Journal: Vaccine

Article Title: Humoral immune response characterization of heterologous prime-boost vaccination with CoronaVac and BNT162b2

doi: 10.1016/j.vaccine.2022.07.023

Figure Lengend Snippet: Fc-mediated functions and RBD-ACE2 binding inhibition of specific serum anti-RBD immunoglobulins . Figure shows ADCC (A) and ADCP (B) Fc-mediated functions of serum anti-RBD immunoglobulin in 20 individuals early after two doses of Coronavac (t 1 ) and after heterologous booster with BNT162b2 (t 3 ). Endpoint titers were calculated by interpolating the reciprocal of serum dilutions to baseline, whose values were determined for each plate as the mean signal in absence of serum plus three standard deviations. Inhibition of RBD-ACE2 binding (C) and serum anti-RBD IgG levels (D) were measured in the same samples, showing a similar behavior over time. Comparison of the RBD-ACE2 binding inhibition activity against SARS-CoV-2 Wuhan and Omicron variants were carried out by sVNT in these 20 samples (E). Numbers represents median values and the interquartile range (in parentheses). Comparisons between groups were carried out using Wilcoxon test. *p < 0.05, ** p = 0.01–0.001, *** p < 0.001. BAU, binding antibody units; AU, arbitrary units.

Article Snippet: The blockade of RBD-ACE2 interaction by specific anti-SARS-CoV-2 antibodies was analyzed by using an in vitro surrogate virus neutralization test (sVNT; cPassTM SARS-CoV-2 Neutralization Antibody Detection Kit, GenScript®) in serum from individuals who received heterologous vaccination at t 1 and t 2 (post-2D with CoronaVac) and at t 3 and t 4 (post-3D with BNT162b2), according to manufacturer’s instructions.

Techniques: Binding Assay, Inhibition, Comparison, Activity Assay

Journal: Analytical and Bioanalytical Chemistry

Article Title: Liposome-based high-throughput and point-of-care assays toward the quick, simple, and sensitive detection of neutralizing antibodies against SARS-CoV-2 in patient sera

doi: 10.1007/s00216-023-04548-3

Figure Lengend Snippet: Schematic of the developed high-throughput (i) and point-of care (ii) formats for the detection of neutralizing antibodies directed against the receptor binding domain of SARS-CoV-2. RBD-conjugated liposomes are incubated with patient serum and subsequently (i) immobilized in an ACE2-coated microplate or (ii) mixed with ACE2-biotin and added to a nitrocellulose membrane with streptavidin test line. In presence of neutralizing antibodies, no liposome-binding takes place, and no signals are observed in either format. In the absence of neutralizing antibodies liposomes are (i) bound in the microplate, enabling detection of the released sulforhodamine B via fluorescence after washing and lysis or (ii) bound by the test line, enabling a colorimetric detection via camera or naked eye

Article Snippet: Different competitive ELISAs relying on horseradish peroxidase (HRP)-conjugated RBD or ACE2 for detection are commercially available, such as the cPass™ SARS-CoV-2 Neutralization Antibody Detection Kit from GenScript®, the SARS-CoV-2 sVNT Kit from ProteoGenix, and the iFlash-2019-nCoV Neutralization Antibody Test from YHLO.

Techniques: High Throughput Screening Assay, Binding Assay, Incubation, Fluorescence, Lysis

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Estimating the Neutralizing Effect and Titer Correlation of Semi-Quantitative Anti-SARS-CoV-2 Antibody Immunoassays

doi: 10.3389/fcimb.2022.822599

Figure Lengend Snippet: Analytical performance of each kit in discriminating SARS-CoV-2 infection.

Article Snippet: According to the new cut-offs, the Abbott SARS-CoV-2 IgG II Quant kit demonstrated the highest agreement in predicting high titers of neutralizing antibodies, followed by the GenScript cPass sVNT and Roche Elecsys Anti-SARS-CoV-2 S kits.

Techniques: Infection

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Estimating the Neutralizing Effect and Titer Correlation of Semi-Quantitative Anti-SARS-CoV-2 Antibody Immunoassays

doi: 10.3389/fcimb.2022.822599

Figure Lengend Snippet: Analytical performance for representativeness of neutralizing activity using the pre-defined cut-off values of each immunoassay kit.

Article Snippet: According to the new cut-offs, the Abbott SARS-CoV-2 IgG II Quant kit demonstrated the highest agreement in predicting high titers of neutralizing antibodies, followed by the GenScript cPass sVNT and Roche Elecsys Anti-SARS-CoV-2 S kits.

Techniques: Activity Assay

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Estimating the Neutralizing Effect and Titer Correlation of Semi-Quantitative Anti-SARS-CoV-2 Antibody Immunoassays

doi: 10.3389/fcimb.2022.822599

Figure Lengend Snippet: Titer correlation of the analytical performance of the prediction of neutralizing activity using newly calculated cut-off values determined using Youden’s index.

Article Snippet: According to the new cut-offs, the Abbott SARS-CoV-2 IgG II Quant kit demonstrated the highest agreement in predicting high titers of neutralizing antibodies, followed by the GenScript cPass sVNT and Roche Elecsys Anti-SARS-CoV-2 S kits.

Techniques: Activity Assay

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Estimating the Neutralizing Effect and Titer Correlation of Semi-Quantitative Anti-SARS-CoV-2 Antibody Immunoassays

doi: 10.3389/fcimb.2022.822599

Figure Lengend Snippet: Serial kinetics of antibody titers measured with each method: (A) PRNT ND50, (B.) GenScript cPass sVNT, (C) Roche Elecsys Anti-SARS-CoV-2, (D) Roche Elecsys Anti-SARS-CoV2 S, and (E) Abbott AdviseDx SARS-CoV2 IgG II.

Article Snippet: According to the new cut-offs, the Abbott SARS-CoV-2 IgG II Quant kit demonstrated the highest agreement in predicting high titers of neutralizing antibodies, followed by the GenScript cPass sVNT and Roche Elecsys Anti-SARS-CoV-2 S kits.

Techniques:

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Estimating the Neutralizing Effect and Titer Correlation of Semi-Quantitative Anti-SARS-CoV-2 Antibody Immunoassays

doi: 10.3389/fcimb.2022.822599

Figure Lengend Snippet: Antibody titers by timeline.

Article Snippet: According to the new cut-offs, the Abbott SARS-CoV-2 IgG II Quant kit demonstrated the highest agreement in predicting high titers of neutralizing antibodies, followed by the GenScript cPass sVNT and Roche Elecsys Anti-SARS-CoV-2 S kits.

Techniques:

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Estimating the Neutralizing Effect and Titer Correlation of Semi-Quantitative Anti-SARS-CoV-2 Antibody Immunoassays

doi: 10.3389/fcimb.2022.822599

Figure Lengend Snippet: Scatter plot and Pearson’s correlation for each method grouped with acute/convalescent phase. (A) GenScript cPass sVNT, (B) Roche Elecsys Anti-SARS-CoV-2, (C) Roche Elecsys Anti-SARS-CoV2 S, and (D) Abbott AdviseDx SARS-CoV2 IgG II were compared with PRNT, respectively. Each colored line depicts the linear regression model and the surrounding grey-colored area represents the 95% confidence interval.

Article Snippet: According to the new cut-offs, the Abbott SARS-CoV-2 IgG II Quant kit demonstrated the highest agreement in predicting high titers of neutralizing antibodies, followed by the GenScript cPass sVNT and Roche Elecsys Anti-SARS-CoV-2 S kits.

Techniques: