Borderline and weakly positive antibody levels against the S-protein of SARS-CoV-2 exhibit limited agreement with virus neutralization titres

Quantitative SARS-CoV-2 antibody assays against the spike (S) protein are useful for monitoring immune response after infection or vaccination. We compared the results of three chemiluminescent immunoassays (CLIAs) (Abbott, Roche, Siemens) and a surrogate virus neutralization test (sVNT, GenScript) using 191 sequential samples from 32 COVID-19 patients. All assays detected >90% of samples collected 14 days after symptom onset (Abbott 97.4%, Roche 96.2%, Siemens 92.3%, and GenScript 96.2%), and overall agreement among the four assays was 91.1% to 96.3%. When we assessed time-course antibody levels, the Abbott and Siemens assays showed higher levels in patients with severe disease (p < 0.05). Antibody levels from the three CLIAs were correlated (r = 0.763–0.885). However, Passing–Bablok regression analysis showed significant proportional differences between assays and converting results to binding antibody units (BAU)/mL still showed substantial bias. CLIAs had good performance in predicting sVNT positivity (Area Under the Curve (AUC), 0.959–0.987), with Abbott having the highest AUC value (p < 0.05). SARS-CoV-2 S protein antibody levels as assessed by the CLIAs were not interchangeable, but showed reliable performance for predicting sVNT results. Further standardization and harmonization of immunoassays might be helpful in monitoring immune status after COVID-19 infection or vaccination.

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A Standardized Enzyme-Linked Immunosorbent Assay for Infectious Bronchitis Virus: Comparison with Hemagglutination-Inhibition and Virus-Neutralization Assays for Measuring Protective Antibody Levels in Chickens

Avian Diseases ◽

10.2307/1590911 ◽

1988 ◽

Vol 32 (3) ◽

pp. 451 ◽

Cited By ~ 4

Author(s):

Charles Perrotta ◽

Cheryl Furtek ◽

Richard A. Wilson ◽

Barrett S. Cowen ◽

Robert J. Eckroade

Keyword(s):

Immunosorbent Assay ◽

Infectious Bronchitis Virus ◽

Hemagglutination Inhibition ◽

Virus Neutralization ◽

Enzyme Linked Immunosorbent Assay ◽

Protective Antibody ◽

Infectious Bronchitis ◽

Antibody Levels

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Dynamic Alterations of Anti-S-Protein Igg Subclasses and of Th1/Th2 Responses are Hallmarks of Acute Severe COVID-19 Disease

10.21203/rs.3.rs-432867/v1 ◽

2021 ◽

Author(s):

Yun Shan Goh ◽

Siew-Wai Fong ◽

Siti Naqiah Amrun ◽

Cheryl Lee ◽

Pei Xiang Hor ◽

...

Keyword(s):

Disease Severity ◽

Severe Disease ◽

Th2 Response ◽

S Protein ◽

Th1 Response ◽

Humoral Immune ◽

Mild Disease ◽

Humoral Immune Responses ◽

Disease Spectrum ◽

Antibody Levels

Abstract PurposeCOVID-19, caused by Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2), has a wide disease spectrum ranging from asymptomatic to severe. While it is widely accepted that specific humoral immune responses are critical in controlling the infection, the relationship between the humoral immune response and disease severity is currently unclear.MethodsUsing a flow cytometry-based assay to detect specific antibodies against full length S protein, we compared the antibody levels between patients from different severity groups. We also analysed the cytokine profiles of patients from different severity groups by multiplex microbead-based immunoassay.ResultsWe found an association between specific IgM, IgA and IgG against the spike protein and disease severity. By comparing the ratio of Th1 IgG1 and IgG3 to Th2 IgG2 and IgG4, we observed that all severity groups exhibited a ratio that was skewed towards a stronger Th1 response over Th2 response. In addition to the strong Th1 response, patients with severe disease also developed a Th2 response, as exemplified by the smaller ratio of IgG1 and IgG3 over IgG2 and IgG4 and the smaller Th1/Th2 cytokine ratios, compared to patients with mild disease severity. ConclusionThe results suggest that acute severity or disease resolution is associated with a specific immunological phenotype. A smaller skew towards a Th1 response over Th2 response, during infection, may contribute to disease progression, while a greater skew towards a Th1 response over Th2 response may contribute to a better disease outcome. This may suggest potential therapeutic approaches to COVID-19 disease management.

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Humoral Immunity and Adverse Events after Vaccination Against COVID-19 By a Vector Based Vaccine Sputnik V in Patients with Chronic Myeloid Leukemia

Blood ◽

10.1182/blood-2021-152701 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 4599-4599

Author(s):

Ekaterina Yu. Chelysheva ◽

Anna Petrova ◽

Oleg A. Shukhov ◽

Margarita Gurianova ◽

Anastasiya Bykova ◽

...

Keyword(s):

Chronic Myeloid Leukemia ◽

Adverse Events ◽

Myeloid Leukemia ◽

Reverse Correlation ◽

Molecular Response ◽

Elderly Persons ◽

S Protein ◽

Specific Antibodies ◽

Test Systems ◽

Antibody Levels

Abstract Introduction Data on the effectiveness and safety of new vaccines against COVID-19 in patients (pts) with hematological diseases are just beginning to accumulate. We planned to obtain such information for pts with chronic myeloid leukemia (CML) during vaccination. Objective. To evaluate the antibodies formation and adverse events (AEs) after vaccination against COVID-19 in pts with CML Materials and methods. All pts with CML diagnosis who applied to the National Research Center for Hematology (NRCH, Moscow, Russia) for outpatient or remote consultations were suggested to prospectively report the AEs after getting a vaccination against COVID-19 by the most frequently used vector-based vaccine GamCovidVac (Sputnik V). Two vaccine components with the interval of 21 days were given at the vaccination facilities, as prescribed. At least after 3 weeks after the 2 nd injection, pts were advised to perform a blood test for the specific antibodies against spike (S) protein of SARS-CoV-2. A semi-quantitative test detecting the SARS-CoV-2 S1 subunit (RBD) IgG antibodies by enzyme-linked immunoassay (ELISA) kit was used in the clinic. The results were considered positive with the cutoff index >1,1. The use of any other lab tests detecting antibodies to S protein of SARS-CoV-2 was acceptable as well. Results. In total, 66 pts with chronic phase of CML received a vaccination by Sputnik V in the 7 months period (from 18.12.2020 to 20.07.2021). Me age was 54 years (range 29 - 89 years), 34 (52%) were males. Median (Me) CML duration was 8 years (from the moment of diagnostics up to 20 years). Fifty one (77%) pt received TKI therapy and 15 (23%) were off-therapy at the time of vaccination, including 12 (18%) in a treatment-free remission and 3 (4,5%) pts in the process of diagnosis. Deep and major molecular response (MMR) was in 46 (70%) and 7 (11%) pts, respectively. Two (3%) pts had a molecular response MR2, 11 (17%) had no MR2. Eight (12%) pts had a history of COVID-19 manifestation prior to vaccination. Me time for testing for the antibodies was 27 days (range 5-77) after the 2 nd vaccine injection. The tests were done in 44 (67%) of pts and revealed positive by any of the test systems in 42 (95%) pts. ELISA test was used in 30 (45%) pts and was positive in 25 (83%) of 30 pts. Me cutoff index in the positive samples was 7,7 (range 1,1 - 12) and corresponded to the value observed in healthy people after vaccination (medical stuff, data not shown). In all 3 pts with the history COVID 19, the index of positivity was above the Me value (Fig. 1, 2). Other test systems were used in 14 (21%) pts, in all 14 (100%) the antibodies were found. In 3 of 5 patients with the cutoff index<1 the antibodies were detected by using other test systems, but all with a level slightly above the detection threshold. Me age of these 5 pts was 63 years (range 59- 70), Me time of analysis was 49 days (range 23-59) after 2 nd vaccine shot. All these pts were on treatment by tyrosine kinase inhibitors, 3 pts with MMR and deeper, 1 pt with MR2 and 1 pt without MR2. A weak reverse correlation of the antibody levels with the time after vaccination was noted ( r = - 0,39, p = 0,033). A very weak reverse correlation with age was observed ( r = - 0,28, p = 0,127) (Fig. 1, 2). No AEs after the vaccination were observed in 25 (38%) pts while 41 (62%) pts reported the AEs and 7 (10%) pts did not report their reactions. The AEs were as follows: local pain/discomfort in the injection site in 19 (29%) pts, weakness and/or drowsiness in 20 (30%), fever and/or chills in 16 (24%), other reactions in 8 (12%) including headache, heartbeat, lower back pain, pain in limbs, activation of herpes infection. Conclusion: The single center study revealed no unusual or unexpected AEs in CML pts after the vaccination against COVID-19 by Sputnik V vaccine. The proportion of CML pts with specific antibodies after was 95% which is close to the published results of the 3rd phase study. No significant correlation was found with age (r = -0,28, p = 0,127), however, the absence or very low antibody levels were detected in individual patients aged about 60-70 years. This data raise a question of a necessity for a non-specific protection (masks, respirators, distance etc) and probably considering additional vaccination in some elderly persons. The duration of a humoral response against COVID-19, protective antibody titer and connection with clinical outcomes in CML pts need further evaluation in parallel with a common population. Figure 1 Figure 1. Disclosures Chelysheva: Pfizer: Speakers Bureau; Pharmstandart: Speakers Bureau; Bristol Myers Squibb: Speakers Bureau; Novartis Pharma: Speakers Bureau. Petrova: Pfizer: Speakers Bureau; Novartis Pharma: Speakers Bureau. Gurianova: Pfizer: Speakers Bureau. Turkina: Pharmstandart: Speakers Bureau; Pfizer: Speakers Bureau; Novartis Pharma: Speakers Bureau; Bristol Myers Squibb: Speakers Bureau.

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Waning antibody levels after vaccination with mRNA BNT162b2 and inactivated CoronaVac COVID-19 vaccines in Hong Kong blood donors

10.1101/2021.12.05.21267330 ◽

2021 ◽

Author(s):

Shirley LL Kwok ◽

Samuel MS Cheng ◽

Jennifer NS Leung ◽

Kathy Leung ◽

Cheuk-Kwong Lee ◽

...

Keyword(s):

Hong Kong ◽

Vaccination Programme ◽

Blood Donors ◽

Neutralization Test ◽

Virus Neutralization Test ◽

Virus Neutralization ◽

Inactivated Vaccine ◽

Immunosorbent Assays ◽

Antibody Levels

AbstractBoth inactivated vaccine (CoronaVac; Sinovac) and mRNA vaccine (Comirnaty/BNT162b2; Fosun-Pharma/BioNTech) are available in Hong Kong’s COVID-19 Vaccination Programme. We reported waning antibody levels by enzyme-linked immunosorbent assays (ELISA) and surrogate virus neutralization test (sVNT) among 850 fully vaccinated blood donors (i.e., received two doses). The BNT162b2 group’s antibody levels remain over the 50% protection threshold within six months, and the CoronaVac’s group’s median antibody levels begin to fall below the 50% protection threshold two months after vaccination.

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Inference of SARS-CoV-2 spike-binding neutralizing antibody titers in sera from hospitalized COVID-19 patients by using commercial enzyme and chemiluminescent immunoassays

10.1101/2020.09.07.20188151 ◽

2020 ◽

Author(s):

Arantxa Valdivia ◽

Ignacio Torres ◽

Victor Latorre ◽

Carla Frances-Gomez ◽

Eliseo Albert ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Neutralizing Antibody ◽

Neutralization Assay ◽

Virus Neutralization ◽

Pseudotyped Virus ◽

S Protein ◽

Neutralizing Activity ◽

Virus Neutralization Assay ◽

Degree Correlation ◽

Antibody Titers

Background: Whether antibody levels measured by commercially-available enzyme or chemiluminescent immunoassays targeting the SARS-CoV-2 spike (S) protein can act as a proxy for serum neutralizing activity remains to be established for many of these assays. Objectives: To evaluate the degree of correlation between neutralizing antibodies (NtAb) binding the SARS-CoV-2 Spike (S) protein and SARS-CoV-2-S-IgG levels measured by four commercial immunoassays in sera drawn from hospitalized COVID-19 patients. Patients and Methods: Ninety sera from 51 hospitalized COVID-19 patients were assayed by a pseudotyped virus neutralization assay, the LIAISON SARS-CoV-2 S1/S2 IgG, the Euroimmun SARS-CoV-2 IgG ELISA, the MAGLUMI 2019-nCoV IgG and the COVID-19 ELISA IgG assays. Results: Overall, the results obtained with the COVID-19 ELISA IgG test showed the highest agreement with the NtAb assay (κ, 0.85; 95% CI, 0.63-1). The most sensitive tests were the pseudotyped virus NtAb assay and the COVID-19 ELISA IgG assay (92.2% for both). Overall, the degree correlation between antibody titers resulting in 50% virus neutralization (NtAb50) in the pseudotyped virus assay and SARS-CoV-2 IgG levels was strong for the Euroimmun SARS-CoV-2 IgG ELISA (Rho=0.73) and moderate for the remaining assays (Rho=0.48 to 0.59). The kinetic profile of serum NtAb50 titers could not be reliably predicted by any of the SARS-CoV-2 IgG immunoassays. Conclusions: the suitability of SARS-CoV-2-S-IgG commercial immunoassays for inferring neutralizing activity of sera from hospitalized COVID-19 patients varies widely across tests and is influenced by the time of sera collection after the onset of symptoms.

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Neutralizing antibody response in non-hospitalized SARS-CoV-2 patients

10.1101/2020.08.07.20169961 ◽

2020 ◽

Author(s):

Natalia Ruetalo ◽

Ramona Businger ◽

Karina Althaus ◽

Simon Fink ◽

Felix Ruoff ◽

...

Keyword(s):

Antibody Response ◽

Western Blot ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Virus Neutralization ◽

Surrogate Markers ◽

High Antibody ◽

Serological Survey ◽

Course Of Disease ◽

Antibody Levels

The majority of infections with SARS-CoV-2 are asymptomatic or mild without the necessity of hospitalization. It is of importance to reveal if these patients develop an antibody response against SARS-CoV-2 and to define which antibodies confer virus neutralization. We conducted a comprehensive serological survey of 49 patients with a mild course of disease and quantified neutralizing antibody responses against a clinical SARS-CoV-2 isolate employing human cells as targets. Four patients (8%), even though symptomatic, did not develop antibodies against SARS-CoV-2 and two other patients (4%) were only positive in one of the six serological assays employed. For the remainder, antibody response against the S-protein correlated with serum neutralization whereas antibodies against the nucleocapsid were poor predictors of virus neutralization. Regarding neutralization, only six patients (12%) could be classified as highly neutralizers. Furthermore, sera from several individuals with fairly high antibody levels had only poor neutralizing activity. In addition, employing a novel serological Western blot system to characterize antibody responses against seasonal coronaviruses, we found that antibodies against the seasonal coronavirus 229E might contribute to SARS-CoV-2 neutralization. Altogether, we show that there is a wide breadth of antibody responses against SARS-CoV-2 in patients that differentially correlate with virus neutralization. This highlights the difficulty to define reliable surrogate markers for immunity against SARS-CoV-2.

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Choosing the right tool for the job: A comprehensive assessment of serological assays for SARS-CoV-2 as surrogates for authentic virus neutralization

10.1101/2021.04.14.21255399 ◽

2021 ◽

Author(s):

Nicholas Wohlgemuth ◽

Kendall Whitt ◽

Sean Cherry ◽

Ericka Kirkpatrick Roubidoux ◽

Chun-Yang Lin ◽

...

Keyword(s):

Neutralizing Antibody ◽

Virus Neutralization ◽

Diagnostic Tools ◽

Pseudotyped Virus ◽

Global Pandemic ◽

Level 3 ◽

The Right ◽

Antibody Levels ◽

Reliable Methods ◽

Biosafety Level

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in late 2019 and has since caused a global pandemic resulting in millions of cases and deaths. Diagnostic tools and serological assays are critical for controlling the outbreak, especially assays designed to quantitate neutralizing antibody levels, considered the best correlate of protection. As vaccines become increasingly available, it is important to identify reliable methods for measuring neutralizing antibody responses that correlate with authentic virus neutralization but can be performed outside of biosafety level 3 (BSL3) laboratories. While many neutralizing assays using pseudotyped virus have been developed, there have been few studies comparing the different assays to each other as surrogates for authentic virus neutralization. Here we characterized three enzyme-linked immunosorbent assays (ELISAs) and three pseudotyped VSV virus neutralization assays and assessed their concordance with authentic virus neutralization. The most accurate assays for predicting authentic virus neutralization were luciferase and secreted embryonic alkaline phosphatase (SEAP) expressing pseudotyped virus neutralizations, followed by GFP expressing pseudotyped virus neutralization, and then the ELISAs.

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Periodic Evaluation of Anti-SARS-CoV-2 Antibody Levels and Determination of Surrogate Virus Neutralization in Healthcare Workers with COVID-19

Mikrobiyoloji Bulteni ◽

10.5578/mb.20219704 ◽

2021 ◽

Vol 55 (4) ◽

pp. 507-518

Author(s):

Yeşim Tuyji Tok ◽

Mert Ahmet Kuşkucu ◽

Devrim Sarıbal ◽

Seda Salman Yılmaz ◽

Okan Kadir Nohut ◽

...

Keyword(s):

Healthcare Workers ◽

Virus Neutralization ◽

Periodic Evaluation ◽

Antibody Levels

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Serological testing for COVID-19

Journal of Lung Pulmonary & Respiratory Research ◽

10.15406/jlprr.2021.08.00248 ◽

2021 ◽

Vol 8 (2) ◽

pp. 35-39

Author(s):

Attapon Cheepsattayakorn ◽

Ruangrong Cheepsattayakorn

Keyword(s):

Polymerase Chain Reaction ◽

Reverse Transcriptase ◽

Neutralizing Antibody ◽

Bibliographic Databases ◽

Chain Reaction ◽

Igg Antibody ◽

S Protein ◽

Specimen Collection ◽

Polymerase Chain ◽

Antibody Levels

The objectives of this study are to identify the rapid, appropriate, screening, definite and novel methods of diagnosis of SARS-CoV-2 (COVID-19) infection, including SARS-CoV-2 (COVID-19) variants among various degree of COVID-19 severity for rapid prevention and control of SARS-CoV-2 (COVID-19) transmission. Methods of The Study: A comprehensive search was carried out in mainstream bibliographic databases or Medical Subject Headings, including ScienDirect, PubMed, Scopus, and ISI Web of Science. The search was applied to the articles that were published between 1971 and early March 2021. Results: With strict literature search and screening processes, it yielded 40 articles from 78 articles of initial literature database. Characteristically, after infection, antibodies are detected in the blood of individuals, particularly individuals with few or mild symptoms. In patients with varying symptoms of COVID-19 and negative results of reverse-transcriptase-polymerase-chain reaction (RT-PCR) tests, the testing has a significantly clinical role when nasopharyngeal swabs are taken more than 5 days after symptom onset. The Royal College of Pathologists (RCPath) developed seven principles for production of a COVID-19 testing strategy. Testing being carried out for a purpose is one of these RCPath’s principles. Nevertheless, denial of requesting SARS-CoV-2 (COVID-19) antibody tests for reassurance should be cautioned. With a lower antibody levels, whether the protective immunity will be sustained is questionable. Several immune-based assays were developed against different SARS-CoV-2 (COVID-19) viral proteins as the followings: 1) Entire Spike (S) protein, IgG antibody from patient serum can cross-react with SARS-CoV and MERS-CoV, 2) S1 subunit of Spike (S) protein, IgA, IgG antibodies from patient serum can cross-react with SARS-CoV only, 3) Receptor-binding domain (RBD), IgG antibody from patient serum can cross-react with SARS-CoV only, and 4) Nucleocapsid (N), IgG antibody from patient serum can cross-react with SARS-CoV only. Long et al demonstrated in their study that IgG antibody and neutralizing antibody levels initiate decreasing within 2-3 months after infection in the majority of persons with recovery from SARS-CoV-2 (COVID-19) infection. An analytical study of the dynamics of neutralizing antibody titers demonstrated reduced neutralizing antibodies around 6-7 weeks after illness onset. In conclusion, the nucleic acid amplification tests may be poorly timed specimen collection, poor-quality specimen collection, long wait times for generating the results, and requirement of trained laboratory technicians. Serological data greatly supplement the laboratory results from the quantitative reverse-transcriptase-polymerase-chain reaction (qRT-PCR), the design of virus elimination programs (seroepidemiology), discovery of the monoclonal antibodies, and development of SARS-CoV-2 (COVID-19) vaccines.

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