Hum Antibodies ; 29(3): 217-223, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34151783

RESUMO

BACKGROUND: As the extent of the pandemic and its seroprevalence pattern has been less clarified in pediatrics to date, we aimed to conduct this study to investigate the clinical and laboratory characteristics of COVID-19 in Iranian children, with a focus on evaluating the antibody prevalence and its relation with the laboratory tests. METHODS: All children with highly suspected COVID-19 were included. Anti-nucleoprotein SARS-CoV-2 were measured using SARS-CoV-2 immunoglobulin M (IgM) and SARS-CoV-2 IgG ELISA kits. Hypothesis testing was carried out through SPSS to unravel any association between the measurement tools and important clinical and laboratory characteristics. RESULTS: In this study, 254 patients were evaluated and 117 cases (46%) were male. The nucleic acid detection results for patient 55 were negative, but the IgM and IgG results were positive. Totally, 190 patients were tested for IgM in which only 14 (7.3%) had positive tests. Positive IgG was detected in 51 (20%) out of 254 patients; among them, 30 patients had negative SARS-CoV-2 RT-PCR (59%). Lower level of platelets in IgG positive group in comparison with the IgG negative group was observed (P value: 0.015). Moreover, higher alanine aminotransferase (ALT) was observed in the in IgG positive group (P value: 0.02). In patients with positive IgM, relative hypocalcemia (median of 8.25; IQR: 8.02-8.62) was found which appeared to be significant (P value: 0.02). CONCLUSION: This is the first largest study describing the SARS-CoV-2 seropositivity among children in Iran and provides important insight about the COVID-19 infection in children.


Assuntos
Anticorpos Antivirais/análise , Anticorpos Antivirais/imunologia , COVID-19/diagnóstico , COVID-19/imunologia , Hospitais , Pediatria , Encaminhamento e Consulta , SARS-CoV-2/imunologia , Adolescente , COVID-19/epidemiologia , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Imunoglobulina M/análise , Imunoglobulina M/imunologia , Lactente , Recém-Nascido , Irã (Geográfico)/epidemiologia , Masculino , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
13.
ACS Appl Mater Interfaces ; 13(23): 27645-27655, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34081862

RESUMO

A combined approach to signal enhancement in fluorescence affinity biosensors and assays is reported. It is based on the compaction of specifically captured target molecules at the sensor surface followed by optical probing with a tightly confined surface plasmon (SP) field. This concept is utilized by using a thermoresponsive hydrogel (HG) binding matrix that is prepared from a terpolymer derived from poly(N-isopropylacrylamide) (pNIPAAm) and attached to a metallic sensor surface. Epi-illumination fluorescence and SP-enhanced total internal reflection fluorescence readouts of affinity binding events are performed to spatially interrogate the fluorescent signal in the direction parallel and perpendicular to the sensor surface. The pNIPAAm-based HG binding matrix is arranged in arrays of sensing spots and employed for the specific detection of human IgG antibodies against the Epstein-Barr virus (EBV). The detection is performed in diluted human plasma or with isolated human IgG by using a set of peptide ligands mapping the epitope of the EBV nuclear antigen. Alkyne-terminated peptides were covalently coupled to the pNIPAAm-based HG carrying azide moieties. Importantly, using such low-molecular-weight ligands allowed preserving the thermoresponsive properties of the pNIPAAm-based architecture, which was not possible for amine coupling of regular antibodies that have a higher molecular weight.


Assuntos
Resinas Acrílicas/química , Técnicas Biossensoriais/métodos , Infecções por Vírus Epstein-Barr/diagnóstico , Antígenos Nucleares do Vírus Epstein-Barr/imunologia , Hidrogéis/química , Imunoglobulina G/análise , Fragmentos de Peptídeos/metabolismo , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/virologia , Fluorescência , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Hidrogéis/metabolismo , Imunoglobulina G/imunologia , Fragmentos de Peptídeos/imunologia , Polímeros/química
14.
PLoS One ; 16(6): e0252628, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34081747

RESUMO

Serological assessment of SARS-CoV-2 specific responses are an essential tool for determining the prevalence of past SARS-CoV-2 infections in the population especially when testing occurs after symptoms have developed and limited contact tracing is in place. The goal of our study was to test a new 10-plex electro-chemiluminescence-based assay to measure IgM and IgG responses to the spike proteins from multiple human coronaviruses including SARS-CoV-2, assess the epitope specificity of the SARS-CoV-2 antibody response against full-length spike protein, receptor-binding domain and N-terminal domain of the spike protein, and the nucleocapsid protein. We carried out the assay on samples collected from three sample groups: subjects diagnosed with COVID-19 from the U.S. Army hospital at Camp Humphreys in Pyeongtaek, South Korea; healthcare administrators from the same hospital but with no reported diagnosis of COVID-19; and pre-pandemic samples. We found that the new CoV-specific multiplex assay was highly sensitive allowing plasma samples to be diluted 1:30,000 with a robust signal. The reactivity of IgG responses to SARS-CoV-2 nucleocapsid protein and IgM responses to SARS-CoV-2 spike protein could distinguish COVID-19 samples from non-COVID-19 and pre-pandemic samples. The data from the three sample groups also revealed a unique pattern of cross-reactivity between SARS-CoV-2 and SARS-CoV-1, MERS-CoV, and seasonal coronaviruses HKU1 and OC43. Our findings show that the CoV-2 IgM response is highly specific while the CoV-2 IgG response is more cross-reactive across a range of human CoVs and also showed that IgM and IgG responses show distinct patterns of epitope specificity. In summary, this multiplex assay was able to distinguish samples by COVID-19 status and characterize distinct trends in terms of cross-reactivity and fine-specificity in antibody responses, underscoring its potential value in diagnostic or serosurveillance efforts.


Assuntos
Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Adulto , Anticorpos Antivirais/análise , Formação de Anticorpos , Reações Cruzadas , Feminino , Humanos , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Imunoglobulina M/análise , Imunoglobulina M/imunologia , Luminescência , Masculino , Pessoa de Meia-Idade , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Militares , Proteínas do Nucleocapsídeo/imunologia , Vírus da SARS/imunologia , SARS-CoV-2/patogenicidade , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus/imunologia , Estados Unidos
15.
PLoS Negl Trop Dis ; 15(5): e0009440, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34043621

RESUMO

BACKGROUND: Aedes mosquitoes are vectors for several major arboviruses of public health concern including dengue viruses. The relationships between Aedes infestation and disease transmission are complex wherein the epidemiological dynamics can be difficult to discern because of a lack of robust and sensitive indicators for predicting transmission risk. This study investigates the use of anti-Aedes saliva antibodies as a serological biomarker for Aedes mosquito bites to assess small scale variations in adult Aedes density and dengue virus (DENV) transmission risk in northeastern Thailand. Individual characteristics, behaviors/occupation and socio-demographics, climatic and epidemiological risk factors associated with human-mosquito exposure are also addressed. METHODS: The study was conducted within a randomized clustered control trial in Roi Et and Khon Kaen provinces over a consecutive 19 months period. Thirty-six (36) clusters were selected, each of ten houses. Serological and entomological surveys were conducted in all houses every four months and monthly in three sentinel households per cluster between September 2017 and April 2019 for blood spot collections and recording concurrent immature and adult Aedes indices. Additionally, the human exposure to Aedes mosquito bites (i.e., Mosquito Exposure Index or MEI) was estimated by ELISA measuring levels of human antibody response to the specific Nterm-34 kDa salivary antigen. The relationships between the MEI, vector infestation indices (adult and immature stages) and vector DENV infection were evaluated using a two-level (house and individual levels) mixed model analysis with one-month lag autoregressive correlation. RESULTS: There was a strong positive relationship between the MEI and adult Aedes (indoor and outdoor) density. Individuals from households with a medium mosquito density (mean difference: 0.091, p<0.001) and households with a high mosquito density (mean difference: 0.131, p<0.001) had higher MEI's compared to individuals from households without Aedes. On a similar trend, individuals from households with a low, medium or high indoor Aedes densities (mean difference: 0.021, p<0.007, 0.053, p<0.0001 and 0.037, p<0.0001 for low, medium and high levels of infestation, respectively) had higher MEI than individuals from houses without indoor Aedes. The MEI was driven by individual characteristics, such as gender, age and occupation/behaviors, and varied according to climatic, seasonal factors and vector control intervention (p<0.05). Nevertheless, the study did not demonstrate a clear correlation between MEI and the presence of DENV-infected Aedes. CONCLUSION: This study represents an important step toward the validation of the specific IgG response to the Aedes salivary peptide Nterm-34kDa as a proxy measure for Aedes infestation levels and human-mosquito exposure risk in a dengue endemic setting. The use of the IgG response to the Nterm-34 kDa peptide as a viable diagnostic tool for estimating dengue transmission requires further investigations and validation in other geographical and transmission settings.


Assuntos
Aedes/fisiologia , Aedes/virologia , Mordeduras e Picadas de Insetos/epidemiologia , Aedes/crescimento & desenvolvimento , Animais , Biomarcadores/sangue , Dengue/epidemiologia , Dengue/transmissão , Vírus da Dengue/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/análise , Mordeduras e Picadas de Insetos/imunologia , Masculino , Mosquitos Vetores/virologia , Saliva/imunologia , Tailândia/epidemiologia
16.
J Dairy Res ; 88(2): 189-193, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33952363

RESUMO

In this study it is hypothesized that there are differences between immunoglobulin G (IgG) content in colostrum from beef (Chianina, Podolica) and dairy (Holstein Friesian) cows and that variables such as breed, and parity can influence IgG content. The further objective was to determine if these factors may vary in terms of sensitivity, specificity and the cut point when data obtained with the digital Brix refractometer is compared with the gold standard radial immunodiffusion assay (RID). A total of 90 samples of first-milking colostrum were collected within 2 h after parturition. IgG concentration was determined indirectly by digital Brix refractometer and directly by RID. Results obtained by RID were compared among breed and parity. For the digital Brix refractometer, sensitivity and specificity to detect colostrum with an IgG concentration lower than 50 g/l were calculated and the optimal cut-point was selected for each breed. Samples containing less than <50 g/l IgG accounted for 15.9% of the total. Parity influenced colostral IgG concentration and beef cows had a higher mean concentration of IgG (101.1 g/l in Chianina and 90.6 g/l in Podolica) than dairy cows (71.1 g/l in Holstein Friesian) First parity Chianina cows had the highest IgG mean content (116.1 g/l). At the optimal cut-point for Brix refractometer (20%) sensitivity and specificity were 0.93 (0.84-0.97) and 0.81 (0.70-0.88), however, a breed-related cut-point could be used to reduce evaluation error. Linear regression modeling showed that refractometer data were related to RID (r = 0.78). Results obtained suggest that breed and parity can influence IgG content of colostrum and, despite the Brix refractometer being an excellent on-farm tool, a breed-based definition of optimal cut point is needed.


Assuntos
Bovinos/imunologia , Colostro/imunologia , Imunoglobulina G/análise , Refratometria/veterinária , Agricultura/métodos , Animais , Indústria de Laticínios/métodos , Feminino , Itália , Carne Vermelha , Refratometria/instrumentação , Sensibilidade e Especificidade
17.
Viruses ; 13(5)2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946311

RESUMO

With repeated positivity being an undiscovered and major concern, we aimed to evaluate which prognostic factors may impact repeated SARS-CoV-2 positivity (RSP) and their association with immunoglobulin detectability among recovered patients. A systematic literature search was performed on 5 April 2021. Cohort studies with risk factors for repeated RSP or information about the immunoglobulin response (immunoglobulin M (IgM) and/or immunoglobulin G (IgG)) were included in this analysis. The main examined risk factors were severity of the initial infection, body mass index (BMI), length of hospitalization (LOH), age, and gender, for which we pooled mean differences and odds ratios (ORs). Thirty-four cohort studies (N = 9269) were included in our analysis. We found that increased RSP rate might be associated with IgG positivity; IgG presence was higher in RSP patients (OR: 1.72, CI: 0.87-3.41, p = 0.117). Among the examined risk factors, only mild initial disease course showed a significant association with RSP (OR: 0.3, CI: 0.14-0.67, p = 0.003). Age, male gender, BMI, LOH, and severity of the first episode do not seem to be linked with repeated positivity. However, further prospective follow-up studies focusing on this topic are required.


Assuntos
Anticorpos Antivirais/análise , Teste Sorológico para COVID-19/métodos , COVID-19 , Imunoglobulina G/análise , Reinfecção , Fatores Etários , COVID-19/diagnóstico , COVID-19/imunologia , Humanos , Pandemias , Prognóstico , Reinfecção/diagnóstico , Reinfecção/imunologia , Fatores de Risco , Fatores Sexuais
18.
J Clin Neuromuscul Dis ; 22(4): 228-231, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34019009

RESUMO

ABSTRACT: Elsberg syndrome is a rare cause of lumbosacral radiculitis with concomitant thoracic and lumbosacral myelitis that can be seen after an acute or reactivated viral infection. After the initial coronavirus surge in New York City, a 68-year-old man developed progressive lower extremity weakness and a defined sensory level at the lower abdomen. He had highly elevated SARS-CoV-2 IgG antibodies despite an absence of preceding COVID-19 symptoms. Serial electrodiagnostic testing revealed absent lower extremity late responses, with otherwise normal distal sensorimotor conductions. Electromyography revealed active neurogenic changes and reduced motor unit recruitment in the L3-L4 myotomes. Treatment with methylprednisolone and intravenous immunoglobulin was followed by minimal clinical improvement but re-emergence of the lower extremity late responses on electrodiagnostic testing. We report here, to the best of our knowledge, the first case of suspected COVID-19-associated Elsberg syndrome, which expands the spectrum of neuromuscular manifestations associated with SARS-CoV-2 infection and sheds light on ways to approach diagnostic and treatment options for these patients.


Assuntos
COVID-19/complicações , Mielite/etiologia , Radiculopatia/etiologia , Idoso , Anti-Inflamatórios/uso terapêutico , Eletrodiagnóstico , Eletromiografia , Humanos , Imunoglobulina G/análise , Imageamento por Ressonância Magnética , Masculino , Metilprednisolona/uso terapêutico , Debilidade Muscular/etiologia , Mielite/diagnóstico , Condução Nervosa , Radiculopatia/diagnóstico , Coluna Vertebral/diagnóstico por imagem , Síndrome , Resultado do Tratamento
19.
Methods Mol Biol ; 2271: 23-45, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33907997

RESUMO

Intact mass analysis of proteins is simple, fast, and specific, and it effectively provides structural insight into the proteoforms or variants of the analyzed protein. For instance, the multiple glycoforms of recombinant monoclonal antibodies can be effectively analyzed by intact mass spectrometry (MS). A recent development in the Orbitrap technology has made this platform particularly well suited for analysis of large intact biomolecules, and here we describe procedures for performing intact mass analysis of intact glycoproteins using the Orbitrap platform, with the aim of identifying and quantitating the glycoforms. Emphasis is placed on the analysis of biopharmaceutical immunoglobulins (IgGs), but the procedures can be extended to other glycoproteins as needed.


Assuntos
Anticorpos Monoclonais/análise , Produtos Biológicos/análise , Glicoproteínas/análise , Imunoglobulina G/análise , Espectrometria de Massas , Processamento de Proteína Pós-Traducional , Cromatografia de Fase Reversa , Glicosilação , Proteínas Recombinantes/análise , Projetos de Pesquisa , Fluxo de Trabalho
20.
Methods Mol Biol ; 2271: 189-203, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33908009

RESUMO

Released N-glycan analysis using the fluorescent label 2-AB (2-aminobenzamide) has been the "gold standard" method for released glycan analysis for several years. The more recent RapiFluor-MS™ labeling technique, however, offers enhanced mass spectrometric detection of released N-glycans, improving the sensitivity and detection limits of the method. The optimized multidimensional detection offers increased confidence in glycan identification which can be further supported by an exoglycosidase digestion array (optional). Here we describe the PNGase F release of N-glycans from a typical IgG1 monoclonal antibody (mAb) with subsequent labeling with RapiFluor-MS™ for detection by HILIC-FLR-MS. The method output quantifies the relative proportion of each glycan species including core afucosylation, sialylation, and high-mannose content, and has a limit of detection (LOD) of 0.01% relative abundance.


Assuntos
Anticorpos Monoclonais/análise , Cromatografia Líquida de Alta Pressão , Corantes Fluorescentes/química , Glicoproteínas/análise , Imunoglobulina G/análise , Processamento de Proteína Pós-Traducional , Espectrometria de Massas por Ionização por Electrospray , Anticorpos Monoclonais/uso terapêutico , Fluorometria , Glicoproteínas/uso terapêutico , Glicosilação , Interações Hidrofóbicas e Hidrofílicas , Imunoglobulina G/uso terapêutico , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/metabolismo , Proteólise , Projetos de Pesquisa , Fluxo de Trabalho
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