scholarly journals Long-Term Longitudinal Evaluation of Six Commercial Immunoassays for the Detection of IgM and IgG Antibodies against SARS CoV-2

Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1244
Author(s):  
Iulia Nedelcu ◽  
Raluca Jipa ◽  
Roxana Vasilescu ◽  
Cristian Băicuș ◽  
Costin-Ioan Popescu ◽  
...  
Keyword(s):  
Clinical Performance ◽  
Sample Selection ◽  
Early Time ◽  
Humoral Response ◽  
High Specificity ◽  
Data Interpretation ◽  
Serum Samples ◽  
Chemiluminescent Immunoassay ◽  
Chemiluminescent Microparticle Immunoassay ◽  
Antibody Levels

The number of serological assays for SARS-CoV-2 has skyrocketed in the past year. Concerns have been raised regarding their performance characteristics, depending on the disease severity and the time of the analysis post-symptom onset (PSO). Thus, independent validations using an unbiased sample selection are required for meaningful serology data interpretation. We aimed to assess the clinical performance of six commercially available assays, the seroconversion, and the dynamics of the humoral response to SARS-CoV-2 infection. The study included 528 serum samples from 156 patients with follow-up visits up to six months PSO and 161 serum samples from healthy people. The IgG/total antibodies positive percentage increased and remained above 95% after six months when chemiluminescent immunoassay (CLIA) IgG antiS1/S2 and electro-chemiluminescent assay (ECLIA) total antiNP were used. At early time points PSO, chemiluminescent microparticle immunoassay (CMIA) IgM antiS achieved the best sensitivity. IgM and IgG appear simultaneously in most circumstances, and when performed in parallel the sensitivity increases. The severe and the moderate clinical forms were significantly associated with higher seropositivity percentage and antibody levels. High specificity was found in all evaluated assays, but the sensitivity was variable depending on the time PSO, severity of disease, detection method and targeted antigen.

scholarly journals Anti-SARS-CoV-2 IgG against the S Protein: A Comparison of BNT162b2, mRNA-1273, ChAdOx1 nCoV-2019 and Ad26.COV2.S Vaccines

Vaccines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 99
Author(s):  
Joanna Szczepanek ◽  
Monika Skorupa ◽  
Agnieszka Goroncy ◽  
Joanna Jarkiewicz-Tretyn ◽  
Aleksandra Wypych ◽  
...  
Keyword(s):  
Cellular Response ◽  
Protein A ◽  
Humoral Response ◽  
Blood Type ◽  
Vaccine Response ◽  
Serum Samples ◽  
Igg Antibody ◽  
Three Samples ◽  
Nicolaus Copernicus ◽  
Antibody Levels

Background: COVID-19 vaccines induce a differentiated humoral and cellular response, and one of the comparable parameters of the vaccine response is the determination of IgG antibodies. Materials and Methods: Concentrations of IgG anti-SARS-CoV-2 antibodies were analyzed at three time points (at the beginning of May, at the end of June and at the end of September). Serum samples were obtained from 954 employees of the Nicolaus Copernicus University in Toruń (a total of three samples each were obtained from 511 vaccinated participants). IgG antibody concentrations were determined by enzyme immunoassay. The statistical analysis included comparisons between vaccines, between convalescents and COVID-19 non-patients, between individual measurements and included the gender, age and blood groups of participants. Results: There were significant differences in antibody levels between mRNA and vector vaccines. People vaccinated with mRNA-1273 achieved the highest levels of antibodies, regardless of the time since full vaccination. People vaccinated with ChAdOx1 nCoV-2019 produced several times lower antibody levels compared to the mRNA vaccines, while the antibody levels were more stable. In the case of each of the vaccines, the factor having the strongest impact on the level and stability of the IgG antibody titers was previous SARS-CoV-2 infection. There were no significant correlations with age, gender and blood type. Summary: mRNA vaccines induce a stronger humoral response of the immune system with the fastest loss of antibodies over time.

scholarly journals Persistent Antibody Responses to SARS-CoV-2 Infection in Cancer Patients: A Single-Center Retrospective Observational Study

2021 ◽  
Vol 42 (02) ◽  
pp. 123-129
Author(s):  
Amit Agarwal ◽  
Saphalta Baghmar ◽  
Suhail Qureshi ◽  
Aseem Khurana ◽  
Rasika Setia ◽  
...  
Keyword(s):  
Cancer Patients ◽  
Seroconversion Rate ◽  
Age Groups ◽  
Humoral Response ◽  
Disease Status ◽  
Serum Samples ◽  
Cancer Disease ◽  
Care Workers ◽  
Antibody Levels ◽  
Roche Diagnostics

Abstract Introduction There is limited literature available regarding the prevalence and durability of immune response to infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)/coronavirus disease 2019 (COVID-19) in cancer patients. Objective The aim of this study was to analyze the seroconversion rate in cancer patients recovered from SARS-CoV-2 infection. Materials and Methods We retrospectively analyzed antibody levels and seroconversion rates in serum samples from 135 cancer patients who had recovered from SARS-CoV-2 infection. Chemiluminescent immunoassay using Roche Cobas e801 analyzer (Roche Diagnostics, Rotkreuz, Switzerland) was performed to identify Pan Ig antibody against nucleocapsid antigen. Reports of first, third, and sixth month were analyzed. Seroconversion was also compared with health-care workers (HCW) of our institute who had recovered from COVID-19 infection. Results Seroconversion rate in cancer patients was 81.2% at 1 month, 95% at 3 months, and 94.6% at 6 months post reverse transcriptase–polymerase chain reaction positivity. There was no difference in seroconversion rate among different age groups, gender, comorbidities, severity of COVID-19 symptoms, cancer disease status, and treatment with chemotherapy. Seroconversion rate in cancer patients is comparable to HCW (90.4 vs. 96%, p = 0.82) and is durable. Conclusion Humoral response to COVID-19 infection in cancer patients is comparable to general population and sustained. Such responses suggest that cancer patients are likely to benefit from COVID-19 vaccination.

scholarly journals A novel highly quantitative and reproducible assay for the detection of anti-SARS-CoV-2 IgG and IgM antibodies

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kenta Noda ◽  
Kouki Matsuda ◽  
Shigehiro Yagishita ◽  
Kenji Maeda ◽  
Yutaro Akiyama ◽  
...  
Keyword(s):  
Clinical Performance ◽  
High Sensitivity ◽  
Clinical Severity ◽  
Detection Accuracy ◽  
Serum Samples ◽  
Serological Tests ◽  
Nucleocapsid Proteins ◽  
Assay Performance ◽  
Quantification Accuracy ◽  
Antibody Levels

AbstractThe quantitative range and reproducibility of current serological tests for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are not optimized. Herein, we developed a diagnostic test that detects SARS-CoV-2 IgG and IgM with high quantitativeness and reproducibility and low interference. The system was based on the high-sensitivity chemiluminescence enzyme immunoassay (HISCL) platform and detects IgG and IgM specific to SARS-CoV-2 spike and nucleocapsid proteins. Quantification accuracy and reproducibility were evaluated using serially diluted samples from 60 SARS-CoV-2-infected patients. Assay performance was evaluated using serum samples from the SARS-CoV-2-infected patients and 500 SARS-CoV-2-negative serum samples collected before the emergence of SARS-CoV-2. The system showed high quantification accuracy (range, 102), high reproducibility (within 5%), and no cross-reaction between SARS1- and MERS-S proteins. Detection accuracy was 98.3% and 93.3% for IgG and IgM against spike proteins and 100% and 71.7% for IgG and IgM against nucleocapsid proteins, respectively. Mean antibody levels were > 10 times that in negative samples upon admission and > 100 times that at convalescent periods. Clinical severity upon admission was not correlated with IgG or IgM levels. This highly quantitative, reproducible assay system with high clinical performance may help analyze temporal serological/immunological profiles of SARS-CoV-2 infection and SARS-CoV-2 vaccine effectiveness.

scholarly journals Antibody Persistence 6 Months Post-Vaccination with BNT162b2 among Health Care Workers

Vaccines ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1125
Author(s):  
Flaminia Campo ◽  
Aldo Venuti ◽  
Fulvia Pimpinelli ◽  
Elva Abril ◽  
Giovanni Blandino ◽  
...  
Keyword(s):  
Health Care ◽  
Antibody Response ◽  
Health Care Workers ◽  
Geometric Mean ◽  
Serum Samples ◽  
Antibody Persistence ◽  
Care Workers ◽  
Open Debate ◽  
Chemiluminescent Immunoassay ◽  
Antibody Levels

Background: We present immunogenicity data 6 months after the first dose of BNT162b2 in correlation with age, gender, BMI, comorbidities and previous SARS-CoV-2 infection. Methods: An immunogenicity evaluation was carried out among health care workers (HCW) vaccinated at the Istituti Fisioterapici Ospitalieri (IFO). All HCW were asked to be vaccine by the national vaccine campaign at the beginning of 2021. Serum samples were collected on day 1 just prior to the first dose of the vaccine and on day 21 just prior to the second vaccination dose. Thereafter sera samples were collected 28, 49, 84 and 168 days after the first dose of BNT162b2. Quantitative measurement of IgG antibodies against S1/S2 antigens of SARS-CoV-2 was performed with a commercial chemiluminescent immunoassay. Results: Two hundred seventy-four HWCs were analyzed, 175 women (63.9%) and 99 men (36.1%). The maximum antibody geometric mean concentration (AbGMC) was reached at T2 (299.89 AU/mL; 95% CI: 263.53–339.52) with a significant increase compared to baseline (p < 0.0001). Thereafter, a progressive decrease was observed. At T5, a median decrease of 59.6% in COVID-19 negative, and of 67.8% in COVID-19 positive individuals were identified with respect to the highest antibody response. At T1, age and previous COVID-19 were associated with differences in antibody response, while at T2 and T3 differences in immune response were associated with age, gender and previous COVID-19. At T4 and T5, only COVID-19 positive participants demonstrated a greater antibody response, whereas no other variables seemed to influence antibody levels. Conclusions: Overall our study clearly shows antibody persistence at 6 months, albeit with a certain decline. Thus, the use of this vaccine in addressing the COVID-19 pandemic is supported by our results that in turn open debate about the need for further boosts.

scholarly journals SARS-CoV-2 Antibody Testing in Healthcare Workers: a comparison of the clinical performance of three commercially available antibody assays

2021 ◽  
Author(s):  
Niamh Allen ◽  
Melissa Brady ◽  
Antonio Isidro Carrion Martin ◽  
Lisa Domegan ◽  
Cathal Walsh ◽  
...  
Keyword(s):  
Clinical Performance ◽  
Natural Infection ◽  
Sample Selection ◽  
High Sensitivity ◽  
Population Based ◽  
Serological Response ◽  
Antibody Testing ◽  
Serum Samples ◽  
Entire Study ◽  
Asian Ethnicity

SARS-CoV-2 antibodies are an excellent indicator of past COVID-19 infection. As the COVID-19 pandemic progresses, retained sensitivity over time is an important quality in an antibody assay that is to be used for the purpose of population seroprevalence studies. We compared 5788 healthcare worker (HCW) serum samples on two serological assays (Abbott SARS-CoV-2 anti-nucleocapsid IgG and Roche Anti-SARS-CoV-2 anti-nucleocapsid Total Antibody) and a subset of samples (all Abbott assay positive or grayzone, n=485) on Wantai SARS-CoV-2 anti-spike Antibody ELISA. For 367 samples from HCW with previous PCR-confirmed SARS-CoV-2 infection we correlated the timing of infection with assay results. Overall seroprevalence was 4.2% on Abbott, 9.5% on Roche. Of those with previously confirmed infection, 41% (150/367) and 95% (348/367) tested positive on Abbott and Roche respectively. At 21 weeks (150 days) after confirmed infection, positivity on Abbott started to decline. Roche positivity was retained for the entire study period (33 weeks). Factors associated (P≤ 0.050) with Abbott seronegativity in those with previous PCR-confirmed infection included sex (male OR0.30;95%CI0.15-0.60), symptom severity (OR0.19 severe symptoms;95%CI0.05-0.61), ethnicity (OR0.28 Asian ethnicity;95%CI0.12-0.60) and time since PCR diagnosis (OR2.06 for infection 6 months previously;95%CI1.01-4.30. Wantai detected all previously confirmed infections. In our population, Roche detected antibodies up to at least seven months after natural infection with SARS-CoV-2. This may indicate that Roche is better suited than Abbott to population-based studies. Wantai demonstrated high sensitivity but sample selection was biased. The relationship between serological response and functional immunity to SARS-CoV-2 infection needs to be delineated.

scholarly journals Validation of Roche immunoassay for severe acute respiratory coronavirus 2 in South Africa

2021 ◽  
Vol 36 (1) ◽  
Author(s):  
Jurette S. Grove ◽  
Elizabeth S. Mayne ◽  
Wendy A. Burgers ◽  
Jonathan Blackburn ◽  
Sarika Jugwanth ◽  
...  
Keyword(s):  
High Specificity ◽  
Lower Sensitivity ◽  
Rt Pcr ◽  
Serum Samples ◽  
Time Points ◽  
Human Research Ethics ◽  
Chemiluminescent Immunoassay ◽  
Academic Laboratory ◽  
Negative Controls ◽  
Respiratory Coronavirus

Background: Serology testing is an important ancillary diagnostic to the reverse transcriptase polymerase chain reaction (RT-PCR) test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We aimed to evaluate the performance of the Roche Elecsys™ chemiluminescent immunoassay (Rotkreuz, Switzerland), that detects antibodies against the SARS-CoV-2 nucleocapsid antigen, at an academic laboratory in South Africa.Methods: Serum samples were collected from 312 donors with confirmed positive SARS-CoV-2 RT-PCR tests, with approval from a large university’s human research ethics committee. Negative controls included samples stored prior to December 2019 and from patients who tested negative for SARS-CoV-2 on RT-PCR and were confirmed negative using multiple serology methods (n = 124). Samples were stored at –80 °C and analysed on a Roche cobas™ 602 autoanalyser.Results: Compared with RT-PCR, our evaluation revealed a specificity of 100% and overall sensitivity of 65.1%. The sensitivity in individuals 14 days’ post-diagnosis was 72.6%, with the highest sensitivity 31–50 days’ post-diagnosis at 88.6%. Results were also compared with in-house serology tests that showed high agreement in majority of categories.Conclusions: The sensitivity at all-time points post-diagnosis was lower than reported in other studies, but sensitivity in appropriate cohorts approached 90% with a high specificity. The lower sensitivity at earlier time points or in individuals without symptomatology may indicate failure to produce antibodies, which was further supported by the comparison against in-house serology tests.

scholarly journals Cytomegalovirus antibody responses associated with increased risk of TB disease in Ugandan adults

2019 ◽  
Author(s):  
Lisa Stockdale ◽  
Stephen Nash ◽  
Ruth Farmer ◽  
John Raynes ◽  
Suresh Malikaarjun ◽  
...  
Keyword(s):  
Dose Response ◽  
Humoral Response ◽  
Serum Markers ◽  
Serum Samples ◽  
Markers Of Inflammation ◽  
Increased Risk ◽  
Specific Igg ◽  
Epstein Barr ◽  
Antibody Levels ◽  
Nested Case Control

Abstract Background Recent evidence highlights human cytomegalovirus (HCMV) and immune activation as risk factors for tuberculosis (TB) disease. It is not known whether other herpes viruses are also implicated, nor if a dose-response relationship exists between TB risk and herpes co-infection. Methods This nested case-control study used stored serum samples from 25 TB cases up to 10 years prior to TB diagnosis and between 3 and 6 matched non-TB controls from a rural Ugandan cohort. Samples were investigated for Epstein Barr (EBV), Herpes Simplex (HSV), and HCMV-specific IgG, serum markers of inflammation, and mycobacterial antibody levels. Results Humoral response to HCMV, but not EBV or HSV was associated with increased risk of active TB disease up to 10 years prior to diagnosis. Individuals with medium HCMV IgG were 2.8 times more likely to have TB (p=0.055), and those with high HCMV IgG 3.4 times more likely to have TB (p=0.007). Mycobacterial antibody levels were not associated with differences in odds of TB disease. IP-10 was independently associated with increased odds of TB; OR 4.2, p=0.009. Conclusions These data provide evidence of a dose response between magnitude of HCMV IgG with risk of TB disease. An inflammatory environment, characterized by serum IP-10 and IL1α, are independently associated with increased risk of TB disease.

scholarly journals Assessment of Gastrointestinal Autonomic Dysfunction: Present and Future Perspectives

2021 ◽  
Vol 10 (7) ◽  
pp. 1392
Author(s):  
Ditte S. Kornum ◽  
Astrid J. Terkelsen ◽  
Davide Bertoli ◽  
Mette W. Klinge ◽  
Katrine L. Høyer ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Autonomic Dysfunction ◽  
Physiological Function ◽  
Clinical Performance ◽  
Data Interpretation ◽  
Assessment Methods ◽  
Common Finding ◽  
Colonic Manometry ◽  
Target Organs ◽  
Common Causes

The autonomic nervous system delicately regulates the function of several target organs, including the gastrointestinal tract. Thus, nerve lesions or other nerve pathologies may cause autonomic dysfunction (AD). Some of the most common causes of AD are diabetes mellitus and α-synucleinopathies such as Parkinson’s disease. Widespread dysmotility throughout the gastrointestinal tract is a common finding in AD, but no commercially available method exists for direct verification of enteric dysfunction. Thus, assessing segmental enteric physiological function is recommended to aid diagnostics and guide treatment. Several established assessment methods exist, but disadvantages such as lack of standardization, exposure to radiation, advanced data interpretation, or high cost, limit their utility. Emerging methods, including high-resolution colonic manometry, 3D-transit, advanced imaging methods, analysis of gut biopsies, and microbiota, may all assist in the evaluation of gastroenteropathy related to AD. This review provides an overview of established and emerging assessment methods of physiological function within the gut and assessment methods of autonomic neuropathy outside the gut, especially in regards to clinical performance, strengths, and limitations for each method.

scholarly journals A longitudinal study of SARS-CoV-2-infected patients reveals a high correlation between neutralizing antibodies and COVID-19 severity

2021 ◽  
Author(s):  
Vincent Legros ◽  
Solène Denolly ◽  
Manon Vogrig ◽  
Bertrand Boson ◽  
Eglantine Siret ◽  
...  
Keyword(s):  
Intensive Care ◽  
Neutralizing Antibodies ◽  
Vaccine Development ◽  
Surface Protein ◽  
Humoral Response ◽  
Neutralizing Antibody ◽  
Rapid Decline ◽  
Serum Samples ◽  
Immune Correlates ◽  
Human Coronaviruses

AbstractUnderstanding the immune responses elicited by SARS-CoV-2 infection is critical in terms of protection against reinfection and, thus, for public health policy and vaccine development for COVID-19. In this study, using either live SARS-CoV-2 particles or retroviruses pseudotyped with the SARS-CoV-2 S viral surface protein (Spike), we studied the neutralizing antibody (nAb) response in serum samples from a cohort of 140 SARS-CoV-2 qPCR-confirmed infections, including patients with mild symptoms and also more severe forms, including those that required intensive care. We show that nAb titers correlated strongly with disease severity and with anti-spike IgG levels. Indeed, patients from intensive care units exhibited high nAb titers; conversely, patients with milder disease symptoms had heterogeneous nAb titers, and asymptomatic or exclusive outpatient-care patients had no or low nAbs. We found that nAb activity in SARS-CoV-2-infected patients displayed a relatively rapid decline after recovery compared to individuals infected with other coronaviruses. Moreover, we found an absence of cross-neutralization between endemic coronaviruses and SARS-CoV-2, indicating that previous infection by human coronaviruses may not generate protective nAbs against SARS-CoV-2. Finally, we found that the D614G mutation in the spike protein, which has recently been identified as the current major variant in Europe, does not allow neutralization escape. Altogether, our results contribute to our understanding of the immune correlates of SARS-CoV-2-induced disease, and rapid evaluation of the role of the humoral response in the pathogenesis of SARS-CoV-2 is warranted.

scholarly journals Serum MicroRNA Signature as a Diagnostic and Therapeutic Marker in Patients with Psoriatic Arthritis

2020 ◽  
Vol 47 (12) ◽  
pp. 1760-1767
Author(s):  
Sarah M. Wade ◽  
Trudy McGarry ◽  
Siobhan C. Wade ◽  
Ursula Fearon ◽  
Douglas J. Veale
Keyword(s):  
Psoriatic Arthritis ◽  
Characteristic Curve ◽  
High Specificity ◽  
Serum Samples ◽  
Rna Molecules ◽  
Serum Mirna ◽  
Serum Microrna ◽  
Specificity And Sensitivity ◽  
European League Against Rheumatism ◽  
Noninvasive Markers

ObjectiveMicroRNA (miRNA) are small endogenous regulatory RNA molecules that have emerged as potential therapeutic targets and biomarkers in autoimmunity. Here, we investigated serum miRNA levels in patients with psoriatic arthritis (PsA) and further assessed a serum miRNA signature in therapeutic responder versus nonresponder PsA patients.MethodsSerum samples were collected from healthy controls (HC; n = 20) and PsA patients (n = 31), and clinical demographics were obtained. To examine circulatory miRNA in serum from HC and PsA patients, a focused immunology miRNA panel was analyzed utilizing a miRNA Fireplex assay (FirePlex Bioworks Inc.). MiRNA expression was further assessed in responders versus nonresponders according to the European League Against Rheumatism response criteria.ResultsSix miRNA (miR-221-3p, miR-130a-3p, miR-146a-5p, miR-151-5p, miR-26a-5p, and miR-21-5p) were significantly higher in PsA compared to HC (all P < 0.05), with high specificity and sensitivity determined by receiver-operating characteristic curve analysis. Analysis of responder versus nonresponders demonstrated higher baseline levels of miR-221-3p, miR-130a-3p, miR-146a-5p, miR-151-5p, and miR-26a-5p were associated with therapeutic response.ConclusionThis study identified a 6-serum microRNA signature that could be attractive candidates as noninvasive markers for PsA and may help to elucidate the disease pathogenesis.

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