IgM and IgG Profiles Reveal Peculiar Features of Humoral Immunity Response to SARS-CoV-2 Infection

The emergence of coronavirus disease 2019 (COVID-19) is globally a major healthcare threat. There is little information regarding the mechanisms and roles of the humoral response in SARS-CoV-2 infection. The aim of this study was to analyze the antibody levels (IgM and IgG) by chemiluminescence immunoassay in 54 subjects positive to SARS-CoV-2 swab test in relation to their clinical status (whether asymptomatic, pauci-symptomatic or with mild, sever or critical symptoms), the time from the symptom onset, sex, age, and comorbidities. Overall, the presence of comorbidities and the age of subjects were associated with their clinical status. The IgG concentrations were significantly higher in patients who developed critical and severe symptoms and seemed to be independent from age, sex and comorbidities. IgG titers peaked around day 60, and then began gradually to drop, decreasing by approximately 50% on the 180th day, while the IgM titers progressively decreased as early as the tenth day, but they could be detected even at later time points. Despite the small number of individuals, some peculiar characteristics of the humoral response in COVID-19 emerged. We observed a high inter-individual variability, an ephemeral IgG half-life in several patients, and a persistence of IgM in others.

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Anti-SARS-CoV-2 antibody levels measured by the Advise Dx SARS-CoV-2 assay are concordant with previously available serologic assays but are not fully predictive of sterilizing immunity

Journal of Clinical Microbiology ◽

10.1128/jcm.00989-21 ◽

2021 ◽

Author(s):

Benjamin T. Bradley ◽

Andrew Bryan ◽

Susan L. Fink ◽

Erin A. Goecker ◽

Pavitra Roychoudhury ◽

...

Keyword(s):

Symptom Onset ◽

Vaccine Dose ◽

Humoral Response ◽

Pcr Detection ◽

Clinical Sensitivity ◽

Significant Difference ◽

Antibody Assays ◽

Unit Conversion ◽

Antibody Levels

With the availability of widespread SARS-CoV-2 vaccination, high-throughput quantitative anti-spike serological testing will likely become increasingly important. Here, we investigated the performance characteristics of the recently FDA authorized semi-quantitative anti-spike AdviseDx SARS-CoV-2 IgG II assay compared to the FDA authorized anti-nucleocapsid Abbott Architect SARS-CoV-2 IgG, Roche elecsys Anti-SARS-CoV-2-S, EuroImmun Anti-SARS-CoV-2 ELISA, and GenScript surrogate virus neutralization assays and examined the humoral response associated with vaccination, natural protection, and breakthrough infection. The AdviseDx assay had a clinical sensitivity at 14 days post-symptom onset or 10 days post PCR detection of 95.6% (65/68, 95% CI: 87.8-98.8%) with two discrepant individuals seroconverting shortly thereafter. The AdviseDx assay demonstrated 100% positive percent agreement with the four other assays examined using the same symptom onset or PCR detection cutoffs. Using a recently available WHO International Standard for anti-SARS-CoV-2 antibody, we provide assay unit conversion factors to international units for each of the assays examined. We performed a longitudinal survey of healthy vaccinated individuals, finding median AdviseDx immunoglobulin levels peaked seven weeks post-first vaccine dose at approximately 4,000 IU/mL. Intriguingly, among the five assays examined, there was no significant difference in antigen binding level or neutralizing activity between two seropositive patients protected against SARS-CoV-2 infection in a previously described fishing vessel outbreak and five healthcare workers who experienced vaccine breakthrough of SARS-CoV-2 infection – all with variants of concern. These findings suggest that protection against SARS-CoV-2 infection cannot currently be predicted exclusively using in vitro antibody assays against wildtype SARS-CoV-2 spike. Further work is required to establish protective correlates for SARS-CoV-2 infection.

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Serological surveillance of SARS-CoV-2: trends and humoral response in a cohort of public health workers

10.1101/2020.10.21.20216689 ◽

2020 ◽

Author(s):

Ross J Harris ◽

Heather J Whitaker ◽

Nick J Andrews ◽

Felicity Aiano ◽

Zahin Amin-Chowdhury ◽

...

Keyword(s):

Half Life ◽

Healthcare Workers ◽

Health Workers ◽

Natural Infection ◽

Humoral Response ◽

Spike Protein ◽

Positive Test ◽

Public Health Workers ◽

Serological Surveillance ◽

Antibody Levels

AbstractBackgroundThere is considerable debate about the rate of antibody waning after SARS-CoV-2 infection, raising questions around long-term immunity following both natural infection and vaccination. We undertook prospective serosurveillance in a large cohort of healthy adults from the start of the epidemic in England.MethodsThe serosurveillance cohort included office and laboratory-based staff and healthcare workers in 4 sites in England, who were tested monthly for SARS-CoV-2 spike protein and nucleoprotein IgG between 23rd March and 20th August 2020. Antibody levels from 21 days after a positive test were modelled using mixed effects regression models.FindingsIn total, 2247 individuals were recruited and 2014 (90%) had 3-5 monthly antibody tests. Overall, 272 (12.1%) of individuals had at least one positive/equivocal spike protein IgG result, with the highest proportion in a hospital site (22%), 14% in London and 2.1% in a rural area. Results were similar for nucleoprotein IgG. Following a positive result, 39/587 (6.6%) tested negative for nucleoprotein IgG and 52/515 (10.1%) for spike protein IgG. Nucleoprotein IgG declined by 6.4% per week (95% CI, 5.5-7.4%; half-life, 75 [95% CI, 66-89] days) and spike protein IgG by 5.8% (95% CI, 5.1-6.6%; half-life, 83 [95% CI, 73-96] days).ConclusionsOver the study period SARS-CoV-2 seropositivity was 8-10% overall and up to 21% in clinical healthcare workers. In seropositive individuals, nucleoprotein and spike protein IgG antibodies declined with time after infection and 50% are predicted to fall below the positive test threshold after 6 months.FundingPHE

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Usefulness of IVD Kits for the Assessment of SARS-CoV-2 Antibodies to Evaluate the Humoral Response to Vaccination

Vaccines ◽

10.3390/vaccines9080840 ◽

2021 ◽

Vol 9 (8) ◽

pp. 840

Author(s):

Krzysztof Lukaszuk ◽

Jolanta Kiewisz ◽

Karolina Rozanska ◽

Malgorzata Dabrowska ◽

Amira Podolak ◽

...

Keyword(s):

Immune Response ◽

Quality Control ◽

Humoral Response ◽

International Standard ◽

Time Points ◽

Igm Antibodies ◽

History Of ◽

Binding Antibody ◽

Antibody Levels

Background: The introduction of the vaccination against SARS-CoV-2 infection creates the need for precise tools for the quality control of vaccination procedures, detection of poor humoral response, and estimation of the achieved protection against the disease. Thus, the study aimed to compare the results of the anti-SARS-CoV-2 tests to evaluate the application of the WHO standard unitage (the binding antibody units; BAU/mL) for a measurement of response to the vaccination. Methods: Patients undergoing vaccination against SARS-CoV-2 with Pfizer/BioNTech BNT162b2 (BNT162b2) (n = 79), referred for SARS-CoV-2 antibody measurement prior to vaccination and 21 days after dose 1, and 8, 14, and 30 days after dose 2 were included. The sera were tested with three assays: Elecsys SARS-CoV-2 S (Roche), LIAISON® SARS-CoV-2 TrimericS IgG (DiaSorin), and SARS-CoV-2 IgG II Quant (Abbott). Results: The three assays showed varying correlations at different time points in the study. The overall agreement for all samples was moderate to high (ρ = 0.663–0.902). We observed the most uniform agreement for the day of dose 2 (ρ = 0.775–0.825), while it was least consistent for day 8 (ρ = −0.131–0.693) and 14 (ρ = −0.247–0.603) after dose 2. The dynamics of changes of the SARS-CoV-2 antibody levels in patients without history of prior SARS-CoV-2 infection appears homogenous based on the Roche results, more heterogenous when considering the DiaSorin results, and in between for the Abbott results. Conclusions: The results highlight the need for further work on the international standard of measurement of SARS-CoV-2 Ig, especially in the era of vaccination. The serological assays can be useful to detect IgG/IgM antibodies to assess the response to the vaccination. However, they cannot be used interchangeably. In terms of the evaluation of the immune response to the BNT162b2 vaccine, Roche and Abbott kits appear to be more useful.

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Sex differences in the decline of neutralizing antibodies to SARS-CoV-2

10.1101/2020.11.12.20230466 ◽

2020 ◽

Cited By ~ 1

Author(s):

Ludivine Grzelak ◽

Aurélie Velay ◽

Yoann Madec ◽

Floriane Gallais ◽

Isabelle Staropoli ◽

...

Keyword(s):

Body Mass Index ◽

Sex Differences ◽

Neutralizing Antibodies ◽

Humoral Response ◽

Time Points ◽

Mild Disease ◽

Duration Of Protection ◽

Antibody Levels ◽

Post Onset ◽

Over Time

The evolution of SARS-CoV-2 humoral response in infected individuals remains poorly characterized. Here, we performed a longitudinal study of sera from 308 RT-qPCR+ individuals with mild disease, collected at two time-points, up to 6 months post-onset of symptoms (POS). We performed two anti-S and one anti-N serology assays and quantified neutralizing antibodies (NAbs). At month 1 (M1), males, individuals > 50 years of age or with a body mass index (BMI) > 25 exhibited higher levels of antibodies. Antibody levels decreased over time. At M3-6, anti-S antibodies persisted in 99% of individuals while anti-N IgG were measurable in only 59% of individuals. The decline in anti-S and NAbs was faster in males than in females, independently of age and BMI. Our results show that some serology tests are less reliable overtime and suggest that the duration of protection after SARS-CoV-2 infection or vaccination will be different in women and men.

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Anti-SARS-CoV-2 antibody levels are concordant across multiple platforms but are not fully predictive of sterilizing immunity

10.1101/2021.04.26.21256118 ◽

2021 ◽

Author(s):

Benjamin T. Bradley ◽

Andrew Bryan ◽

Susan L. Fink ◽

Erin A. Goecker ◽

Pavitra Roychoudhury ◽

...

Keyword(s):

Symptom Onset ◽

Vaccine Dose ◽

Humoral Response ◽

Pcr Detection ◽

Clinical Sensitivity ◽

Significant Difference ◽

Antibody Assays ◽

Unit Conversion ◽

Antibody Levels

AbstractWith the availability of widespread SARS-CoV-2 vaccination, high-throughput quantitative anti-spike serological testing will likely become increasingly important. Here, we investigated the performance characteristics of the recently FDA authorized semi-quantitative anti-spike AdviseDx SARS-CoV-2 IgG II assay compared to the FDA authorized anti-nucleocapsid Abbott Architect SARS-CoV-2 IgG, Roche elecsys Anti-SARS-CoV-2-S, EuroImmun Anti-SARS-CoV-2 ELISA, and GenScript surrogate virus neutralization assays and examined the humoral response associated with vaccination, natural protection, and breakthrough infection. The AdviseDx assay had a clinical sensitivity at 14 days post-symptom onset or 10 days post PCR detection of 95.6% (65/68, 95% CI: 87.8-98.8%) with two discrepant individuals seroconverting shortly thereafter. The AdviseDx assay demonstrated 100% positive percent agreement with the four other assays examined using the same symptom onset or PCR detection cutoffs. Using a recently available WHO International Standard for anti-SARS-CoV-2 antibody, we provide assay unit conversion factors to international units for each of the assays examined. We performed a longitudinal survey of healthy vaccinated individuals, finding median AdviseDx immunoglobulin levels peaked seven weeks post-first vaccine dose at approximately 4,000 IU/mL. Intriguingly, among the five assays examined, there was no significant difference in antigen binding level or neutralizing activity between two seropositive patients protected against SARS-CoV-2 infection in a previously described fishing vessel outbreak and five healthcare workers who experienced vaccine breakthrough of SARS-CoV-2 infection – all with variants of concern. These findings suggest that protection against SARS-CoV-2 infection cannot currently be predicted exclusively using in vitro antibody assays against wildtype SARS-CoV-2 spike. Further work is required to establish protective correlates of protection for SARS-CoV-2 infection.

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

Viruses ◽

10.3390/v13071244 ◽

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.

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Survival in Early Breast Cancer Patients Is Favorably Influenced by a Natural Humoral Immune Response to Polymorphic Epithelial Mucin

Journal of Clinical Oncology ◽

10.1200/jco.2000.18.3.574 ◽

2000 ◽

Vol 18 (3) ◽

pp. 574-574 ◽

Cited By ~ 153

Author(s):

S. von Mensdorff-Pouilly ◽

A.A. Verstraeten ◽

P. Kenemans ◽

F.G. M. Snijdewint ◽

A. Kok ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Patients ◽

Early Breast Cancer ◽

Humoral Response ◽

Disease Specific Survival ◽

Breast Cancer Patients ◽

Antibody Levels ◽

Pretreatment Serum ◽

Test Result ◽

Disease Specific

PURPOSE: Polymorphic epithelial mucin (PEM or MUC1) is being studied as a vaccine substrate for the immunotherapy of patients with adenocarcinoma. The present study analyzes the incidence of naturally occurring MUC1 antibodies in early breast cancer patients and relates the presence of these antibodies in pretreatment serum to outcome of disease.MATERIALS AND METHODS: We measured immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies to MUC1 with an enzyme-linked immunoassay (PEM.CIg), which uses a MUC1 triple-tandem repeat peptide conjugated to bovine serum albumin, in pretreatment serum samples obtained from 154 breast cancer patients (52 with stage I disease and 102 with stage II) and 302 controls. The median disease-specific survival time of breast cancer patients was 74 months (range, 15 to 118 months). A positive test result was defined as MUC1 IgG or IgM antibody levels equal to or greater than the corresponding rounded-up median results obtained in the total breast cancer population.RESULTS: A positive test result for both MUC1 IgG and IgM antibodies in pretreatment serum was associated with a significant benefit in disease-specific survival in stage I and II (P = .0116) breast cancer patients. Positive IgG and IgM MUC1 antibody levels had significant additional prognostic value to stage (P = .0437) in multivariate analysis. Disease-free survival probability did not differ significantly. However, stage II patients who tested positive for MUC1 IgG and IgM antibody and who relapsed had predominantly local recurrences or contralateral disease, as opposed to recurrences at distant sites in the patients with a negative humoral response (P = .026).CONCLUSION: Early breast cancer patients with a natural humoral response to MUC1 have a higher probability of freedom from distant failure and a better disease-specific survival. MUC1 antibodies may control hematogenic tumor dissemination and outgrowth by aiding the destruction of circulating or seeded MUC1-expressing tumor cells. Vaccination of breast cancer patients with MUC1-derived (glyco)peptides in an adjuvant setting may favorably influence the outcome of disease.

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Longterm Efficacy of an Antipneumococcal Polysaccharide Vaccine among Patients with Autoimmune Inflammatory Rheumatic Diseases

The Journal of Rheumatology ◽

10.3899/jrheum.150397 ◽

2016 ◽

Vol 43 (2) ◽

pp. 267-272 ◽

Cited By ~ 14

Author(s):

Adi Broyde ◽

Uri Arad ◽

Noa Madar-Balakirski ◽

Daphna Paran ◽

Ilana Kaufman ◽

...

Keyword(s):

Humoral Response ◽

Polysaccharide Vaccine ◽

Inflammatory Rheumatic Diseases ◽

Technical Problems ◽

Tnf Α ◽

Antibody Titers ◽

Inflammatory Bowel ◽

Factor Α ◽

Antibody Levels ◽

Necrosis Factor

Objective.To estimate the longterm humoral response of an antipneumococcal polysaccharide vaccine (PPSV23) in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS), or inflammatory bowel disease (IBD)-associated spondyloarthropathy (SpA), and the effect of demographic and clinical factors and treatment on the longterm efficacy of the vaccine.Methods.A total of 145 consecutive patients treated with biologics [tumor necrosis factor-α (TNF-α) or interleukin 6 (IL-6) receptor inhibitors] or methotrexate (MTX) participated in this study. Fifteen were excluded because of absent information regarding their vaccination status (n = 9) or because of technical problems in obtaining their serum sample (n = 6). They were diagnosed with RA (n = 63, 48.5%), PsA (n = 29, 22.3%), AS (n = 28, 21.5%), or IBD-associated SpA (n = 3, 2.3%). Their mean age was 54.6 years, and 61.5% were women. Data were collected on the timing of vaccination, demographic and clinical characteristics, and treatment, and patients’ serum antipneumococcal antibody levels were tested.Results.Two-thirds of the patients (67.7%) had received PPSV23 45 months (mean) earlier. Treatment included TNF-α inhibitors (73.9%), IL-6 receptor inhibitors (13.1%), or MTX without a biological treatment (13%). The uptake of vaccination was significantly higher in the older population (> 65 yrs). Vaccinated patients had significantly higher antibody levels compared with vaccine-naive patients. The antibody levels had been preserved after 10 years. MTX use, but not biologics, was associated with significantly lower antibody levels.Conclusion.The longterm efficacy of the PPSV23 vaccination seems to be preserved among patients with RA, PsA, AS, and IBD-associated SpA for at least 10 years. Efficacy is slightly impaired by MTX, but it is not affected by biologics. These findings suggest that revaccination after 5 years might not be needed for all, and testing the antibody titers should be considered to identify those who may benefit from revaccination.

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Biologic variability of N-terminal pro-brain natriuretic peptide in adult healthy cats

Journal of Feline Medicine and Surgery ◽

10.1177/1098612x15623825 ◽

2016 ◽

Vol 19 (2) ◽

pp. 216-223 ◽

Cited By ~ 9

Author(s):

Autumn N Harris ◽

Amara H Estrada ◽

Alexander E Gallagher ◽

Brandy Winter ◽

Kenneth E Lamb ◽

...

Keyword(s):

Brain Natriuretic Peptide ◽

Natriuretic Peptide ◽

Cardiac Disease ◽

Complete Blood Count ◽

Individual Variability ◽

P Value ◽

Time Points ◽

Total Thyroxine ◽

Index Of Individuality ◽

Adult Cats

Objectives The biologic variability of N-terminal pro-brain natriuretic peptide (NT-proBNP) and its impact on diagnostic utility is unknown in healthy cats and those with cardiac disease. The purpose of this study was to determine the biologic variation of NT-proBNP within-day and week-to-week in healthy adult cats. Methods Adult cats were prospectively evaluated by complete blood count (CBC), biochemistry, total thyroxine, echocardiography, electrocardiography and blood pressure, to exclude underlying systemic or cardiac disease. Adult healthy cats were enrolled and blood samples were obtained at 11 time points over a 6 week period (0, 2 h, 4 h, 6 h, 8 h, 10 h and at weeks 2, 3, 4, 5 and 6). The intra-individual (coefficient of variation [CVI]) biologic variation along with index of individuality and reference change values (RCVs) were calculated. Univariate models were analyzed and included comparison of the six different time points for both daily and weekly samples. This was followed by a Tukey’s post-hoc adjustment, with a P value of <0.05 being significant. Results The median daily and weekly CVI for the population were 13.1% (range 0–28.7%) and 21.2% (range 3.9–68.1%), respectively. The index of individuality was 0.99 and 1 for daily and weekly samples, respectively. The median daily and weekly RCVs for the population were 39.8% (range 17.0–80.5%) and 60.5% (range 20.1–187.8%), respectively. Conclusions and relevance This study demonstrates high individual variability for NT-proBNP concentrations in a population of adult healthy cats. Further research is warranted to evaluate NT-proBNP variability, particularly how serial measurements of NT-proBNP may be used in the diagnosis and management of cats with cardiac disease.

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DNA vaccines expressing pneumococcal surface protein A (PspA) elicit protection levels comparable to recombinant protein

Journal of Medical Microbiology ◽

10.1099/jmm.0.46217-0 ◽

2006 ◽

Vol 55 (4) ◽

pp. 375-378 ◽

Cited By ~ 14

Author(s):

Daniela M. Ferreira ◽

Eliane N. Miyaji ◽

Maria Leonor S. Oliveira ◽

Michelle Darrieux ◽

Ana Paula M. Arêas ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Recombinant Protein ◽

Dna Vaccines ◽

Protein A ◽

Surface Protein ◽

Humoral Response ◽

Cost Effective ◽

Promising Candidate ◽

Pneumococcal Surface Protein A ◽

Antibody Levels

Pneumococcal surface protein A (PspA) is a promising candidate for the development of cost-effective vaccines against Streptococcus pneumoniae. In the present study, BALB/c mice were immunized with DNA vaccine vectors expressing the N-terminal region of PspA. Animals immunized with a vector expressing secreted PspA developed higher levels of antibody than mice immunized with the vector expressing the antigen in the cytosol. However, both immunogens elicited similar levels of protection against intraperitoneal challenge. Furthermore, immunization with exactly the same fragment in the form of a recombinant protein, with aluminium hydroxide as an adjuvant, elicited even higher antibody levels, but this increased humoral response did not correlate with enhanced protection. These results show that DNA vaccines expressing PspA are able to elicit protection levels comparable to recombinant protein, even though total anti-PspA IgG response is considerably lower.

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