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1.
PLoS One ; 17(1): e0262162, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34982806

RESUMO

Analysis of convalescent plasma derived from individuals has shown that IgG3 has the most important role in binding to SARS-CoV-2 antigens; however, this has not yet been confirmed in large studies, and the link between binding and neutralization has not been confirmed. By analyzing plasma pools consisting of 247-567 individual convalescent donors, we demonstrated the binding of IgG3 and IgM to Spike-1 protein and the receptor-binding domain correlates strongly with viral neutralization in vitro. Furthermore, despite accounting for only approximately 12% of total immunoglobulin mass, collectively IgG3 and IgM account for approximately 80% of the total neutralization. This may have important implications for the development of potent therapies for COVID-19, as it indicates that hyperimmune globulins or convalescent plasma donations with high IgG3 concentrations may be a highly efficacious therapy.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/sangue , COVID-19/imunologia , Convalescença , Imunoglobulina G/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Chlorocebus aethiops , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , SARS-CoV-2/fisiologia , Células Vero
2.
BMC Res Notes ; 15(1): 16, 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35016699

RESUMO

OBJECTIVE: To ensure the health of newborns, it is necessary to perform high-quality diagnostic tests. The TORCH panel is a set of tests that identifies infectious pathogens such as Toxoplasma (Toxo) and Cytomegalovirus (CMV) that are common in low-setting populations. We performed TORCH panel quality planning using six sigma in a reference laboratory at Peru. RESULTS: This was a cross-sectional study. TORCH tests include Toxo, Rubella, CMV, and Herpes. We processed all samples by fourth-generation ELISA on the GEMINI XCR200 analyzer (Diatron, Budapest, Hungary). We obtained the imprecision from the annual data of the external quality assessment plan and we used the CLSI EP12-A3 guideline. In a total of 44,788 analyses, the average imprecision was 3.69 ± 1.47%, and CMV had lower imprecision (2.3 and 2.6% for IgM and IgG, respectively). Quality planning of the TORCH panel allowed estimating the sigma value that ranged from 4 to 10 (average 7 ± 2 sigma), where rubella had the highest values (10 for IgM and 8 for IgG) while HSV2 had the lowest values (4 for IgM and 5 for IgG). Our results suggest the optimal performance of half of the markers including Toxoplasma, Rubella, and CMV in the Peruvian population.


Assuntos
Complicações Infecciosas na Gravidez , Rubéola (Sarampo Alemão) , Toxoplasma , Toxoplasmose , Estudos Transversais , Feminino , Humanos , Imunoglobulina M , Recém-Nascido , Peru , Gravidez , Rubéola (Sarampo Alemão)/diagnóstico , Gestão da Qualidade Total
3.
BMC Infect Dis ; 22(1): 35, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991519

RESUMO

BACKGROUND: Reactivation of latent Toxoplasma gondii (T. gondii) infection is more common than primary infection in patients with human immunodeficiency virus (HIV). We report a rare case of primary T. gondii infection-associated hemophagocytic syndrome (HPS). CASE PRESENTATION: A man with HIV infection presented with fever, dyspnea and pancytopenia. He was diagnosed with primary T. gondii infection by the seroconversion from single-positive IgM antibody to double-positive IgM and IgG antibody. Metagenomic next-generation sequencing (mNGS) of a plasma sample yielded high reads of T. gondii DNA. He responded well to combined anti-Toxoplasma medicines and glucocorticoid treatment. CONCLUSIONS: In patients with HPS and positive T. gondii IgM antibody, mNGS analysis of a peripheral blood sample is helpful in diagnosing disseminated T. gondii infection. The dynamic changes by serological detection for IgM and IgG of T. gondii further supported the inference that the patient has experienced a primary T. gondii infection.


Assuntos
Infecções por HIV , Linfo-Histiocitose Hemofagocítica , Toxoplasma , Toxoplasmose , Anticorpos Antiprotozoários , Infecções por HIV/complicações , Humanos , Imunoglobulina M , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/tratamento farmacológico , Masculino , Estudos Soroepidemiológicos , Toxoplasma/genética , Toxoplasmose/complicações , Toxoplasmose/diagnóstico , Toxoplasmose/tratamento farmacológico
4.
BMC Infect Dis ; 22(1): 19, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983410

RESUMO

BACKGROUND: Up to now, epidemiological studies on the prevalence of Toxoplasma gondii infection among drug addicted individuals have been rarely performed. By designing an age and sex matched case-control study, we sought to determine the prevalence and associated factors with T. gondii infection in these population using serological and molecular techniques. METHODS: One hundred and thirty-seven drug addicted individuals and 141 healthy subjects were enrolled in this study. Informed consent as well as a standard questionnaire were obtained from all subjects participating. Blood samples were collected from each participant and the serum was screened for anti-Toxoplasma antibodies (IgG and IgM). PCR assay was performed using the primer pair targeting the RE and GRA6 genes of T. gondii. Then, PCR products were sequenced to determine genotype. RESULTS: The seroprevalence of T. gondii infection based on IgG titer was 34.3% in case and 9.9% in the control groups, revealing a statistically significant difference (OR = 4.37; 95% CI = 2.46-9.12; P = 0.001). After analyzing the variables studied through the questionnaire, age was the only significantly factor associated with the anti-T. gondii IgG antibody in case group. Considering PCR assays with RE genomic target, the prevalence of T. gondii infection was 5.1% in the case and 3.5% in control groups which the difference was no statistically significant (OR = 1.46; 95% CI = 0.45-4.73; P = 0.521). Subsequently, all sequenced samples were genotype #1 using the GRA6 genomic target. CONCLUSIONS: T. gondii exposure is relatively high among drug addicted individuals in Iran, and there is a need for health policymakers and researchers to establish enlightenment and prevention programs for these population at risk of infection.


Assuntos
Preparações Farmacêuticas , Toxoplasma , Toxoplasmose , Anticorpos Antiprotozoários , Estudos de Casos e Controles , Humanos , Imunoglobulina G , Imunoglobulina M , Fatores de Risco , Estudos Soroepidemiológicos , Inquéritos e Questionários , Toxoplasma/genética , Toxoplasmose/epidemiologia
5.
BMC Infect Dis ; 22(1): 21, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983411

RESUMO

BACKGROUND: In symptomatic patients, the diagnostic approach of COVID-19 should be holistic. We aimed to evaluate the concordance between RT-PCR and serological tests (IgM/IgG), and identify the factors that best predict mortality (clinical stages or viral load). METHODS: The study included 242 patients referred to the University hospital of Kinshasa for suspected COVID-19, dyspnea or ARDS between June 1st, 2020 and August 02, 2020. Both antibody-SARS-CoV2 IgM/IgG and RT-PCR method were performed on the day of admission to hospital. The clinical stages were established according to the COVID-19 WHO classification. The viral load was expressed by the CtN2 (cycle threshold value of the nucleoproteins) and the CtE (envelope) genes of SARS- CoV-2 detected using GeneXpert. Kappa test and Cox regression were used as appropriate. RESULTS: The GeneXpert was positive in 74 patients (30.6%). Seventy two patients (29.8%) had positive IgM and 34 patients (14.0%) had positive IgG. The combination of RT-PCR and serological tests made it possible to treat 104 patients as having COVID-19, which represented an increase in cases of around 41% compared to the result based on GeneXpert alone. The comparison between the two tests has shown that 57 patients (23.5%) had discordant results. The Kappa coefficient was 0.451 (p < 0.001). We recorded 23 deaths (22.1%) among the COVID-19 patients vs 8 deaths (5.8%) among other patients. The severe-critical clinical stage increased the risk of mortality vs. mild-moderate stage (aHR: 26.8, p < 0.001). The values of CtE and CtN2 did not influence mortality significantly. CONCLUSION: In symptomatic patients, serological tests are a support which makes it possible to refer patients to the dedicated COVID-19 units and treat a greater number of COVID-19 patients. WHO Clinical classification seems to predict mortality better than SARS-Cov2 viral load.


Assuntos
COVID-19 , RNA Viral , Anticorpos Antivirais , República Democrática do Congo/epidemiologia , Humanos , Imunoglobulina M , SARS-CoV-2 , Testes Sorológicos
6.
BMC Infect Dis ; 22(1): 10, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983429

RESUMO

BACKGROUND: Serosurveillance is crucial in estimating the range of SARS-CoV-2 infections, predicting the possibility of another wave, and deciding on a vaccination strategy. To understand the herd immunity after the COVID-19 pandemic, the seroprevalence was measured in 3062 individuals with or without COVID-19 from the clinic. METHODS: The levels of SARS-CoV-2 antibody IgM and IgG were measured by the immuno-colloidal gold method. A fusion fragment of nucleocapsid and spike protein was detected by a qualitative test kit with sensitivity (89%) and specificity (98%). RESULTS: The seroprevalence rate for IgM and IgG in all outpatients was 2.81% and 7.51%, respectively. The sex-related prevalence rate of IgG was significantly higher (P < 0.05) in women than men. The highest positive rate of IgM was observed in individuals < 20 years of age (3.57%), while the highest seroprevalence for IgG was observed in persons > 60 years of age (8.61%). Positive rates of IgM and IgG in the convalescent patients were 31.82% and 77.27%, respectively, which was significantly higher than individuals with suspected syndromes or individuals without any clinical signs (P < 0.01). Seroprevalence for IgG in medical staff was markedly higher than those in residents. No significant difference of seroprevalence was found among patients with different comorbidities (P > 0.05). CONCLUSIONS: The low positive rate of the SARS-CoV-2 IgM and nucleic acid (NA) test indicated that the SARS-CoV-2 outbreak is subsiding after 3 months, and the possibility of reintroduction of the virus from an unidentified natural reservoir is low. Seroprevalence provides information for humoral immunity and vaccine in the future.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Controle de Doenças Transmissíveis , Feminino , Humanos , Imunoglobulina G , Imunoglobulina M , Masculino , Pandemias , Estudos Soroepidemiológicos
7.
Methods Mol Biol ; 2414: 341-362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34784045

RESUMO

Complement is a key component of functional immunological assays used to evaluate vaccine-mediated immunity to a range of bacterial and viral pathogens. However, standardization of these assays is complicated due to the availability of a human complement source that lacks existing antibodies acquired either through vaccination or natural circulation of the pathogen of interest. We have developed a method for depleting both IgG and IgM in 200 mL batches from pooled hirudin-derived human plasma by sequential affinity chromatography using a Protein G Sepharose column followed by POROS™ CaptureSelect™ IgM Affinity resin. The production of large IgG- and IgM-depleted batches of human plasma that retains total hemolytic and alternative pathway activities allows for improved assay standardization and comparison of immune responses in large clinical trials.


Assuntos
Proteínas do Sistema Complemento/imunologia , Cromatografia de Afinidade , Humanos , Imunoglobulina G , Imunoglobulina M
8.
Int J Pharm ; 612: 121365, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-34896215

RESUMO

PEGylation increases the circulation time of the nanocarrier, but also triggers accelerated blood clearance (ABC) phenomenon. It is well-known that the ABC phenomenon results in shortened blood circulation and aberrant increase in liver and spleen accumulation, which greatly limits the application of PEGylated nano-preparations. For many years, researchers have been working hard to find ways to reduce or eliminate the ABC phenomenon. Previous studies have focused on PEG molecular weight and PEG alternative materials, but there has never been any research on the effect of different PEG chain types on the ABC phenomenon. Therefore, 40 kDa molecular weight of linear PEG lipid derivatives (DSPE-mPEG40k) and branched PEG lipid derivatives (DSPE-mPEG2,40k) were selected to modify nanoemulsions to explore the influence of distinct PEG chain types on avoiding the ABC phenomenon for the first time. We pioneer the use of linear and branched PEG lipid derivatives (DSPE-mPEG40k and DSPE-mPEG2,40k) to modify nanoemulsions (PE40k and PE2,40k). Upon characterization, PE40k and PE2,40k showed good physicochemical properties in the aspect of size, polydispersity index (PDI value), and zeta potential. Surprisingly, the pharmacokinetics study indicated that repeated injection of PE40k and PE2,40k did not trigger the ABC phenomenon. More importantly, PE2,40k possessed a long circulation time and did not cause ABC phenomenon after repeated injection. This may be attributed to the fact that PE2,40k induced noticeably lower anti-PEG IgM levels compared to linear PEG-modified nanocarriers and did not activate the complement system. Therefore, we speculate that DSPE-mPEG2,40k-modified nanocarriers possess promising prospects in avoiding the ABC phenomenon, which may improve the possibility of wide application of nanoformulations.


Assuntos
Lipossomos , Polietilenoglicóis , Imunoglobulina M , Lipídeos , Peso Molecular , Baço
9.
J Infect Chemother ; 28(1): 112-115, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34548238

RESUMO

OBJECTIVES: This study aimed to explore the seasonal and regional features of cat-scratch disease (CSD) based on 15-years of test results for anti-Bartonella henselae IgG and IgM by immunofluorescence assay (IFA) performed as a laboratory specialized in diagnostic testing of CSD in Japan. A literature search was performed to put our findings in perspective. METHODS: A total of 956 sera from patients suspected of CSD were submitted to our laboratory from nationwide. Seasonal changes in the monthly positive rates of IgG/IgM antibodies and regional distribution of the test specimens were analyzed. RESULTS: The monthly positive rates of anti-B. henselae IFA of IgG and IgM were both significantly high between September and January and low between March and July. The seasonal pattern observed in this study was similar to the ones reported from US and France, which were analyzed from a clinical database (monthly incidence of CSD diagnosis) or from monthly positive rates of either B. henselae PCR or anti-B. henselae IFA. However, fluctuations in the IFA monthly positive rates in this study were more pronounced than other reports. Regarding regionality, the test specimens submitted to us for IFA were prominently more from southwestern areas than from northern/middle-northern areas of Japan. The distribution coincided well with the regional distribution of CSD case reports and with a known regional prevalence of Bartonella-species bacteremia among pet cats in Japan. CONCLUSION: These epidemiological features in Japan are of relevance in the clinical diagnoses of CSD.


Assuntos
Bartonella henselae , Doença da Arranhadura de Gato , Anticorpos Antibacterianos , Doença da Arranhadura de Gato/diagnóstico , Doença da Arranhadura de Gato/epidemiologia , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G , Imunoglobulina M , Japão/epidemiologia , Estações do Ano
11.
J Med Virol ; 94(1): 335-341, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34524695

RESUMO

Fully automated immunoassays for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies that are strongly correlated with neutralization antibodies (nAbs) are clinically important because they enable the assessment of humoral immunity after infection and vaccination. Access SARS-CoV-2 immunoglobulin M (IgM) and immunoglobulin G (IgG) II antibody tests are semi-quantitative, fully automated immunoassays that detect anti-receptor-binding domain (RBD) antibodies and might reflect nAb levels in coronavirus disease 2019 (COVID-19). However, no studies have investigated the clinical utility of these tests in association with nAbs to date. To evaluate the clinical utility of Access SARS-CoV-2 IgM and IgG II antibody tests and their correlation with the SARS-CoV-2 surrogate virus neutralization test (sVNT) that measures nAbs in patients with COVID-19, we analyzed 54 convalescent serum samples from COVID-19 patients and 89 serum samples from non-COVID-19 patients. The presence of anti-RBD antibodies was detected using Access SARS-CoV-2 IgM and IgG II antibody tests, while nAbs were measured by sVNT. The sensitivity and specificity of sVNT were 94.4% and 98.9%, respectively. There were strong positive correlations between the inhibition values of sVNT and the results of the Access SARS-CoV-2 IgM (R = 0.95, R2 = 0.90, p < 0.001) and IgG II antibody tests (R = 0.96, R2 = 0.92, p < 0.001). In terms of the presence of nAbs, the sensitivity and specificity were 98.1% and 98.9% in the IgM assay and 100.0% and 100.0% in the IgG II assay, respectively. The Access SARS-CoV-2 IgM and IgG II antibody tests showed high sensitivity and specificity for the detection of nAbs in COVID-19 patients and might be alternatives for measuring nAbs.


Assuntos
Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Imunoensaio/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , SARS-CoV-2/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Neutralização/métodos , Sensibilidade e Especificidade
12.
Clin Chim Acta ; 525: 6-11, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34896061

RESUMO

BACKGROUND: Concomitant presence of lupus anticoagulant (LA) and monoclonal immunoglobulin in the same patient is uncommon and the influence of this finding on coagulation results is still unknown. CASE REPORT: We present a patient with a diagnosis of systemic lupus erythematosus (SLE) and secondary antiphospholipid syndrome (APS) with permanently positive LA who presented with accidental finding of newly discovered monoclonal IgM in a high concentration and dramatically prolonged prothrombin time (PT) and activated partial thromboplastin time (aPTT), without bleeding manifestations. CONCLUSION: Concomitant presence of extremely prolonged PT and aPTT with unusual coagulation reaction kinetics, consistent LA ratio over the follow-up period and normalization of coagulation screening results with decreasing monoclonal IgM concentration elicited suspicion that PT and aPTT prolongation could be attributed to M-protein with antiphospholipid specificity. Low LA-sensitive aPTT reagent Actin FS demonstrated exceptional sensitivity, whereas human placental thromboplastin in contrast to recombinant reagents showed significantly lower sensitivity to monoclonal IgM with antiphospholipid specificity. Changes in the activity of SLE observed during the follow-up period were inversely related to monoclonal IgM concentration, while the presence of secondary APS was consistent. Described analytical interference on PT and aPTT without bleeding manifestation should point towards suspicion of previously unidentified monoclonal IgM with antiphospholipid sensitivity.


Assuntos
Síndrome Antifosfolipídica , Lúpus Eritematoso Sistêmico , Síndrome Antifosfolipídica/diagnóstico , Testes de Coagulação Sanguínea , Feminino , Humanos , Imunoglobulina M , Inibidor de Coagulação do Lúpus , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Placenta , Gravidez
13.
Methods Mol Biol ; 2409: 173-196, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34709642

RESUMO

A reliable and specific diagnosis is imperative in viral diagnosis, both for clinical management and surveillance, and to ensure that early treatment and control measures are carried out. The number of days of illness is important to choose the most appropriate method to be used and for the correct interpretation of the results obtained. Specific IgM is elicited after that period, indicating an active infection and usually lasts up to 3 months. However, in DENV secondary infections, IgM levels may be significantly lower or undetectable. After 10-12 days, a lifetime specific IgG is produced. Routinely, the laboratory diagnosis of DENV infections can be performed by viral isolation and/or detection of viral nucleic acid, serological assays for the detection of specific antibodies (IgM/IgG), antigen (NS1) and the detection of viral antigens in tissues, which are suitable during certain phases of the disease. For serological diagnosis, serum, plasma, or cerebrospinal fluid (CSF) samples may be investigated. If the test is carried out a few days after collection, the specimens can be stored at 4 °C, since the immunoglobulins are stable in serum or plasma. If the storage period is extended, the material must be kept at -20 °C or -70 °C. In serology, several methods can be used to detect specific viral antigens and/or antibodies, produced by the host in response to DENV infection. Routinely, serological tests include the hemagglutination inhibition (HI) assay, the plaque reduction neutralizing test (PRNT), the gold standard assay for dengue immune response characterization, and ELISAs to detect IgM (MAC-ELISA) and IgG (IgG-ELISA).


Assuntos
Vírus da Dengue , Dengue , Anticorpos Antivirais , Antígenos Virais , Dengue/diagnóstico , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G , Imunoglobulina M , Sensibilidade e Especificidade , Proteínas não Estruturais Virais
14.
Biosens Bioelectron ; 197: 113762, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34773750

RESUMO

The COVID-19 pandemic has resulted in a worldwide health crisis. Rapid diagnosis, new therapeutics and effective vaccines will all be required to stop the spread of COVID-19. Quantitative evaluation of serum antibody levels against the SARS-CoV-2 virus provides a means of monitoring a patient's immune response to a natural viral infection or vaccination, as well as evidence of a prior infection. In this paper, a portable and low-cost electrochemical immunosensor is developed for the rapid and accurate quantification of SARS-CoV-2 serum antibodies. The immunosensor is capable of quantifying the concentrations of immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies against the SARS-CoV-2 spike protein in human serum. For IgG and IgM, it provides measurements in the range of 10.1 ng/mL - 60 µg/mL and 1.64 ng/mL - 50 µg/mL, respectively, both with an assay time of 13 min. We also developed device stabilization and storage strategies to achieve stable performance of the immunosensor over 24-week storage at room temperature. We evaluated the performance of the immunosensor using COVID-19 patient serum samples collected at different time points after symptom onset. The rapid and sensitive detection of IgG and IgM provided by our immunosensor fulfills the need of rapid COVID-19 serological testing for both point-of-care diagnosis and population immunity screening.


Assuntos
Técnicas Biossensoriais , COVID-19 , Anticorpos Antivirais , Teste Sorológico para COVID-19 , Humanos , Imunoensaio , Imunoglobulina M , Pandemias , SARS-CoV-2 , Sensibilidade e Especificidade , Glicoproteína da Espícula de Coronavírus
15.
J Clin Virol ; 146: 105052, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34920374

RESUMO

BACKGROUND: Antibody detection of SARS-CoV-2 requires an understanding of its variation, course, and duration. METHODS: Antibody response to SARS-CoV-2 was evaluated over 5-430 days on 828 samples across COVID-19 severity levels, for total antibody (TAb), IgG, IgA, IgM, neutralizing antibody (NAb), antibody avidity, and for receptor-binding-domain (RBD), spike (S), or nucleoprotein (N). Specificity was determined on 676 pre-pandemic samples. RESULTS: Sensitivity at 30-60 days post symptom onset (pso) for TAb-S/RBD, TAb-N, IgG-S, IgG-N, IgA-S, IgM-RBD, and NAb was 96.6%, 99.5%, 89.7%, 94.3%, 80.9%, 76.9% and 92.8%, respectively. Follow-up 430 days pso revealed: TAb-S/RBD increased slightly (100.0%); TAb-N decreased slightly (97.1%); IgG-S and IgA-S decreased moderately (81.4%, 65.7%); NAb remained positive (94.3%), slightly decreasing in activity after 300 days; there was correlation with IgG-S (Rs = 0.88) and IgA-S (Rs = 0.71); IgG-N decreased significantly from day 120 (15.7%); IgM-RBD dropped after 30-60 days (22.9%). High antibody avidity developed against S/RBD steadily with time in 94.3% of patients after 430 days. This correlated with persistent antibody detection depending on antibody-binding efficiency of the test design. Severe COVID-19 correlated with earlier and higher antibody response, mild COVID-19 was heterogeneous with a wide range of antibody reactivities. Specificity of the tests was ≥99%, except for IgA (96%). CONCLUSION: Sensitivity of anti-SARS-CoV-2 assays was determined by test design, target antigen, antibody avidity, and COVID-19 severity. Sustained antibody detection was mainly determined by avidity progression for RBD and S. Testing by TAb and for S/RBD provided the highest sensitivity and longest detection duration of 14 months so far.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Neutralizantes , Anticorpos Antivirais , Formação de Anticorpos , Humanos , Imunoglobulina G , Imunoglobulina M , Cinética , Glicoproteína da Espícula de Coronavírus
16.
Emerg Microbes Infect ; 11(1): 227-239, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34931940

RESUMO

Dengue is caused by four genetically distinct viral serotypes, dengue virus (DENV) 1-4. Following transmission by Aedes mosquitoes, DENV can cause a broad spectrum of clinically apparent disease ranging from febrile illness to dengue hemorrhagic fever and dengue shock syndrome. Progress in the understanding of different dengue serotypes and their impacts on specific host-virus interactions has been hampered by the scarcity of tools that adequately reflect their antigenic and genetic diversity. To bridge this gap, we created and characterized infectious clones of DENV1-4 originating from South America, Africa, and Southeast Asia. Analysis of whole viral genome sequences of five DENV isolates from each of the four serotypes confirmed their broad genetic and antigenic diversity. Using a modified circular polymerase extension reaction (CPER), we generated de novo viruses from these isolates. The resultant clones replicated robustly in human and insect cells at levels similar to those of the parental strains. To investigate in vivo properties of these genetically diverse isolates, representative viruses from each DENV serotype were administered to NOD Rag1-/-, IL2rgnull Flk2-/- (NRGF) mice, engrafted with components of a human immune system. All DENV strains tested resulted in viremia in humanized mice and induced cellular and IgM immune responses. Collectively, we describe here a workflow for rapidly generating de novo infectious clones of DENV - and conceivably other RNA viruses. The infectious clones described here are a valuable resource for reverse genetic studies and for characterizing host responses to DENV in vitro and in vivo.


Assuntos
Vírus da Dengue/genética , Vírus da Dengue/imunologia , Dengue/virologia , Aedes/fisiologia , Aedes/virologia , Animais , Anticorpos Antivirais/imunologia , Variação Antigênica , Dengue/genética , Dengue/imunologia , Dengue/transmissão , Vírus da Dengue/classificação , Vírus da Dengue/isolamento & purificação , Variação Genética , Humanos , Imunoglobulina M/imunologia , Camundongos , Camundongos Knockout , Genética Reversa , Sorogrupo
18.
Rev Bras Ginecol Obstet ; 43(12): 887-893, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34933381

RESUMO

OBJECTIVE: The purpose of the present study is to standardize and evaluate the use of the immunoglobulin G (IgG) antibody avidity test on blood samples from newborns collected on filter paper to perform the heel test aiming at its implementation in ongoing programs. METHODS: Blood samples from newborns were collected on filter paper simultaneously with the heel prick test. All samples were subjected to immunoglobulin M IgM and IgG enzyme-linked immunosorbent assays (ELISA). Peripheral blood was collected again in the traditional way and on filter paper from newborns with high IgG levels (33). Three types of techniques were performed, the standard for measuring IgG in serum, adapted for filter paper and the technique of IgG avidity in serum and on filter paper. The results of the avidity test were classified according to the Rahbari protocol. RESULTS: Among the 177 samples, 17 were collected in duplicate from the same child, 1 of peripheral blood and 1 on filter paper. In this analysis, 1 (5.88%) of the 17 samples collected in duplicate also exhibited low IgG avidity, suggesting congenital infection. In addition, the results obtained from serum and filter paper were in agreement, that is, 16 (94.12%) samples presented high avidity, with 100% agreement between the results obtained from serum and from filter paper. CONCLUSION: The results of the present study indicate that the avidity test may be another valuable method for the diagnosis of congenital toxoplasmosis in newborns.


Assuntos
Imunoglobulina G , Toxoplasma , Toxoplasmose Congênita , Anticorpos Antiprotozoários , Diagnóstico Precoce , Humanos , Imunoglobulina M , Recém-Nascido , Toxoplasmose Congênita/diagnóstico
19.
Rev. baiana saúde pública ; 45(Supl. Especial 2): 48-57, 2021/12/28.
Artigo em Português | LILACS | ID: biblio-1352325

RESUMO

A rabdomiólise como complicação da dengue é subnotificada e pouco descrita na literatura. O presente caso traz um alerta para recordar tal possibilidade, principalmente devido à alta incidência da dengue no Brasil e da importância do manejo inicial, que pode evitar um desfecho desfavorável. Este relato trata de um paciente de 54 anos que iniciou com quadro agudo de fraqueza, com dor intensa em membros inferiores, dor abdominal, náuseas, vômitos e anúria. Foi observada evidente disfunção renal aguda em urgência dialítica com acidose metabólica grave, além de hiperuricemia, hiponatremia, hipocalcemia e hipercalemia, com valores de creatinofosfoquinase (CPK) de 125.010 e de mioglobina, 318,28. O paciente necessitou de três sessões de hemodiálise e recebeu alta com recuperação da função renal. O resultado da sorologia IgM para dengue foi positivo após um mês e dez dias da admissão hospitalar.


Reports on rhabdomyolysis as a complication of dengue are scarce in the literature. This study warns about such a possibility, especially considering the high incidence of dengue in Brazil and the importance of early management to avoid an unfavorable outcome for the patient. The case consists of a 54-year-old patient admitted to the hospital with complains of acute weakness, severe lower limb pain, abdominal pain, nausea, vomiting, and anuria. Clinical evaluation indicated acute renal dysfunction in dialysis emergency with severe metabolic acidosis, as well as hyperuricemia, hyponatremia, hypocalcemia, and hyperkalemia, with creatine phosphokinase (CPK) values equal to 125.010 and myoglobin to 318.28. The patient was discharged with recovery of renal function after three hemodialysis sessions. Serology results were positive for dengue IgM one month and ten days after hospital admission.


La rabdomiólisis como complicación del dengue está poco implementada en la literatura y poco reportada, y este caso trae una advertencia para recordar esta posibilidad, principalmente por la alta incidencia del dengue en el país en el que vivimos y la importancia del manejo inicial, evitando un desfavorable resultado para el paciente. Se trata de un paciente de 54 años que inicia debilidad aguda, dolor severo en miembros inferiores, dolor abdominal, náuseas, vómitos y anuria. Se evidenció disfunción renal aguda en urgencia de diálisis con acidosis metabólica severa, además de hiperuricemia, hiponatremia, hipocalcemia e hiperpotasemia, con valores de creatinfosfoquinasa (CPK)de 125.010 y mioglobina de 318,28. El paciente requirió tres sesiones de hemodiálisis y fue dado de alta con recuperación de la función renal. El resultado de la serología IgM para el dengue fue positivoun mes y diez días después del ingreso hospitalario.


Assuntos
Rabdomiólise , Imunoglobulina M , Recuperação de Função Fisiológica , Dengue , Diálise
20.
Viruses ; 13(12)2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34960822

RESUMO

A microarray-based assay to detect IgG and IgM antibodies against betacoronaviruses (SARS-CoV-2, SARS, MERS, OC43, and HKU1), other respiratory viruses and type I interferons (IFN-Is) was developed. This multiplex assay was applied to track antibody cross-reactivity due to previous contact with similar viruses and to identify antibodies against IFN-Is as the markers for severe COVID-19. In total, 278 serum samples from convalescent plasma donors, COVID-19 patients in the intensive care unit (ICU) and patients who recovered from mild/moderate COVID-19, vaccine recipients, prepandemic and pandemic patients with autoimmune endocrine disorders, and a heterogeneous prepandemic cohort including healthy individuals and chronically ill patients were analyzed. The anti-SARS-CoV-2 microarray results agreed well with the ELISA results. Regarding ICU patients, autoantibodies against IFN-Is were detected in 10.5% of samples, and 10.5% of samples were found to simultaneously contain IgM antibodies against more than two different viruses. Cross-reactivity between IgG against the SARS-CoV-2 nucleocapsid and IgG against the OC43 and HKU1 spike proteins was observed, resulting in positive signals for the SARS-CoV-2 nucleocapsid in prepandemic samples from patients with autoimmune endocrine disorders. The presence of IgG against the SARS-CoV-2 nucleocapsid in the absence of IgG against the SARS-CoV-2 spike RBD should be interpreted with caution.


Assuntos
Anticorpos Antivirais/imunologia , Interferon Tipo I/imunologia , SARS-CoV-2/imunologia , Vírus/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , COVID-19/imunologia , Teste Sorológico para COVID-19 , Reações Cruzadas , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Análise Serial de Proteínas , Doenças Respiratórias/imunologia , Doenças Respiratórias/virologia , Vírus/classificação
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