Journal: The Journal of Clinical Investigation

Article Title: Prevalence and functional profile of SARS-CoV-2 T cells in asymptomatic Kenyan adults

doi: 10.1172/JCI170011

Figure Lengend Snippet: ( A ) Individuals with no history of COVID-19 symptoms (including cough, shortness of breath, fever, or sinus congestion) and no contact with confirmed SARS-CoV-2–infected individuals were recruited in 2 counties of Kenya highlighted in purple and green. Elgeyo Marakwet ( n = 40 participants); Kisumu ( n = 40 participants). ( B ) Sera from participants were analyzed with 3 antibody tests measuring spike-specific antibodies: cPass measuring SARS-CoV-2–neutralizing antibodies with a surrogate virus neutralization test (sVNT); InBios SCoV-2 Detect IgG ELISA as an initial test followed by the EUROIMMUN anti–SARS-CoV-2 test as a confirmatory test for participants who were positive by InBios; and 1 antibody test, EUROIMMUN-NCP, measuring NP-specific antibodies. The percentages of participants positive for the different tests are shown in red. ( C ) Antibody data are shown for the individual participants from Elgeyo Marakwet and Kisumu. All participants were tested with the cPass sVNT against the spike protein of the first SARS-CoV-2 variant (Wuhan-Hu-1 strain) and the spike protein of the SARS-CoV-2 variants Delta and Omicron. In addition, test results from the InBios/EUROIMMUN and EUROIMMUN-NCP tests are shown (+, positive; –, negative; ±, borderline).

Article Snippet: SARS-CoV-2–neutralizing antibodies were analyzed using a surrogate neutralization assay (cPass, GenScript Biotech) that measures how neutralizing antibodies in the serum bind to the HRP-labeled SARS-CoV-2 RBD and prevent it from binding to the hACE2 protein ( ).

Techniques: Infection, Virus, Neutralization, Enzyme-linked Immunosorbent Assay, Variant Assay

Journal: International Journal of Obesity (2005)

Article Title: The majority of SARS-CoV-2-specific antibodies in COVID-19 patients with obesity are autoimmune and not neutralizing

doi: 10.1038/s41366-021-01016-9

Figure Lengend Snippet: Bars show means ± SE (standard errors) of SARS-CoV-2 Spike-specific IgG antibodies (OD) measured by ELISA. Mean comparisons between groups were performed by one-way ANOVA ( F = 23.76, p = 0.0029). * p < 0.05, *** p < 0.001, **** p < 0.0001.

Article Snippet: Neutralizing antibodies were measured by the cPass neutralization ELISA assay, a surrogate plaque reducing neutralization test (sVNT) using the DYNEX Agility® Automated ELISA system.

Techniques: Enzyme-linked Immunosorbent Assay

Journal: International Journal of Obesity (2005)

Article Title: The majority of SARS-CoV-2-specific antibodies in COVID-19 patients with obesity are autoimmune and not neutralizing

doi: 10.1038/s41366-021-01016-9

Figure Lengend Snippet: Neutralizing antibodies were measured by the cPass neutralization ELISA assay, a surrogate plaque reducing neutralization test (sVNT) using the DYNEX Agility® Automated ELISA system. This test allows the identification of neutralizing antibodies with high, medium, or low neutralization potential, corresponding to >5000, 1500–500, and <1500 U/mL, respectively. Bars show means ± SE (standard errors) of Spike-specific neutralizing IgG antibodies (U/mL). Mean comparisons between groups were performed by unpaired Student’s t test. **** p < 0.0001.

Article Snippet: Neutralizing antibodies were measured by the cPass neutralization ELISA assay, a surrogate plaque reducing neutralization test (sVNT) using the DYNEX Agility® Automated ELISA system.

Techniques: Neutralization, Enzyme-linked Immunosorbent Assay

Journal: International Journal of Obesity (2005)

Article Title: The majority of SARS-CoV-2-specific antibodies in COVID-19 patients with obesity are autoimmune and not neutralizing

doi: 10.1038/s41366-021-01016-9

Figure Lengend Snippet: Bars show means ± SE (standard errors) of anti-MDA ( A ) and anti-AD ( B ) IgG antibodies measured by ELISA. Mean comparisons between groups were performed by one-way ANOVA. A ( F = 82.90, p < 0.0001). B ( F = 32.41, p = 0.049). * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Article Snippet: Neutralizing antibodies were measured by the cPass neutralization ELISA assay, a surrogate plaque reducing neutralization test (sVNT) using the DYNEX Agility® Automated ELISA system.

Techniques: Enzyme-linked Immunosorbent Assay

Journal: International Journal of Obesity (2005)

Article Title: The majority of SARS-CoV-2-specific antibodies in COVID-19 patients with obesity are autoimmune and not neutralizing

doi: 10.1038/s41366-021-01016-9

Figure Lengend Snippet: Bars show means ± SE (standard errors) of CRP serum levels measured by ELISA. Mean comparisons between groups were performed by unpaired Student’s t test. *** p < 0.001.

Article Snippet: Neutralizing antibodies were measured by the cPass neutralization ELISA assay, a surrogate plaque reducing neutralization test (sVNT) using the DYNEX Agility® Automated ELISA system.

Techniques: Enzyme-linked Immunosorbent Assay

Journal: Open Forum Infectious Diseases

Article Title: Evaluation of a Commercial Culture-Free Neutralization Antibody Detection Kit for Severe Acute Respiratory Syndrome-Related Coronavirus-2 and Comparison With an Antireceptor-Binding Domain Enzyme-Linked Immunosorbent Assay

doi: 10.1093/ofid/ofab220

Figure Lengend Snippet: Effect of serial dilution on the accuracy for detecting sera with positive plaque-reduction neutralization test (PRNT)-90 titers. Serial dilution of 16 of the primary specimens with wild-type (WT) PRNT-50 titers ≥1:20 was performed to establish a dilution that increased specificity for detecting those with WT PRNT-90 titers ≥1:20. Three of the 19 specimens with WT PRNT-50 titers ≥1:20—all [PRNT-50 1:20 (+)/PRNT-90 1:20 (−)]—were not available in sufficient quantity to perform serial dilution testing. (A) shows individual data points according to dilution and WT PRNT-90 status (positive ≥1:20). Box plots depict the median and interquartile range. The horizontal dashed line depicts the manufacturer’s recommended cutoff for cPass positivity. (B) details results and estimates of sensitivity and specificity for serial dilution factor. All dilution factors are additional to the 10× dilution required in the manufacturer’s instructions. WT PRNT-90 denotes neutralization titers required for a 90% plaque reduction using severe acute respiratory syndrome-related coronavirus 2 viral culture. FP, false positive; FN, false negative; TN, true negative; TP true positive.

Article Snippet: shows the estimated diagnostic accuracy of the GenScript cPass neutralization antibody detection assay among well characterized specimen panels, according to different reference standards.

Techniques: Serial Dilution, Plaque Reduction Neutralization Test, Neutralization

Journal: Open Forum Infectious Diseases

Article Title: Evaluation of a Commercial Culture-Free Neutralization Antibody Detection Kit for Severe Acute Respiratory Syndrome-Related Coronavirus-2 and Comparison With an Antireceptor-Binding Domain Enzyme-Linked Immunosorbent Assay

doi: 10.1093/ofid/ofab220

Figure Lengend Snippet: Correlation of the GenScript cPass assay with antibodies against receptor binding domain of severe acute respiratory syndrome-related coronavirus 2 (anti-S-RBD) enzyme-linked immunosorbent assay (ELISA) and PLV ID 50 . Correlation of the GenScript cPass assay with the anti-S-RBD ELISA normalized relative luciferase units (RLU) for each plasma tested at a dilution (1:500) is presented. Scatterplots and Pearson correlation coefficient for results obtained with cPass compared with those obtained using laboratory-developed ELISA detecting anti-RBD immunoglobulin (Ig)G, IgM, IgA and to the reciprocal titer of PLV ID 50 (A, B, C, and D, respectively). The vertical dashed line depicts the manufacturer’s recommended cutoff for cPass positivity. Cutoffs for anti-S-RBD ELISA positivity were as follows:; 4.335 for IgG, 2.983 for IgM, and 1.084 for IgA. Cutoff for the reciprocal titer of PLV ID 50 was 50. Specimens from the NML panel 2 and Héma-Québec convalescent plasma donors panel are included in the above figure. Specimens from the NML panel no. 1 were excluded because anti-S-RBD ELISA for IgM and IgA were not performed.

Article Snippet: shows the estimated diagnostic accuracy of the GenScript cPass neutralization antibody detection assay among well characterized specimen panels, according to different reference standards.

Techniques: Binding Assay, Enzyme-linked Immunosorbent Assay, Luciferase, Clinical Proteomics

Journal: Open Forum Infectious Diseases

Article Title: Evaluation of a Commercial Culture-Free Neutralization Antibody Detection Kit for Severe Acute Respiratory Syndrome-Related Coronavirus-2 and Comparison With an Antireceptor-Binding Domain Enzyme-Linked Immunosorbent Assay

doi: 10.1093/ofid/ofab220

Figure Lengend Snippet: Change of signal over time for GenScript cPass and antibodies against receptor binding domain of severe acute respiratory syndrome-related coronavirus 2 ([SARS-CoV-2] anti-RBD) enzyme-linked immunosorbent assay (ELISA). Spaghetti plot of results obtained with cPass (A), and the plots shown in B, C, and D represent (B and C) the areas under the curve (AUC) calculated from relative luciferase units (RLU) obtained with serial plasma dilutions or (D) the normalized RLU for 1 plasma dilution (1:500) for laboratory-developed ELISA detecting anti-RBD immunoglobulin (Ig)G, IgM, and IgA (B, C, D, respectively) among specimens collected at a known interval from SARS-CoV-2 diagnosis. Horizontal lines indicate paired specimens form the same individual. P values are calculated via the Wilcoxon signed-rank test, and values <.05 are designated with an asterisk. In all panels, red dots denote specimens with positive cPass results, and blue dots denote specimens with negative cPass results. cPass positivity based on a cutoff of ≥30% inhibition. Cutoffs for anti-S-RBD ELISA positivity were as follows: 4.335 for IgG, 2.983 for IgM, and 1.084 for IgA.

Article Snippet: shows the estimated diagnostic accuracy of the GenScript cPass neutralization antibody detection assay among well characterized specimen panels, according to different reference standards.

Techniques: Binding Assay, Enzyme-linked Immunosorbent Assay, Luciferase, Clinical Proteomics, Biomarker Discovery, Inhibition

Journal: Journal of Korean Medical Science

Article Title: Comparison of Serologic Response of Hospitalized COVID-19 Patients Using 8 Immunoassays

doi: 10.3346/jkms.2021.36.e64

Figure Lengend Snippet: Clinical sensitivities and specificities of SARS-CoV-2 antibody detection by immunoassay kits

Article Snippet: , GenScript cPass neutralization Ab , 23/24 (0.958, 0.798–0.993) , 48/53 (0.906, 0.797–0.959).

Techniques: Enzyme-linked Immunosorbent Assay, Neutralization

Journal: Journal of Korean Medical Science

Article Title: Comparison of Serologic Response of Hospitalized COVID-19 Patients Using 8 Immunoassays

doi: 10.3346/jkms.2021.36.e64

Figure Lengend Snippet: Comparison of SARS-CoV-2 antibody results by immunoassays in serial 40 samples from 15 confirmed COVID-19 patients

Article Snippet: , GenScript cPass neutralization Ab , 23/24 (0.958, 0.798–0.993) , 48/53 (0.906, 0.797–0.959).

Techniques: Enzyme-linked Immunosorbent Assay, Neutralization