surrogate neutralization test (svnt, genscript cpass)  (GenScript corporation)

Journal: npj Viruses

Article Title: Survey of white-footed mice ( Peromyscus leucopus ) in Connecticut, USA reveals low SARS-CoV-2 seroprevalence and infection with divergent betacoronaviruses

doi: 10.1038/s44298-023-00010-4

Figure Lengend Snippet: A Map of sampling locations for white-footed mice in Guilford (Mice 1) and North Branford (Mice 2) and white-tailed deer in Norwalk (Deer 1) and Bridgeport (Deer 2) in Connecticut. The pin location corresponds to the mean coordinates for samples for which we had precise geographic locations (Mice 1). For the other groups (Mice 2, Deer 1, and Deer 2), the pin location shows the approximate sampling location. The inset shows the approximate sampling area within Connecticut. B Monthly number of sera and wild-type neutralizing antibody results for white-footed mice in residential and forested settings and deer in two settings at the residential/forest interface. For the 2020–2021 white-footed mice sera, we only pre-screened the last sample in the case of multiple recaptures, and thus these are not included in the total counts. In addition, we only tested 2020–2021 white-footed mouse samples for neutralizing antibodies if they passed the pre-screening ELISA (Supplementary Fig. ). For 2022 white-footed mice and 2021/2022 deer, we forwent the pre-screening ELISA and tested all samples for neutralizing antibodies via the sVNT. We tested the samples either in duplicate initially or in singlicate with a subsequent confirmatory duplicate in the case of an initial positive, unless there was insufficient volume. Note the different y -axes for each plot. * Indicates a second positive for an individual recaptured animal. One deer in July 2021 previously tested positive in June 2021. An additional deer tested positive twice during July 2022.

Article Snippet: We used a surrogate virus neutralization test (sVNT) (Genscript cPass Ref L00847) to detect wild-type SARS-CoV-2 neutralizing antibodies (Fig. ) .

Techniques: Sampling, Enzyme-linked Immunosorbent Assay

Journal: npj Viruses

Article Title: Survey of white-footed mice ( Peromyscus leucopus ) in Connecticut, USA reveals low SARS-CoV-2 seroprevalence and infection with divergent betacoronaviruses

doi: 10.1038/s44298-023-00010-4

Figure Lengend Snippet: Percent signal inhibition for each SARS-CoV-2 variant relative to the kit negative control using the sVNT. We tested each sample in duplicate at 1:10 dilution against wild-type, Alpha (B.1.1.7), and Delta (B.1.617.2). We included wild-type SARS-CoV-2 kit controls, as well as a wild-type neutralizing antibody negative deer. The dashed line indicates the ≥ 30% positivity cutoff. The sample IDs in the legend are in order of descending mean percent inhibition for wild-type SARS-CoV-2. “R” at the end of a sample ID indicates a recaptured animal.

Article Snippet: We used a surrogate virus neutralization test (sVNT) (Genscript cPass Ref L00847) to detect wild-type SARS-CoV-2 neutralizing antibodies (Fig. ) .

Techniques: Inhibition, Variant Assay, Negative Control

Journal: Microbiology Spectrum

Article Title: The Comparability of Anti-Spike SARS-CoV-2 Antibody Tests is Time-Dependent: a Prospective Observational Study

doi: 10.1128/spectrum.01402-21

Figure Lengend Snippet: Study flow chart. Anti-Spike(S)-antibody (Ab) assays: Roche S, Abbott S. Infection with SARS-CoV-2 was ruled out by detection of antibodies against the SARS-CoV-2 nucleocapsid (N) using the Roche N ECLIA. W, weeks; sVNT, surrogate virus neutralization test.

Article Snippet: Binding reactivities (Roche, Abbott) were compared to a well-described CE-IVD marked surrogate virus neutralization test (GenScript cPass sVNT) ( , ).

Techniques: Infection, Virus, Neutralization

Journal: Microbiology Spectrum

Article Title: The Comparability of Anti-Spike SARS-CoV-2 Antibody Tests is Time-Dependent: a Prospective Observational Study

doi: 10.1128/spectrum.01402-21

Figure Lengend Snippet: (A) Antibody levels (Roche, Abbott) and percent inhibition in a surrogate virus neutralization test (sVNT) 3 wk (weeks) after the first dose of AZD1222, prebooster (11w after the first dose), and 3 wk postbooster. Dotted lines indicate the test system threshold for positivity (Roche: 0.8 BAU/mL, Abbott 7.1 BAU/mL, sVNT 30%) and, in the case of Roche, the upper level of quantification (2,500 BAU/mL). Green lines represent the group median. ****, P < 0.0001 in Wilcoxon tests. (B) Longitudinal changes of individual Roche, Abbott, and cPass surrogate virus neutralization test (sVNT) results: 3 wk (3 weeks) after the first dose, before the booster dose, and 3 wk after the booster dose. According to the manufacturers, Roche results ≥15 BAU/mL correlate with a positive neutralization test, Abbott results ≥149,1 BAU/mL correspond to a neutralization titer of at least 1:80; 30% inhibition is considered the sVNTs threshold for positivity. Results are, according to the manufacturer, categorized into low (30 to 60%), medium (60 to 90%), and high (>90%) neutralizing capacity (all levels indicated by dotted lines).

Article Snippet: Binding reactivities (Roche, Abbott) were compared to a well-described CE-IVD marked surrogate virus neutralization test (GenScript cPass sVNT) ( , ).

Techniques: Inhibition, Virus, Neutralization

Journal: Microbiology Spectrum

Article Title: The Comparability of Anti-Spike SARS-CoV-2 Antibody Tests is Time-Dependent: a Prospective Observational Study

doi: 10.1128/spectrum.01402-21

Figure Lengend Snippet: Linear regression lines (±95% confidence intervals) for c-pass surrogate virus neutralization test (sVNT) results and logarithmic binding assay results (top, Abbott; bottom, Roche). The dotted vertical line represents the sVNT threshold for positivity (30% inhibition). According to the manufacturers, Roche results ≥15 BAU/mL correlate with a positive neutralization test, Abbott results ≥149,1 BAU/mL correspond to a neutralization titer of at least 1:80 as indicated by horizontal dotted lines. 3 wk, 3 weeks; BAU/mL, binding antibody units per milliliter.

Article Snippet: Binding reactivities (Roche, Abbott) were compared to a well-described CE-IVD marked surrogate virus neutralization test (GenScript cPass sVNT) ( , ).

Techniques: Virus, Neutralization, Binding Assay, Inhibition

Journal: Microbiology Spectrum

Article Title: The Comparability of Anti-Spike SARS-CoV-2 Antibody Tests is Time-Dependent: a Prospective Observational Study

doi: 10.1128/spectrum.01402-21

Figure Lengend Snippet: Spearman’s ρ of rank correlations between Nil-corrected interferon γ (IFN-γ) levels after incubation with Quantiferon SARS-CoV-2 antigen mixtures 1 (Ag1-Nil) or 2 (Ag2-Nil) and antibody levels ^a

Article Snippet: Binding reactivities (Roche, Abbott) were compared to a well-described CE-IVD marked surrogate virus neutralization test (GenScript cPass sVNT) ( , ).

Techniques: Incubation