SARS‐CoV‐2 infections among pregnant women, 2020, Finland—Cross‐testing of neutralization assays

Journal of Medical Virology, Journal Year: 2024, Volume and Issue: 96(2)

Published: Jan. 31, 2024

Abstract We studied the development of severe acute respiratory syndrome‐related coronavirus (SARS‐CoV‐2) pandemic in southern Finland 2020 and evaluated performance two surrogate immunoassays for detection neutralizing antibodies (NAbs). The data set consisted 12 000 retrospectively collected samples from pregnant women their first trimester throughout 2020. All were initially screened immunoglobulin G (IgG) with SARS‐CoV‐2 spike antibody assay (EIM‐S1, Euroimmun) followed by confirmation nucleocapsid (Architect SARS‐CoV‐2, Abbott). Samples that reactive (positive or borderline) both assays subjected to testing commercial NeutraLISA (EIM) cPass TM (GenScript Biotech Corporation) using pseudoneutralization (PNAbA) as a golden standard. No seropositive cases detected between January March. Between April December, IgG (EIM‐S1 Abbott positive) NAb (PNAbA seroprevalences 0.4% 1.4%. showed 90% 55% concordant results PNAbA among negative 49% 92% positive giving better specificity but lower sensitivity than cPass. To conclude, seroprevalence reflected general population variability serological protocols needs be taken into account inter‐study comparison.

Language: Английский

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tANCHOR-cell-based assay for monitoring of SARS-CoV-2 neutralizing antibodies rapidly adaptive to various receptor-binding domains

iScience, Journal Year: 2024, Volume and Issue: 27(3), P. 109123 - 109123

Published: Feb. 5, 2024

Conventional neutralizing enzyme-linked immunosorbent assay (ELISA) systems for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mimic the protein-protein interaction between angiotensin-converting enzyme (ACE2) and receptor-binding domain (RBD). However, an easy rapidly adaptative ELISA-based system testing antibodies against upcoming SARS-CoV-2 variants is urgently needed. In this study, we closed gap by developing a tANCHOR-cell-based RBD neutralization that avoids time-consuming protein expression purification followed coating on ELISA plates. This cell-based can be adopted to monitor (NAbs) variants. We show results obtained with strongly correlate commercially available surrogate assays NAbs. Moreover, technique directly measure binding cell-surface-exposed RBDs soluble ACE2. With technique, degree of antibody escape elicited emerging in current vaccination regimens determined reliably.

Language: Английский

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Utility of accessible SARS-CoV-2 specific immunoassays in vaccinated adults with a history of advanced HIV infection

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: April 9, 2024

Abstract Accessible SARS-CoV-2-specific immunoassays may inform clinical management in people with HIV, particularly case of persisting immunodysfunction. We prospectively studied their application vaccine recipients purposely including participants a history advanced HIV infection. Participants received one (n = 250), two 249) or three 42) doses the BNT162b2 vaccine. Adverse events were documented through questionnaires. Sample collection occurred pre-vaccination and median 4 weeks post-second dose 14 post-third dose. Anti-spike anti-nucleocapsid antibodies measured Roche Elecsys chemiluminescence immunoassays. Neutralising activity was evaluated using GenScript cPass surrogate virus neutralisation test, following validation against Plaque Reduction Neutralization Test. T-cell reactivity assessed SARS-CoV-2 IFNγ release assay. Primary vaccination (2 doses) well tolerated elicited measurable anti-spike 202/206 (98.0%) participants. titres varied widely, influenced by previous exposure, ethnicity, intravenous drug use, CD4 counts viremia as independent predictors. A third significantly boosted neutralising responses, reducing variability. > 15 U/mL correlated 136/144 paired samples (94.4%). Three detectable anti-S did not develop responses dose, yet displayed specific responses. is well-tolerated immunogenic adults improving serve reliable indicator activity. Discordances between accompanied IFN-γ underlining complexity immune response this population.

Language: Английский

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Survey of severe acute respiratory syndrome coronavirus 2 in captive and free-ranging wildlife from Spain

Veterinary Research, Journal Year: 2024, Volume and Issue: 55(1)

Published: July 19, 2024

Abstract Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), considered a zoonotic agent of wildlife origin, can infect various animal species, including in free-range and captive environments. Detecting susceptible species potential reservoirs is crucial for preventing the transmission, spread, genetic evolution, further emergence viral variants that are major threats to global health. This study aimed detect exposure or infection by SARS-CoV-2 420 animals from 40 different terrestrial aquatic mammals, regions Spain during 2020–2023 disease 19 (COVID-19) pandemic. In total, 8/137 were positive antibodies against receptor binding domain and/or nucleoprotein according independent ELISAs. However, only one ELISA-positive sample bottlenose dolphin ( Tursiops truncatus ) tested neutralizing with low titre (SNT 50 38.15) virus neutralization test. Cetaceans expected have high risk early predictive studies due similarity their angiotensin converting enzyme cell humans. Moreover, 283 analysed RNA using RT-qPCR, none positive. Our results reinforce importance considering cetaceans at support taking preventive biosecurity measures when interacting them, especially presence individuals suspected confirmed COVID-19. Although most this negative exposure, ongoing surveillance potentially important prevent future spillover events novel reservoirs.

Language: Английский

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Surrogate Virus Neutralisation Test Based on Nanoluciferase-Tagged Antigens to Quantify Inhibitory Antibodies against SARS-CoV-2 and Characterise Omicron-Specific Reactivity in a Vaccination Cohort

Vaccines, Journal Year: 2023, Volume and Issue: 11(12), P. 1832 - 1832

Published: Dec. 8, 2023

Virus-specific antibodies are crucial for protective immunity against SARS-CoV-2. Assessing functional through conventional or pseudotyped virus neutralisation tests (pVNT) requires high biosafety levels. Alternatively, the virus-free surrogate test (sVNT) quantifies interfering with spike binding to angiotensin-converting enzyme 2. We evaluated secreted nanoluciferase-tagged protein fragments as diagnostic antigens in sVNT a vaccination cohort. Initially, were tested capture immunoassay (EIA), identifying receptor domain (RBD) optimal antigen. The sensitivity of in-house applying nanoluciferase-labelled RBD equalled surpassed that commercial (cPass, GenScript Diagnostics) and an pVNT four weeks after first (98% vs. 94% 72%, respectively), reaching 100% all assays second third vaccinations. When testing serum reactivity Omicron BA.1 spike, displayed superior discrimination between wild-type- variant-specific compared EIA. This was most pronounced vaccinations, resulting robust, cross-reactive construct detection. In conclusion, utilising permits quantification SARS-CoV-2-specific inhibitory antibodies. Designed flexible modular systems, can be readily adjusted monitoring vaccine efficacy.

Language: Английский

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Longitudinal neutralizing antibody responses after SARS-CoV-2 infection: A convalescent cohort study in Taiwan

Journal of Microbiology Immunology and Infection, Journal Year: 2023, Volume and Issue: 56(3), P. 506 - 515

Published: March 16, 2023

Understanding the neutralizing antibody (NAb) titer against COVID-19 over time is important to provide information for vaccine implementation. The longitudinal NAb one year after SARS-CoV-2 infection still unclear. purposes of this study are evaluate duration titers in convalescents and factors associated with positive duration. A cohort followed individuals diagnosed between 2020 2021 May 15th from database Taiwan Centers Disease Control. We analyzed convalescent individuals. used generalized estimating equations (GEE) a Cox regression model summarize decaying vaccine-free population. total 203 subjects 297 analytic samples were period up 588 days. Our suggests that more than four months pertains only 25% titers. GEE indicates longer follow-up was significantly lower titer. indicated disease severity advanced condition maintaining (adjusted hazard ratio: 2.01, 95% CI: 1.11–3.63) smoking also higher risk negative 0.55, 0.33–0.92). Neutralizing diminished year. response naturally provides reference vaccinations.

Language: Английский

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Outpatient COVID-19 convalescent plasma recipient antibody thresholds correlated to reduced hospitalizations within a randomized trial

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: April 19, 2023

ABSTRACT BACKGROUND The COVID-19 convalescent plasma (CCP) viral specific antibody levels that translate into recipient post-transfusion sufficient to prevent disease progression is not defined. METHODS This secondary analysis correlated donor and hospitalization risk among unvaccinated, seronegative CCP recipients within the outpatient, double blind, randomized clinical trial compared control plasma. majority of arm hospitalizations (15/17, 88%) occurred in this subgroup. A functional cutoff delineate high versus low was established by two methods: 1) analyzing virus neutralization-equivalent anti-S-RBD IgG responses donors or 2) receiver operating characteristic (ROC) analysis. RESULTS SARS-CoV-2 diluted a factor 21.3 from matched units. Viral delivered approximated 1.2 mg. transfused early (symptom onset 5 days) had no hospitalizations. for thresholds reduced found significant association with Fisher’s exact test between antibodies all other (or plasma) cutoffs both methods-donor neutralization-based cutoff: (0/85; 0% 15/276; 5.6%) p=0.03 ROC based (0/94; 15/267; 5.4%) p=0.01. CONCLUSION In recipients, transfusion units corresponding upper 30% study outpatient These level units, given early, should be reserved therapeutic use. Trial registration: NCT04373460 FUNDING Defense Health Agency others.

Language: Английский

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Surrogate virus neutralisation test based on nanoluciferase-tagged antigens to quantify inhibitory antibodies against SARS-CoV-2 and characterise Omicron-specific reactivity

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Oct. 10, 2023

ABSTRACT Virus-specific antibodies are important determinants of protective immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While regarded as the gold standard for detecting functional antibodies, conventional virus neutralisation tests (VNT) or pseudotyped (pVNT) require biosafety level 3 facilities. Alternatively, virus-free surrogate test (sVNT) quantifies inhibitory that prevent spike protein from binding to its receptor, human angiotensin-converting enzyme (hACE2). We evaluated secreted nanoluciferase (NLuc)-tagged (S) fragments diagnostic antigens in sVNT framework a vaccination study. First, different lengths were tested their suitability capture immunoassay (EIA) using unprocessed culture supernatants transfected cells, identifying receptor domain (RBD) S optimal construct. The sensitivity in-house relying on NLuc-labelled RBD equalled surpassed commercial ( cPass , GenScript Diagnostics) and an pVNT four weeks after first (98% vs. 94% 72%, respectively), reaching 100% all assays second third vaccinations. Additionally, serum reactivity with constructs Omicron BA.1 was tested. Compared EIA, displayed superior discrimination between wild-type- variant-specific sera. Differences most pronounced vaccinations, whereas resulted robust, cross-reactive detection constructs. In conclusion, utilising permit quantification assessment SARS-CoV-2-specific differences reactivity. Potential applications include monitoring therapy vaccine efficacy follow-up prolonged disease courses high-risk groups. Designed straightforward, highly flexible modular systems, these can be readily adapted further emerging viral variants.

Language: Английский

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Measuring Variant-Specific Neutralizing Antibody Profiles after Bivalent SARS-CoV-2 Vaccinations by a Multivariant Surrogate Virus Neutralization Microarray

Published: Nov. 15, 2023

The capability of antibodies to neutralize different SARS-CoV-2 variants varies among individuals depending on the previous exposure wild-type- or Omicron-specific immunogens by mono- bivalent vaccinations infections. Such profiles neutralizing (nAbs) usually have be assessed laborious live virus-neutralization tests (NTs). We therefore analyzed whether a novel multivariant surrogate virus neutralization test (sVNT) (adapted from commercial microarray) that quantifies antibody-mediated inhibition between receptor angiotensin-converting-enzyme 2 (ACE2) and variant-specific receptor-binding domains (RBDs) can assess activity against wild-type, Delta Omicron BA.1, BA.2 BA.5 (sub-) after booster with Omicron-adapted vaccines in manner similar live-virus NTs. Indeed, using NTs as reference, we found significant correlation NT titers levels ACE2-RBD binding (p < 0.0001, r ≤ 0.78 respectively). Furthermore, sVNTs identified higher values BA.1 vaccinated than those monovalent wild-type vaccines. Our data thus demonstrate ability detect nAbs following

Language: Английский

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Development of automated microfluidic immunoassays for the detection of SARS-CoV-2 antibodies and antigen

Journal of Immunological Methods, Journal Year: 2023, Volume and Issue: 524, P. 113586 - 113586

Published: Nov. 30, 2023

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of disease 2019 (COVID-19) global pandemic. Rapid and sensitive detection virus soon after infection important for treatment prevention transmission COVID-19, antibodies epidemiology, assessment vaccine immunogenicity, identification natural reservoir intermediate host(s). Patient nasal or oropharyngeal swabs saliva used in conjunction with polymerase chain reaction (PCR) detect SARS-CoV-2 RNA, whereas lateral flow immunoassays (LFI) proteins. Enzyme-linked immunosorbent assays (ELISA) anti-SARS-CoV-2 blood. Although effective, these have poor sensitivity (e.g., LFI) are labor intensive time consuming (PCR ELISA). Here we describe development rapid, automated ELISA-based to antigens against virus. The Simple Plex™ platform uses rapid microfluidic kinetics analyte small sample volumes. We developed three <90-min Plex that measure either immune response SARS-CoV-2, including neutralizing antibodies, serum from COVID-19 patients.

Language: Английский

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