Longitudinal Serological Analysis and Neutralizing Antibody Levels in Coronavirus Disease 2019 Convalescent Patients

Abstract Background Understanding the longitudinal trajectory of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies is crucial for diagnosis of prior infection and predicting future immunity. Methods We conducted a longitudinal analysis of coronavirus disease 2019 convalescent patients, with neutralizing antibody assays and SARS-CoV-2 serological assay platforms using SARS-CoV-2 spike (S) or nucleocapsid (N) antigens. Results Sensitivities of serological assays in diagnosing prior SARS-CoV-2 infection changed with time. One widely used commercial platform that had an initial sensitivity of >95% declined to 71% at 81–100 days after diagnosis. The trajectories of median binding antibody titers measured over approximately 3–4 months were not dependent on the use of SARS-CoV-2 N or S proteins as antigen. The median neutralization titer decreased by approximately 45% per month. Each serological assay gave quantitative antibody titers that were correlated with SARS-CoV-2 neutralization titers, but S-based serological assay measurements better predicted neutralization potency. Correlation between S-binding and neutralization titers deteriorated with time, and decreases in neutralization titers were not predicted by changes in S-binding antibody titers. Conclusions Different SARS-CoV-2 serological assays are more or less well suited for surveillance versus prediction of serum neutralization potency. Extended follow-up should facilitate the establishment of appropriate serological correlates of protection against SARS-CoV-2 reinfection.

Download Full-text

Sex disparities and neutralizing antibody durability to SARS-CoV-2 infection in convalescent individuals

10.1101/2021.02.01.21250493 ◽

2021 ◽

Author(s):

Alena J. Markmann ◽

Natasa Giallourou ◽

D. Ryan Bhowmik ◽

Yixuan J. Hou ◽

Aaron Lerner ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Neutralizing Antibody ◽

Antibody Responses ◽

Human Antibody ◽

Antibody Titers ◽

Sex Disparities ◽

Binding Antibody ◽

Male Sex ◽

Antibody Levels ◽

First Time

AbstractThe coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) has now caused over 2 million deaths worldwide and continues to expand. Currently, much is unknown about functionally neutralizing human antibody responses and durability to SARS-CoV-2. Using convalescent sera collected from 101 COVID-19 recovered individuals 21-212 days after symptom onset with forty-eight additional longitudinal samples, we measured functionality and durability of serum antibodies. We also evaluated associations between individual demographic and clinical parameters with functional neutralizing antibody responses to COVID-19. We found robust antibody durability out to six months, as well as significant positive associations with the magnitude of the neutralizing antibody response and male sex. We also show that SARS-CoV-2 convalescent neutralizing antibodies are higher in individuals with cardio-metabolic comorbidities.SignificanceIn this study we found that neutralizing antibody responses in COVID-19 convalescent individuals vary in magnitude but are durable and correlate well with RBD Ig binding antibody levels compared to other SARS-CoV-2 antigen responses. In our cohort, higher neutralizing antibody titers are independently and significantly associated with male sex compared to female sex. We also show for the first time, that higher convalescent antibody titers in male donors are associated with increased age and symptom grade. Furthermore, cardio-metabolic co-morbidities are associated with higher antibody titers independently of sex. Here, we present an in-depth evaluation of serologic, demographic, and clinical correlates of functional antibody responses and durability to SARS-CoV-2.

Download Full-text

Sex Disparities and Neutralizing-Antibody Durability to SARS-CoV-2 Infection in Convalescent Individuals

mSphere ◽

10.1128/msphere.00275-21 ◽

2021 ◽

Vol 6 (4) ◽

Author(s):

Alena J. Markmann ◽

Natasa Giallourou ◽

D. Ryan Bhowmik ◽

Yixuan J. Hou ◽

Aaron Lerner ◽

...

Keyword(s):

Receptor Binding ◽

Neutralizing Antibody ◽

Binding Domain ◽

Antibody Responses ◽

Receptor Binding Domain ◽

Antibody Titers ◽

Sex Disparities ◽

Binding Antibody ◽

Male Sex ◽

Antibody Levels

In this study, we found that neutralizing antibody responses in COVID-19-convalescent individuals vary in magnitude but are durable and correlate well with receptor binding domain (RBD) Ig binding antibody levels compared to other SARS-CoV-2 antigen responses. In our cohort, higher neutralizing antibody titers are independently and significantly associated with male sex compared to female sex.

Download Full-text

An Anti-Nucleocapsid Antigen Sars-Cov-2 Total Antibody Assay Finds Comparable Results in Edta-Anticoagulated Whole Blood Obtained from Capillary and Venous Blood Sampling

Data ◽

10.3390/data5040105 ◽

2020 ◽

Vol 5 (4) ◽

pp. 105

Author(s):

Martin Risch ◽

Marc Kovac ◽

Corina Risch ◽

Dorothea Hillmann ◽

Michael Ritzler ◽

...

Keyword(s):

Whole Blood ◽

Venous Blood ◽

Capillary Blood ◽

Blood Sampling ◽

Attractive Alternative ◽

Antibody Assay ◽

Antibody Assays ◽

Antibody Titers ◽

Antibody Levels ◽

Venous Blood Sampling

Although SARS-CoV-2 antibody assays have been found to provide valid results in EDTA-anticoagulated whole blood, so far, they have not demonstrated that antibody levels in whole blood originating from capillary blood samples are comparable to antibody levels measured in blood from a venous origin. Here, blood is drawn simultaneously by capillary and venous blood sampling. Antibody titers are determined by an assay employing electrochemiluminescence (ECLIA) and SARS-CoV-2 total immunoglobulins are detected with specificity directed against the nucleocapsid antigen. Six individuals with confirmed COVID-19 and six individuals without COVID-19 are analyzed. Antibody titers in capillary venous whole blood did not show significant differences, and when corrected for hematocrit, they did not differ from the results obtained from serum. In conclusion, capillary sampled EDTA-anticoagulated whole blood seems to be an attractive alternative matrix for the evaluation of SARS-CoV-2 antibodies when employing ECLIA for detecting total antibodies directed against nucleocapsid antibodies.

Download Full-text

SARS-CoV-2 Convalescent Sera Binding and Neutralizing Antibody Concentrations Compared with COVID-19 Vaccine Efficacy Estimates Against Symptomatic Infection

10.1101/2021.11.24.21266812 ◽

2021 ◽

Author(s):

Amy J. Schuh ◽

Panayampalli S. Satheshkumar ◽

Stephanie Dietz ◽

Lara Bull-Otterson ◽

Myrna Charles ◽

...

Keyword(s):

Vaccine Efficacy ◽

Neutralizing Antibody ◽

Published Data ◽

Symptomatic Infection ◽

Convenience Sample ◽

Post Vaccination ◽

Antibody Assays ◽

Study Population ◽

Binding Antibody ◽

Induced Immunity

Previous vaccine efficacy (VE) studies have estimated neutralizing and binding antibody concentrations that correlate with protection from symptomatic infection; how these estimates compare to those generated in response to SARS-CoV-2 infection is unclear. Here, we assessed quantitative neutralizing and binding antibody concentrations using standardized SARS-CoV-2 assays on 3,067 serum specimens collected during July 27, 2020-August 27, 2020 from COVID-19 unvaccinated persons with detectable anti-SARS-CoV-2 antibodies using qualitative antibody assays. Quantitative neutralizing and binding antibody concentrations were strongly positively correlated (r=0.76, p<0.0001) and were noted to be several fold lower in the unvaccinated study population as compared to published data on concentrations noted 28 days post-vaccination. In this convenience sample, ~88% of neutralizing and ~63-86% of binding antibody concentrations met or exceeded concentrations associated with 70% COVID-19 VE against symptomatic infection from published VE studies; ~30% of neutralizing and 1-14% of binding antibody concentrations met or exceeded concentrations associated with 90% COVID-19 VE. These data support observations of infection-induced immunity and current recommendations for vaccination post infection to maximize protection against symptomatic COVID-19.

Download Full-text

Age-Dependent Evaluation of Immunoglobulin G Response after Chikungunya Virus Infection

American Journal of Tropical Medicine and Hygiene ◽

10.4269/ajtmh.20-1398 ◽

2021 ◽

Author(s):

Harshad P. Patil ◽

Mrunal Gosavi ◽

Akhilesh C. Mishra ◽

Vidya A. Arankalle

Keyword(s):

Acute Phase ◽

Chikungunya Virus ◽

Indirect Elisa ◽

Neutralizing Antibody ◽

Antibody Prevalence ◽

Exposure Age ◽

Age Dependent ◽

Antibody Titers ◽

Binding Antibody ◽

Acute Phase Serum

Current chikungunya antibody prevalence and titers are likely to differ based on exposure rates before the 2006 reemergence. For vaccine usage, such data are of immense importance. This study addresses age-stratified IgG titers and its subtypes in Pune, India, endemic for the disease. One hundred seventy serum pools (791 individuals with prior chikungunya exposure, age stratified) from exposed and 15 samples from acute disease phase were screened. Inactivated chikungunya virus (CHIKV)–based indirect ELISA was used to determine anti–CHIKV-IgG and its subtypes. Neutralizing antibody titers (plaque reduction neutralization test [PRNT]) were compared with binding antibody titers (ELISA). Anti–CHIKV-IgG titers along with IgG1 and IgG4 increased till the age-group of 11–15 years and remained comparable thereafter till > 65 years. IgG1 was the predominant IgG subtype detected in all the pools, whereas IgG4 was present in 151/170 pools. Strong correlation of IgG1 was obtained with CHIKV–PRNT50 titers. None of the sample had anti–CHIKV-IgG2, whereas five pools had IgG3 antibody. In the acute-phase serum sample, IgG1 was present in all the samples, whereas IgG4 was present in 8/15 samples. IgG4 was predominant in four samples. During acute phase and at different times postinfection, IgG1 circulated in high titers followed by IgG4. Higher antibody titers in adults reflect reexposures. The data will prove useful in assessing immune response to CHIKV vaccine.

Download Full-text

Persistence of Antibodies to 2 Virus-Like Particle Norovirus Vaccine Candidate Formulations in Healthy Adults: 1-Year Follow-up With Memory Probe Vaccination

The Journal of Infectious Diseases ◽

10.1093/infdis/jiz170 ◽

2019 ◽

Vol 220 (4) ◽

pp. 603-614 ◽

Cited By ~ 6

Author(s):

Robert L Atmar ◽

Frank Baehner ◽

Jakob P Cramer ◽

Eric Lloyd ◽

James Sherwood ◽

...

Keyword(s):

Vaccine Candidate ◽

Immunoglobulin A ◽

Primary Vaccination ◽

Immune Memory ◽

Virus Like Particle ◽

Memory Probe ◽

Antibody Titers ◽

Antibody Levels ◽

With Memory

AbstractBackgroundWe previously reported the tolerability and immunogenicity 1 month after intramuscular administration of 2 bivalent virus-like particle (VLP)–based candidate norovirus vaccine formulations in adults. We now describe the persistence of immunity and responses to a memory probe vaccination 1 year later.MethodsA total of 454 healthy men and women aged 18–49 years in 3 equal groups received placebo (saline) or 15/50 or 50/50 vaccine formulations (ie, 15 or 50 µg of GI.1 genotype VLPs, respectively, and 50 µg of GII.4c VLPs) with MPL and Al(OH)3. Immunogenicity and safety were assessed up to day 365, when 351 participants received a memory probe vaccination of 15 µg each of GI.1 and GII.4c VLPs with Al(OH)3.ResultsNo safety signals were detected up to 1 year after the first vaccination. Pan-immunoglobulin, immunoglobulin A, and histo-blood group antigen–blocking (HBGA) antibody levels among vaccinees waned but remained higher than levels before vaccination and levels in placebo recipients on days 180 and 365. Memory probe vaccination increased all antibody titers. Levels of HBGA antibodies to GI.1 but not GII.4c were higher after the first vaccination in candidate vaccine groups, compared with those in the placebo group.ConclusionLevels of antibodies to both candidate norovirus VLP formulations persisted above baseline levels for at least 1 year after primary vaccination. HBGA-blocking responses to the memory probe for GI.1 but not GII.4c displayed characteristics of immune memory.Clinical Trials RegistrationNCT02142504.

Download Full-text

Neutralizing Antibody Responses in COVID-19 Convalescent Sera

The Journal of Infectious Diseases ◽

10.1093/infdis/jiaa673 ◽

2020 ◽

Vol 223 (1) ◽

pp. 47-55 ◽

Cited By ~ 1

Author(s):

William T Lee ◽

Roxanne C Girardin ◽

Alan P Dupuis ◽

Karen E Kulas ◽

Anne F Payne ◽

...

Keyword(s):

Neutralizing Antibodies ◽

High Titer ◽

Experimental Treatment ◽

Neutralizing Antibody ◽

Maximal Activity ◽

The United States ◽

Enzyme Linked Immunosorbent Assay ◽

United States Food ◽

Antibody Titers ◽

Antibody Levels

Abstract Passive transfer of antibodies from COVID-19 convalescent patients is being used as an experimental treatment for eligible patients with SARS-CoV-2 infections. The United States Food and Drug Administration’s (FDA) guidelines for convalescent plasma initially recommended target antibody titers of 160. We evaluated SARS-CoV-2 neutralizing antibodies in sera from recovered COVID-19 patients using plaque reduction neutralization tests (PRNT) at moderate (PRNT50) and high (PRNT90) stringency thresholds. We found that neutralizing activity significantly increased with time post symptom onset (PSO), reaching a peak at 31–35 days PSO. At this point, the number of sera having neutralizing titers of at least 160 was approximately 93% (PRNT50) and approximately 54% (PRNT90). Sera with high SARS-CoV-2 antibody levels (>960 enzyme-linked immunosorbent assay titers) showed maximal activity, but not all high-titer sera contained neutralizing antibody at FDA recommended levels, particularly at high stringency. These results underscore the value of serum characterization for neutralization activity.

Download Full-text

Functional antibody and T-cell immunity following SARS-CoV-2 infection, including by variants of concern, in patients with cancer: the CAPTURE study

10.21203/rs.3.rs-916427/v1 ◽

2021 ◽

Author(s):

Annika Fendler ◽

Lewis Au ◽

Scott Shepherd ◽

Fiona Byrne ◽

Maddalena Cerrone ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Neutralizing Antibody ◽

Cellular Responses ◽

Patients With Cancer ◽

Cell Immunity ◽

Clinical Annotation ◽

Antibody Titers ◽

Antibody Levels ◽

Immune Profiling ◽

Reactive Antibody

Abstract Patients with cancer have higher COVID-19 morbidity and mortality. Here we present the prospective CAPTURE study (NCT03226886) integrating longitudinal immune profiling with clinical annotation. Of 357 patients with cancer, 118 were SARS-CoV-2-positive, 94 were symptomatic and 2 patients died of COVID-19. In this cohort, 83% patients had S1-reactive antibodies, 82% had neutralizing antibodies against WT, whereas neutralizing antibody titers (NAbT) against the Alpha, Beta, and Delta variants were substantially reduced. Whereas S1-reactive antibody levels decreased in 13% of patients, NAbT remained stable up to 329 days. Patients also had detectable SARS-CoV-2-specific T cells and CD4+ responses correlating with S1-reactive antibody levels, although patients with hematological malignancies had impaired immune responses that were disease and treatment-specific, but presented compensatory cellular responses, further supported by clinical. Overall, these findings advance the understanding of the nature and duration of immune response to SARS-CoV-2 in patients with cancer.

Download Full-text

A SARS-CoV-2 spike ferritin nanoparticle vaccine protects hamsters against Alpha and Beta virus variant challenge

npj Vaccines ◽

10.1038/s41541-021-00392-7 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Kathryn McGuckin Wuertz ◽

Erica K. Barkei ◽

Wei-Hung Chen ◽

Elizabeth J. Martinez ◽

Ines Lakhal-Naouar ◽

...

Keyword(s):

Neutralizing Antibody ◽

High Dose ◽

Lung Pathology ◽

Vaccine Protection ◽

Virus Variant ◽

Syrian Golden Hamsters ◽

Antibody Titers ◽

Binding Antibody ◽

Adequate Coverage ◽

Dose Dependent

AbstractThe emergence of SARS-CoV-2 variants of concern (VOC) requires adequate coverage of vaccine protection. We evaluated whether a SARS-CoV-2 spike ferritin nanoparticle vaccine (SpFN), adjuvanted with the Army Liposomal Formulation QS21 (ALFQ), conferred protection against the Alpha (B.1.1.7), and Beta (B.1.351) VOCs in Syrian golden hamsters. SpFN-ALFQ was administered as either single or double-vaccination (0 and 4 week) regimens, using a high (10 μg) or low (0.2 μg) dose. Animals were intranasally challenged at week 11. Binding antibody responses were comparable between high- and low-dose groups. Neutralizing antibody titers were equivalent against WA1, B.1.1.7, and B.1.351 variants following two high dose vaccinations. Dose-dependent SpFN-ALFQ vaccination protected against SARS-CoV-2-induced disease and viral replication following intranasal B.1.1.7 or B.1.351 challenge, as evidenced by reduced weight loss, lung pathology, and lung and nasal turbinate viral burden. These data support the development of SpFN-ALFQ as a broadly protective, next-generation SARS-CoV-2 vaccine.

Download Full-text

Detection, prevalence, and duration of humoral responses to SARS-CoV-2 under conditions of limited population exposure.

10.1101/2020.08.14.20174490 ◽

2020 ◽

Cited By ~ 6

Author(s):

Tyler J Ripperger ◽

Jennifer L Uhrlaub ◽

Makiko Watanabe ◽

Rachel Wong ◽

Yvonne Castaneda ◽

...

Keyword(s):

Local Community ◽

Severe Disease ◽

Neutralizing Antibody ◽

Population Level ◽

Population Exposure ◽

Antibody Titers ◽

Asymptomatic Individuals ◽

Humoral Responses ◽

Antibody Levels ◽

Antibody Kinetics

We conducted an extensive serological study to quantify population-level exposure and define correlates of immunity against SARS-CoV-2. We found that relative to mild COVID-19 cases, individuals with severe disease exhibited elevated authentic virus-neutralizing titers and antibody levels against nucleocapsid (N) and the receptor binding domain (RBD) and the S2 region of spike protein. Unlike disease severity, age and sex played lesser roles in serological responses. All cases, including asymptomatic individuals, seroconverted by 2 weeks post-PCR confirmation. RBD- and S2-specific and neutralizing antibody titers remained elevated and stable for at least 2-3 months post-onset, whereas those against N were more variable with rapid declines in many samples. Testing of 5882 self-recruited members of the local community demonstrated that 1.24% of individuals showed antibody reactivity to RBD. However, 18% (13/73) of these putative seropositive samples failed to neutralize authentic SARS-CoV-2 virus. Each of the neutralizing, but only 1 of the non-neutralizing samples, also displayed potent reactivity to S2. Thus, inclusion of multiple independent assays markedly improved the accuracy of antibody tests in low seroprevalence communities and revealed differences in antibody kinetics depending on the viral antigen. In contrast to other reports, we conclude that immunity is durable for at least several months after SARS-CoV-2 infection.

Download Full-text