Extended Data Fig. 2: Validation of the 20-plex sVNT with WHO International Standard (IS) SARS-CoV-2 serum panel 20/136.
From: SARS-CoV-2 Omicron variant emerged under immune selection
a, ACE2-RBD binding analysis. 600 beads/RBD were pre-incubated with increased concentration of PE-conjugated ACE2 for 30 min at 37 °C. The Mean Fluorescent Intensity (MFI) were acquired using MagPix Luminex machine. The data presented were from three independent experiments. Error bar indicates standard deviation of mean. b, multiplex sVNT analysis of WHO IS 20/136, with 2-fold serial dilution starting from 1:20. The data presented were from three independent experiments. Error bar indicates standard deviation of mean. c, Calibration of WHO IS unit (IU/ml) using multiplex sVNT on SARS-CoV-2 ancestral strain. Three independent runs were used to perform the correlation of multiplex sVNT inhibition % to IU/ml and logistic regression modelling was performed. The upper and lower 95% confident interval of the mean was plotted in blue shade. The modelled equation for IU/ml to inhibition % and a pseudoR2 (calculated by 1-deviance/null deviance) was marked on the left upper corner. Pearson’s correlation analysis between multiplex sVNT and pVNT on d, ancestral (n = 120) and e, Omicron BA.1 (n = 120). f, Pearson’s correlation analysis between multiplex sVNT and PRNT on Omicron BA.1 (n = 120). Correlation and linear regression analyses were performed in GraphPad Prism 8 using Pearson’s correlation coefficients.
