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1.
Infect Dis Ther ; 12(1): 177-191, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36376733

ABSTRACT

INTRODUCTION: There is a need for automated, high-throughput assays to quantify immune response after SARS-CoV-2 vaccination. This study assessed the combined utility of the Elecsys® Anti-SARS-CoV-2 S (ACOV2S) and the Elecsys Anti-SARS-CoV-2 (ACOV2N) assays using samples from the mRNA-1273 (Spikevax™) phase 2 trial (NCT04405076). METHODS: Samples from 593 healthy participants in two age cohorts (18-54 and ≥ 55 years), who received two injections with placebo (n = 198) or mRNA-1273 (50 µg [n = 197] or 100 µg [n = 198]), were collected at days 1 (first vaccination), 15, 29 (second vaccination), 43, and 57. ACOV2S results were used to assess humoral response to vaccination in different subgroups and were compared to live virus microneutralization assay. Samples from patients with either previous or concomitant infection (identified per ACOV2N) were analyzed separately. RESULTS: Receptor-binding domain-specific antibodies were readily detectable by ACOV2S for the vast majority of participants (174/189, 92.1% [50 µg dose] and 178/192, 92.7% [100 µg dose]) at the first post-vaccination assessment, with non-converters predominantly older in age. Seroconversion for all participants was observed at day 29 (before the second vaccine dose). Two weeks after the first dose, geometric mean concentration (GMC) of antibody levels was 1.37-fold higher in the 100 versus 50 µg group (p = 0.0098), reducing to 1.09-fold 2 weeks after the second dose (p = 0.0539, n.s.). In both dose groups, a more pronounced response was observed in the younger versus older age group on day 15 (50 µg, 2.49-fold [p < 0.0001]; 100 µg, 3.94-fold [p < 0.0001] higher GMC, respectively), and day 29 (1.93-fold, p = 0.0002, and 2.44-fold, p < 0.0001). Eight subjects had previous or concomitant SARS-CoV-2 infection; vaccination boosted their humoral response to very high ACOV2S results compared to infection-naïve recipients. ACOV2S strongly correlated with microneutralization (Pearson's r = 0.779; p < 0.0001), including good qualitative agreement. CONCLUSION: These results confirmed that ACOV2S is a highly valuable assay for tracking vaccine-related immune responses. Combined application with ACOV2N enables monitoring for breakthrough infection or stratification of previous natively infected individuals. The adaptive measuring range and high resolution of ACOV2S allow for early identification of seroconversion and resolution of very high titers and longitudinal differences between subgroups. Additionally, good correlation with live virus microneutralization suggests that ACOV2S is a reliable estimate of neutralization capacity in routine diagnostic settings.

2.
medRxiv ; 2021 Oct 19.
Article in English | MEDLINE | ID: mdl-34642699

ABSTRACT

BACKGROUND: The ability to quantify an immune response after vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential. This study assessed the clinical utility of the quantitative Roche Elecsys® Anti-SARS-CoV-2 S assay (ACOV2S) using samples from the 2019-nCoV vaccine (mRNA-1273) phase 1 trial (NCT04283461). METHODS: Samples from 30 healthy participants, aged 18-55 years, who received two injections with mRNA-1273 at a dose of 25 µg (n=15) or 100 µg (n=15), were collected at Days 1 (first vaccination), 15, 29 (second vaccination), 43 and 57. ACOV2S results (shown in U/mL - equivalent to BAU/mL per the first WHO international standard) were compared with results from ELISAs specific to antibodies against the Spike protein (S-2P) and the receptor binding domain (RBD) as well as neutralization tests including nanoluciferase (nLUC80), live-virus (PRNT80), and a pseudovirus neutralizing antibody assay (PsVNA50). RESULTS: RBD-specific antibodies were already detectable by ACOV2S at the first time point of assessment (d15 after first vaccination), with seroconversion before in all but 2 participants (25 µg dose group); all had seroconverted by Day 29. Across all post-baseline visits, geometric mean concentration of antibody levels were 3.27-7.48-fold higher in the 100 µg compared with the 25 µg dose group. ACOV2S measurements were highly correlated with those from RBD ELISA (Pearson's r=0.938; p<0.0001) and S-2P ELISA (r=0.918; p<0.0001). For both ELISAs, heterogeneous baseline results and smaller increases in antibody levels following the second vs first vaccination compared with ACOV2S were observed. ACOV2S showed absence of any baseline noise indicating high specificity detecting vaccine-induced antibody response. Moderate-strong correlations were observed between ACOV2S and neutralization tests (nLUC80 r=0.933; PsVNA50, r=0.771; PRNT80, r=0.672; all p≤0.0001). CONCLUSION: The Elecsys Anti-SARS-CoV-2 S assay (ACOV2S) can be regarded as a highly valuable method to assess and quantify the presence of RBD-directed antibodies against SARS-CoV-2 following vaccination, and may indicate the presence of neutralizing antibodies. As a fully automated and standardized method, ACOV2S could qualify as the method of choice for consistent quantification of vaccine-induced humoral response.

3.
Front Immunol ; 12: 798117, 2021.
Article in English | MEDLINE | ID: mdl-35126362

ABSTRACT

Background: The ability to quantify an immune response after vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential. This study assessed the clinical utility of the quantitative Roche Elecsys® Anti-SARS-CoV-2 S assay (ACOV2S) using samples from the 2019-nCoV vaccine (mRNA-1273) phase 1 trial (NCT04283461). Methods: Samples from 30 healthy participants, aged 18-55 years, who received two injections with mRNA-1273 at a dose of 25 µg (n=15) or 100 µg (n=15), were collected at Days 1 (first vaccination), 15, 29 (second vaccination), 43 and 57. ACOV2S results (shown in U/mL - equivalent to BAU/mL per the first WHO international standard) were compared with results from ELISAs specific to antibodies against the Spike protein (S-2P) and the receptor binding domain (RBD) as well as neutralization tests including nanoluciferase (nLUC80), live-virus (PRNT80), and a pseudovirus neutralizing antibody assay (PsVNA50). Results: RBD-specific antibodies were already detectable by ACOV2S at the first time point of assessment (d15 after first vaccination), with seroconversion before in all but two participants (25 µg dose group); all had seroconverted by Day 29. Across all post-baseline visits, geometric mean concentration of antibody levels was 3.27-7.48-fold higher in the 100 µg compared with the 25 µg dose group. ACOV2S measurements were highly correlated with those from RBD ELISA (Pearson's r=0.938; p<0.0001) and S-2P ELISA (r=0.918; p<0.0001). For both ELISAs, heterogeneous baseline results and smaller increases in antibody levels following the second vs first vaccination compared with ACOV2S were observed. ACOV2S showed absence of any baseline noise indicating high specificity detecting vaccine-induced antibody response. Moderate-strong correlations were observed between ACOV2S and neutralization tests (nLUC80 r=0.933; PsVNA50, r=0.771; PRNT80, r=0.672; all p ≤ 0.0001). Conclusion: The Elecsys Anti-SARS-CoV-2 S assay (ACOV2S) can be regarded as a highly valuable method to assess and quantify the presence of RBD-directed antibodies against SARS-CoV-2 following vaccination and may indicate the presence of neutralizing antibodies. As a fully automated and standardized method, ACOV2S could qualify as the method of choice for consistent quantification of vaccine-induced humoral response.


Subject(s)
2019-nCoV Vaccine mRNA-1273/immunology , COVID-19/diagnosis , Enzyme-Linked Immunosorbent Assay/methods , SARS-CoV-2/physiology , Adolescent , Adult , Aged , Automation , COVID-19/immunology , Female , Humans , Immunity, Humoral , Immunogenicity, Vaccine , Male , Middle Aged , Neutralization Tests , Reference Standards , Young Adult
4.
Rheumatology (Oxford) ; 52(7): 1245-53, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23459699

ABSTRACT

OBJECTIVES: To investigate the frequency of anti-infliximab antibodies in patients with RA and the associations with adverse drug reactions and treatment failure. METHODS: Based on the DANBIO registry, patients with RA who initiated treatment with infliximab at Hvidovre Hospital between 2000 and 2008 and had available serum samples were identified. The patients were followed for 52 weeks. Anti-infliximab antibodies were determined prior to infusion at baseline and during follow-up (weeks 2, 6, 14 and 52 or at withdrawal) using the IMPACT indirect assay (Roche Diagnostics) and merged with clinical data prospectively registered in the DANBIO registry. RESULTS: A total of 218 patients with RA were included (80% females, median age 56 years, disease duration 10 years, 65% RF positive, median DAS28 = 5.0). During the 52-week follow-up, 28 patients (13%) withdrew due to adverse events and 50 (23%) due to treatment failure. Antibodies were detected in 118 patients (54%) during follow-up. Patients with detectable anti-infliximab antibodies after 6 weeks had an increased risk of adverse drug reactions [hazard ratio (HR) = 5.06, 95% CI 2.36, 10.84; P < 0.0001] compared with patients without anti-infliximab antibodies. Similar results were observed in patients with anti-infliximab antibodies after 14 weeks (HR = 3.30, 95% CI 1.56, 6.99; P = 0.0009). Patients with detectable anti-infliximab antibodies during the 52-week follow-up were less likely to achieve sustained minimal disease activity and remission. CONCLUSION: Early anti-infliximab antibody formation increased the risk of adverse drug reactions, including infusion reactions. Anti-infliximab antibody formation during the 52-week follow-up decreased the likelihood of minimal disease activity and remission in patients with RA treated in routine care.


Subject(s)
Antibodies, Anti-Idiotypic/blood , Antibodies, Monoclonal/immunology , Antirheumatic Agents/immunology , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/immunology , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal/therapeutic use , Antirheumatic Agents/adverse effects , Antirheumatic Agents/therapeutic use , Female , Follow-Up Studies , Humans , Infliximab , Male , Middle Aged , Radioimmunoassay , Registries , Risk Factors , Treatment Failure , Treatment Refusal , Young Adult
5.
Biom J ; 51(4): 610-26, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19688757

ABSTRACT

To classify patients either as resistant or non-resistant to HIV therapy based on longitudinal viral load profiles, we applied longitudinal quadratic discriminant analysis and examined various measures, mainly derived from the Brier Score, to assess the biomarker performance in terms of discrimination and calibration. The analysis of the application data revealed an increase in performance by using longer profiles instead of single biomarker measurements. Simulations showed that the selection of mixed models for the estimation of the group-specific discriminant rule parameters should be based on BIC, rather than on the best performance measure. An incorrect model selection can lead to spuriously better or worse performance as misclassification and classification certainty regards, especially with increasing length of the profiles and for more complex models with random slopes.


Subject(s)
Anti-HIV Agents/therapeutic use , Biomarkers/blood , Drug Resistance, Viral , HIV Infections/blood , HIV Infections/drug therapy , Longitudinal Studies , Outcome Assessment, Health Care/methods , Discriminant Analysis , HIV Infections/epidemiology , Humans , Reproducibility of Results , Sensitivity and Specificity , Treatment Outcome
6.
Biomarkers ; 13(1): 88-105, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18188726

ABSTRACT

OBJECTIVE: To test if a combination of biomarkers can increase the classification power of autoantibodies to cyclic citrullinated peptides (anti-CCP) in the diagnosis of rheumatoid arthritis (RA) depending on the diagnostic situation. METHODS: Biomarkers were subject to three inclusion/exclusion criteria (discrimination between RA patients and healthy blood donors, ability to identify anti-CCP-negative RA patients, specificity in a panel with major non-rheumatological diseases) before univariate ranking and multivariate analysis was carried out using a modelling panel (n = 906). To enable the evaluation of the classification power in different diagnostic settings the disease controls (n = 542) were weighted according to the admission rates in rheumatology clinics modelling a clinic panel or according to the relative prevalences of musculoskeletal disorders in the general population seen by general practitioners modelling a GP panel. RESULT: Out of 131 biomarkers considered originally, we evaluated 32 biomarkers in this study, of which only seven passed the three inclusion/exclusion criteria and were combined by multivariate analysis using four different mathematical models. In the modelled clinic panel, anti-CCP was the lead marker with a sensitivity of 75.8% and a specificity of 94.0%. Due to the lack in specificity of the markers other than anti-CCP in this diagnostic setting, any gain in sensitivity by any marker combination is off-set by a corresponding loss in specificity. In the modelled GP panel, the best marker combination of anti-CCP and interleukin (IL)-6 resulted in a sensitivity gain of 7.6% (85.9% vs. 78.3%) at a minor loss in specificity of 1.6% (90.3% vs. 91.9%) compared with anti-CCP as the best single marker. CONCLUSION: Depending on the composition of the sample panel, anti-CCP alone or anti-CCP in combination with IL-6 has the highest classification power for the diagnosis of established RA.


Subject(s)
Antibodies, Antinuclear/analysis , Arthritis, Rheumatoid/diagnosis , Biomarkers/analysis , Peptides, Cyclic/immunology , Citrulline/immunology , Female , Humans , Longitudinal Studies , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Sensitivity and Specificity , Serum Amyloid A Protein/analysis
7.
J Dtsch Dermatol Ges ; 1(7): 547-57, 2003 Jul.
Article in German | MEDLINE | ID: mdl-16295040

ABSTRACT

BACKGROUND: Irritant contact dermatitis of the hands is very common in dental laboratory technicians due to frequent contact with various irritants. Barrier creams (HS) are often avoided because a tight grip of tools and small objects is necessary; furthermore dental objects must not be contaminated by HS. In this study the efficacy of HS applied during working hours was compared to skin care products (HP) applied only after work. METHOD: 2 popular commercial HS (HS-1, HS-2) and 2 moisturizers containing urea and beeswax respectively (HP-1, HP-2) were evaluated in 5 laboratories by a total of 192 technicians. Every technician used one HS (several applications during working hours) and one HP applied at home at least once daily for 4 weeks each with a wash-out period of 2 weeks in between. The sequence HS-HP, HP-HS was randomized for every laboratory in two single blind cross over designs for both combinations (HS-1 with HP-1, HS-2 with HP-2). The technicians scored the products on a scale of efficacy (worse, none, good, very good). The skin condition was evaluated by a dermatologist at the beginning of the study, after 4, 6 and 10 weeks on a scale for erythema, infiltration, vesicles, fissures and scaling to produce a sum score. Furthermore, transepidermal water loss (TEWL) was measured on the back of the hand and on the ventral aspect of the forearm at the beginnung and the end of the 4 weeks application period. The quotient of these two parameters was used for statistical evaluation (covariance analysis). RESULTS: The assessment of either "good" or "very good" was as follows: HS-1 58%; HS-2 67%; HP-1 77%; HP-2 98%. Both HP, particularly HP-2, were judged superior to either HS. This was confirmed by the improvement of the skin condition (HS-1 35%; HS-2 44%; HP-1 55%; HP-2 56%). Statistical significance of the differences in TEWL data was clearly demonstrated: HP-1 better than HS-1 (p = 0.007); HP-2 better than HS-2 (p = 0.03). The acceptance of the products was high. The majority was willing to continue its usage after the study (68 %-89 %). CONCLUSIONS: The results demonstrate that the use of after work moisturizers is highly beneficial and under the chosen study conditions even superior to barrier creams applied at work. This approach is more practical for many professions and may effectively reduce the frequency of irritant contact dermatitis.


Subject(s)
Benzenesulfonates/administration & dosage , Dental Technicians , Dermatitis, Irritant/prevention & control , Dermatitis, Occupational/prevention & control , Laboratories, Dental , Lanolin/administration & dosage , Protective Agents/administration & dosage , Skin Cream/administration & dosage , Stearates/administration & dosage , Adolescent , Adult , Drug Administration Schedule , Drug Combinations , Female , Humans , Male , Middle Aged , Self Care , Young Adult
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