scholarly journals CORRELATION BETWEEN SARS-COV-2 ANTIBODY SCREENING BY IMMUNOASSAY AND NEUTRALIZING ANTIBODY TESTING

2020 ◽  
Author(s):  
ALFREDO MENDRONE-JUNIOR ◽  
CARLA DINARDO ◽  
SUZETE FERREIRA ◽  
ANNA NISHIA ◽  
NANCI SALLES ◽  
...  
Keyword(s):  
Decision Tree ◽  
Neutralizing Antibodies ◽  
Cytopathic Effect ◽  
Neutralization Test ◽  
Antibody Therapy ◽  
Neutralizing Antibody ◽  
Antibody Testing ◽  
Promising Alternative ◽  
Clinical Variables ◽  
Conditional Decision

Background: Passive antibody therapy with convalescent plasma (CP) represents a promising alternative for the treatment of SARS CoV 2 infection. The efficacy of CP therapy has been associated with high titers of neutralizing antibodies (nAbs) in the plasma of recovered patients, but the assays for quantifying nAbs are not widely available. Our goal was to develop a strategy to predict high titers of nAbs based on the results of anti-SARS CoV 2 immunoassays and the clinical characteristics of the CP potential donors. Methods: Two hundred and fourteen CP donors were enrolled and tested for the presence of anti-SARS CoV 2 antibodies using two commercial immunoassays (IA): Anti SARS CoV 2 ELISA IgG EUROIMMUN and Anti SARS CoV 2 Chemiluminescence IgG Abbott. In parallel, quantification of neutralizing antibodies (nAbs) was performed using the Cytopathic effect-based virus neutralization test (CPE VNT). Three criteria for identifying donors with high titers of nAbs (more than 160) were tested: Criterion1: Curve ROC Method; Criterion 2: Conditional decision tree considering only the results from the IA and Criterion 3: Conditional decision tree including both the IA results and the clinical variables. Results: The performance of Abbott and EUROIMMUN immunoassays was similar referring to both S/CO and predictive value for identifying nAbs titers more than 1:160. Regarding the three studied criteria for identifying CP donors with high nAbs titers (more than 1:160): 1) Criterion 1 showed 76.1% accuracy when the S/CO cut-off of 4.65 was used, 2) Criterion 2 presented 76.1% accuracy if the S/CO more than 4.57 was applied and 3) Criterion 3 had 71.6% accuracy if either S/CO more than 4.57 or S/CO between 2.68 and 4.57 and the last COVID-19-related symptoms occurred less than 19 days from donor recruiting were used. Conclusion: The results of SARS-CoV-2 immunoassays (S/CO) can be used to predict high nAbs titers of potential CP donors. This study has proposed three different criteria for identifying donors with more than 160 nAbs titer based on either solely S/CO results or S/CO together with clinical variables, all with high efficacy and accuracy.

scholarly journals Models to inform neutralizing antibody therapy strategies during pandemics: the case of SARS-CoV-2

2021 ◽  
Vol 4 (1) ◽  
pp. 60-71
Author(s):  
Donovan Guttieres ◽  
Anthony J Sinskey ◽  
Stacy L Springs
Keyword(s):  
Value Chain ◽  
Neutralizing Antibodies ◽  
Resource Constraints ◽  
Antibody Therapy ◽  
Neutralizing Antibody ◽  
Epidemiological Data ◽  
Production Costs ◽  
Production Scale ◽  
Design And Optimization ◽  
Critical Components

Abstract Background Neutralizing antibodies (nAbs) against SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) can play an important role in reducing impacts of the COVID-19 pandemic, complementing ongoing public health efforts such as diagnostics and vaccination. Rapidly designing, manufacturing and distributing nAbs requires significant planning across the product value chain and an understanding of the opportunities, challenges and risks throughout. Methods A systems framework comprised of four critical components is presented to aid in developing effective end-to-end nAbs strategies in the context of a pandemic: (1) product design and optimization, (2) epidemiology, (3) demand and (4) supply. Quantitative models are used to estimate product demand using available epidemiological data, simulate biomanufacturing operations from typical bioprocess parameters and calculate antibody production costs to meet clinical needs under various realistic scenarios. Results In a US-based case study during the 9-month period from March 15 to December 15, 2020, the projected number of SARS-CoV-2 infections was 15.73 million. The estimated product volume needed to meet therapeutic demand for the maximum number of clinically eligible patients ranged between 6.3 and 31.5 tons for 0.5 and 2.5 g dose sizes, respectively. The relative production scale and cost needed to meet demand are calculated for different centralized and distributed manufacturing scenarios. Conclusions Meeting demand for anti-SARS-CoV-2 nAbs requires significant manufacturing capacity and planning for appropriate administration in clinical settings. MIT Center for Biomedical Innovation’s data-driven tools presented can help inform time-critical decisions by providing insight into important operational and policy considerations for making nAbs broadly accessible, while considering time and resource constraints.

scholarly journals Effect of a booster-dose of rabies vaccine on the duration of virus neutralizing antibody titers in bovines

1998 ◽  
Vol 31 (4) ◽  
pp. 367-371 ◽  
Author(s):  
Avelino Albas ◽  
Paulo Eduardo Pardo ◽  
Albério Antonio Barros Gomes ◽  
Fernanda Bernardi ◽  
Fumio Honma Ito
Keyword(s):  
Immune Response ◽  
Neutralizing Antibodies ◽  
Booster Dose ◽  
Neutralization Test ◽  
Neutralizing Antibody ◽  
Rabies Vaccine ◽  
Western Region ◽  
Humoral Immune ◽  
Paulo State ◽  
Antibody Titers

Humoral immune response using inactivated rabies vaccine was studied in 35 nelore cross-bred bovines of western region of São Paulo state. Ninety days after vaccination, 13 (92.8%) animals presented titers 30.5IU/ml, through mouse neutralization test. After 180 days, 9 (64.3%) sera showed titers 30.5IU/ml, after 270 days, only one (7.1%) showed a titer of 0.51IU/ml, and after 360 days, all animals showed titers < 0.5IU/ml. Group of animals receiving booster dose 30 days after vaccination presented, two months after, all with titers > 0.5IU/ml. At 180 days, 17 (80.9%) sera presented titers > 0.5IU/ml; at 270 days, 15 (71.4%), with titers 30.5IU/ml and at 360 days, 4 (19.0%), with titers 30.5IU/ml. Booster-dose ensured high levels of neutralizing antibodies for at least three months, and 240 days after revaccination, 71.4% of animals were found with titers 30.5IU/ml.

scholarly journals Performance Evaluation of the BZ COVID-19 Neutralizing Antibody Test for the Culture-Free and Rapid Detection of SARS-CoV-2 Neutralizing Antibodies

Diagnostics ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2193
Author(s):  
Bo Kyeung Jung ◽  
Jung Yoon ◽  
Joon-Yong Bae ◽  
Jeonghun Kim ◽  
Man-Seong Park ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Diagnostic Performance ◽  
Neutralization Test ◽  
Neutralizing Antibody ◽  
Antibody Test ◽  
Lower Sensitivity ◽  
Control Line ◽  
Perfect Agreement ◽  
Strong Negative Correlation ◽  
Percent Inhibition

Rapid and accurate measurement of SARS-CoV-2 neutralizing antibodies (nAbs) can aid in understanding the development of immunity against COVID-19. This study evaluated the diagnostic performance of a rapid SARS-CoV-2 nAb detection test called the BZ COVID-19 nAb test BZ-nAb (BZ-nAb; BioZentech). Using the 90% plaque-reduction neutralization test (PRNT-90) as a reference, 104 serum specimens collected from COVID-19-positive and -negative patients were grouped into 40 PRNT-90-positive and 64 PRNT-90-negative specimens. The performance of the BZ-nAb was compared with that of the cPass surrogate virus neutralization test (cPass sVNT; Genscript). The BZ-nAb showed a sensitivity ranging from 92.5%–95.0% and specificity ranging from 96.9%–100%, whereas cPass sVNT showed a sensitivity of 100% (95% confidence interval (CI) 90.5%–100%) and specificity of 98.4% (95% CI, 91.6%–100%). The dilution factor obtained with PRNT-90 showed a stronger correlation with the percent inhibition of cPass sVNT (r = 0.8660, p < 0.001) compared with the test and control line ratio (T/C ratio) of the BZ-nAb (r = −0.7089, p < 0.001). An almost perfect agreement was seen between the BZ-nAb and cPass sVNT results, with a strong negative correlation between the BZ-nAb T/C ratio and cPass sVNT percent inhibition (r = −0.8022, p < 0.001). In conclusion, the diagnostic performance of the BZ-nAb was comparable to that of the cPass sVNT, although the BZ-nAb had a slightly lower sensitivity.

scholarly journals Evaluation of high-throughput SARS-CoV-2 serological assays in a longitudinal cohort of mild COVID-19 patients: sensitivity, specificity and association with virus neutralization test

2020 ◽  
Author(s):  
Antonin Bal ◽  
Bruno Pozzetto ◽  
Mary-Anne Trabaud ◽  
Vanessa Escuret ◽  
Muriel Rabilloud ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Healthcare Workers ◽  
Neutralization Test ◽  
Neutralizing Antibody ◽  
Virus Neutralization Test ◽  
Virus Neutralization ◽  
Serological Tests ◽  
Course Of Disease ◽  
Antibody Titers ◽  
Sensitivity Specificity

BackgroundThe association between SARS-CoV-2 commercial serological assays and virus neutralization test (VNT) has been poorly explored in mild COVID-19 patients.MethodsA total of 439 serum specimens were longitudinally collected from 76 healthcare workers with RT-PCR-confirmed COVID-19. The sensitivity (determined weekly) of nine commercial serological assays were evaluated. Specificity was assessed using 69 pre-pandemic sera. Correlation, agreement and concordance with the VNT were also assessed on a subset of 170 samples. Area under the ROC curve (AUC) was estimated at several neutralizing antibody titers.ResultsThe Wantai Total Ab assay targeting the receptor binding domain (RBD) within the S protein presented the best sensitivity at different times during the course of disease. The specificity was greater than 95% for all tests except for the Euroimmun IgA assay. The overall agreement with the presence of neutralizing antibodies ranged from 62.2% (95%CI; 56.0-68.1) for bioMérieux IgM to 91.2% (87.0-94.2) for Siemens. The lowest negative percent agreement (NPA) was found with the Wantai Total Ab assay (NPA 33% (21.1-48.3)). The NPA for other total Ab or IgG assays targeting the S or the RBD was 80.7% (66.7-89.7), 90.3 (78.1-96.1) and 96.8% (86.8-99.3) for Siemens, bioMérieux IgG and DiaSorin, respectively. None of commercial assays have sufficient performance to detect a neutralizing titer of 80 (AUC<0.76).ConclusionsAlthough some assays presented a better agreement with VNT than others, the present findings emphasize that commercialized serological tests including those targeting the RBD cannot substitute a VNT for the assessment of functional antibody response.

scholarly journals The Trend of Neutralizing Antibody Response Against SARS-CoV-2 and the Cytokine/Chemokine Release in Patients with Differing Severities of COVID-19: All Individuals Infected with SARS-CoV-2 Obtained Neutralizing Antibody

2020 ◽  
Author(s):  
Lidya Handayani Tjan ◽  
Tatsuya Nagano ◽  
Koichi Furukawa ◽  
Mitsuhiro Nishimura ◽  
Jun Arii ◽  
...  
Keyword(s):  
Antibody Production ◽  
Neutralizing Antibodies ◽  
Clinical Course ◽  
Antibody Therapy ◽  
Neutralizing Antibody ◽  
Older Individuals ◽  
First Line ◽  
Critical Patients ◽  
High Level ◽  
Different Levels

Background: COVID-19 patients show a wide clinical spectrum ranging from mild respiratory symptoms to severe and fatal disease, and older individuals are known to be affected more severely. Neutralizing antibody for viruses is critical for their elimination, and increased cytokine/chemokine levels are thought to be related to COVID-19 severity. However, the trend of the neutralizing antibody production and cytokine/chemokine levels during the clinical course of COVID-19 patients with differing levels of severity has not been established. Methods: We serially collected 45 blood samples from 12 patients with different levels of COVID-19 severity, and investigated the trend of neutralizing antibody production using authentic SARS-CoV-2 and cytokine/chemokine release in the patients' clinical courses. Results: All 12 individuals infected with SARS-CoV-2 had the neutralizing antibody against it, and the antibodies were induced at approx. 4-10 days after the patients' onsets. The antibodies in the critical and severe cases showed high neutralizing activity in all clinical courses. Most cytokine/chemokine levels were clearly high in the critical patients compared to those with milder symptoms. Conclusion: Neutralizing antibodies against SARS-CoV-2 were induced at a high level in the severe COVID-19 patients, indicating that abundant virus replication occurred. Cytokines/chemokines were expressed more in the critical patients, indicating that high productions of cytokines/chemokines have roles in the disease severity. These results may indicate that plasma or neutralizing antibody therapy could be a first-line treatment for older patients to eliminate the virus, and corticosteroid therapy could be effective to suppress the cytokine storm after the viral genome's disappearance.

scholarly journals IMMUNOLOGICAL REACTIONS OF THE COXSACKIE VIRUSES

1950 ◽  
Vol 92 (5) ◽  
pp. 463-482 ◽  
Author(s):  
Joseph L. Melnick ◽  
Nada Ledinko
Keyword(s):  
North Carolina ◽  
Neutralizing Antibodies ◽  
Neutralization Test ◽  
Normal Population ◽  
Standard Procedure ◽  
Neutralizing Antibody ◽  
The United States ◽  
Immune Serum ◽  
Newborn Mice ◽  
Immunological Reactions

The neutralization test is a reliable and useful procedure for following immunological reactions of the Coxsackie viruses (C virus). The standard procedure has been an incubation period of 1 hour at room temperature followed by subcutaneous inoculation into newborn mice. However, this time and temperature are not critical, for the virus in neutralized within 10 minutes of mixing with immune serum and remains neutralized for long periods. During the variable incubation periods used, the control virus remained active, even in dilute suspensions. The neutralization test is not affected by the presence or absence of complement. Neutralizing antibody is stable at 65°C. for 30 minutes, and immune serum has to be heated to 80°C. for 30 minutes before the antibody is no longer detectable. As the quantity of virus is increased, the quantity of serum required for neutralization likewise increases, but not in a regular or predictable fashion. Neutralized mixtures of the virus can be made infective again by simple dilution before inoculation. The neutralization test is a satisfactory means for typing Coxsackie viruses. At least seven antigenic types have been identified. Similar antigenic types have been found to be scattered over wide areas. Thus the Conn.-5 type was present in 1948 in Massachusetts, Connecticut, New York, and North Carolina. The Texas-1 type was present in 1943 in Connecticut and in 1948 in North Carolina and Texas. Further information on the specificity of the neutralizing antibody response has been obtained from a study of the occurrence and development of antibodies in 6 patients who contracted infections with one or another of the C viruses while working with them in the laboratory. From each patient a virus was isolated during the illness. No patient had detectable antibodies to his strain before his illness, but each soon thereafter developed antibodies to his own strain and to the prototype strain to which it was related. By means of the neutralization test, it has been shown that a family epidemic may include two different immunological types of virus. Neutralizing antibodies appear at the time of or soon after onset of illness, increase rapidly to titers of about 1:1000 which are maintained during the period of 1 to 3 months following infection, and are still present 2 years later, although at lower levels. Neutralizing antibodies are present in the normal population. In North Carolina, over 80 per cent of the children have antibodies at birth. The level falls rapidly to a minimum of 14 per cent at the age of 1, and then it quickly rises to reach the adult level at the age of 7. Gamma globulin collected in various parts of the United States between 1944 and 1949 and in Denmark in 1949 neutralizes at least four antigenically different Coxsackie viruses.

SARS-CoV-2 Neutralizing Antibodies for COVID-19 Prevention and Treatment

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
Dapeng Li ◽  
Gregory D. Sempowski ◽  
Kevin O. Saunders ◽  
Priyamvada Acharya ◽  
Barton F. Haynes
Keyword(s):  
Neutralizing Antibodies ◽  
Antibody Therapy ◽  
Neutralizing Antibody ◽  
Annual Review ◽  
Publication Date ◽  
The Past ◽  
Therapeutic Drugs ◽  
Therapeutic Uses ◽  
The Us ◽  
Prevention And Treatment

Prophylactic and therapeutic drugs are urgently needed to combat coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Over the past year, SARS-CoV-2 neutralizing antibodies have been developed for preventive or therapeutic uses. While neutralizing antibodies target the spike protein, their neutralization potency and breadth vary according to recognition epitopes. Several potent SARS-CoV-2 antibodies have shown degrees of success in preclinical or clinical trials, and the US Food and Drug Administration has issued emergency use authorization for two neutralizing antibody cocktails. Nevertheless, antibody therapy for SARS-CoV-2 still faces potential challenges, including emerging viral variants of concern that have antibody-escape mutations and the potential for antibody-mediated enhancement of infection or inflammation. This review summarizes representative SARS-CoV-2 neutralizing antibodies that have been reported and discusses prospects and challenges for the development of the next generation of COVID-19 preventive or therapeutic antibodies. Expected final online publication date for the Annual Review of Medicine, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

scholarly journals Corona Virus Disease-19 serology, inflammatory markers, hospitalizations, case finding, and aging

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252818
Author(s):  
Ernst J. Schaefer ◽  
Latha Dulipsingh ◽  
Florence Comite ◽  
Jessica Jimison ◽  
Martin M. Grajower ◽  
...  
Keyword(s):  
Inflammatory Markers ◽  
Neutralizing Antibodies ◽  
Virus Disease ◽  
Neutralizing Antibody ◽  
Case Finding ◽  
Immunoglobulin M ◽  
Antibody Testing ◽  
Wide Range ◽  
Older Subjects ◽  
Antibody Levels

Most deaths from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection occur in older subjects. We assessed the utility of serum inflammatory markers interleukin-6 (IL-6), C reactive protein (CRP), and ferritin (Roche, Indianapolis, IN), and SARS-CoV-2 immunoglobulin G (IgG), immunoglobulin M (IgM), and neutralizing antibodies (Diazyme, Poway, CA). In controls, non-hospitalized subjects, and hospitalized subjects assessed for SARS-CoV-2 RNA (n = 278), median IgG levels in arbitrary units (AU)/mL were 0.05 in negative subjects, 14.83 in positive outpatients, and 30.61 in positive hospitalized patients (P<0.0001). Neutralizing antibody levels correlated significantly with IgG (r = 0.875; P<0.0001). Having combined values of IL-6 ≥10 pg/mL and CRP ≥10 mg/L occurred in 97.7% of inpatients versus 1.8% of outpatients (odds ratio 3,861, C statistic 0.976, P = 1.00 x 10−12). Antibody or ferritin levels did not add significantly to predicting hospitalization. Antibody testing in family members and contacts of SARS-CoV-2 RNA positive cases (n = 759) was invaluable for case finding. Persistent IgM levels were associated with chronic COVID-19 symptoms. In 81,624 screened subjects, IgG levels were positive (≥1.0 AU/mL) in 5.21%, while IgM levels were positive in 2.96% of subjects. In positive subjects median IgG levels in AU/mL were 3.14 if <30 years of age, 4.38 if 30–44 years of age, 7.89 if 45–54 years of age, 9.52 if 55–64 years of age, and 10.64 if ≥65 years of age (P = 2.96 x 10−38). Our data indicate that: 1) combined IL-6 ≥10 pg/mL and CRP ≥10 mg/L identify SARS-CoV-2 positive subjects requiring hospitalization; 2) IgG levels were significantly correlated with neutralizing antibody levels with a wide range of responses; 3) IgG levels have significant utility for case finding in exposed subjects; 4) persistently elevated IgM levels are associated with chronic symptoms; and 5) IgG levels are significantly higher in positive older subjects than their younger counterparts.

scholarly journals Evaluation of Commercial Anti-SARS-CoV-2 Neutralizing Antibody Assays in seropositive subjects

2022 ◽  
Author(s):  
Kahina Saker ◽  
Bruno Pozzetto ◽  
Vanessa ESCURET ◽  
Virginie Pitiot ◽  
Amélie Massardier-Pilonchéry ◽  
...  
Keyword(s):  
Functional Ability ◽  
Neutralizing Antibodies ◽  
Neutralization Test ◽  
Neutralizing Antibody ◽  
Added Value ◽  
P Value ◽  
Antibody Assays ◽  
Qualitative Test ◽  
User Friendly ◽  
Commercial User

The virus neutralization test (VNT) is the reference for the assessment of the functional ability of neutralizing antibodies (NAb) to block SARS-CoV-2 entry into cells. New competitive immunoassays measuring antibodies preventing interaction between the spike protein and its cellular receptor are proposed as surrogate VNT (sVNT). We tested three commercial sVNT (a qualitative immunochromatographic test and two quantitative immunoassays named YHLO and TECO) together with a conventional anti-spike IgG assay (bioMerieux) in comparison with an in-house plaque reduction neutralization test (PRNT50) using the original 19A strain and different variants of concern (VOC), on a panel of 306 sera from naturally-infected or vaccinated patients. The qualitative test was rapidly discarded because of poor sensitivity and specificity. Areas under the curve of YHLO and TECO assays were, respectively, 85.83 and 84.07 (p-value >0.05) using a positivity threshold of 20 for PRNT50, and 95.63 and 90.35 (p-value =0.02) using a threshold of 80. However, the performances of YHLO and bioMerieux were very close for both thresholds, demonstrating the absence of added value of sVNT compared to a conventional assay for the evaluation of the presence of NAb in seropositive subjects. In addition, the PRNT50 assay showed a reduction of NAb titers towards different VOC in comparison to the 19A strain that could not be appreciated by the commercial tests. Despite the good correlation between the anti-spike antibody titer and the titer of NAb by PRNT50, our results highlight the difficulty to distinguish true NAb among the anti-RBD antibodies with commercial user-friendly immunoassays.

scholarly journals Predicting COVID-19 Vaccine Efficacy from Neutralizing Antibody Levels

2021 ◽  
Author(s):  
Majid R. Abedi ◽  
Samuel Dixon ◽  
Timothy Guyon ◽  
Serene Hsu ◽  
Aviva R. Jacobs ◽  
...  
Keyword(s):  
High Throughput ◽  
Vaccine Efficacy ◽  
Neutralizing Antibodies ◽  
Neutralization Test ◽  
Neutralizing Antibody ◽  
Published Data ◽  
Real World Data ◽  
Symptomatic Infection ◽  
Viral Neutralization ◽  
Antibody Levels

Recent studies using data accrued from global SARS-CoV-2 vaccination efforts have demonstrated that breakthrough infections are correlated with levels of neutralizing antibodies. The decrease in neutralizing antibody titers of vaccinated individuals over time, combined with the emergence of more infectious variants of concern has resulted in waning vaccine efficacy against infection and a rise in breakthrough infections. Here we use a combination of neutralizing antibody measurements determined by a high throughput surrogate viral neutralization test (sVNT) together with published data from vaccine clinical trials and comparative plaque reduction neutralization test (PRNT) between SARS-CoV-2 variants to develop a model for vaccine efficacy (VE) against symptomatic infection. Vaccine efficacy estimates using this model show good concordance with real world data from the US and Israel. Our work demonstrates that appropriately calibrated neutralizing antibody measurements determined by high throughput sVNT can be used to provide a semi-quantitative estimate of protection against infection. Given the highly variable antibody levels among the vaccinated population, this model may be of use in identification of individuals with an elevated risk of breakthrough infections.

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