Fig. 1: BBV152 induces robust antibody response to SARS-CoV-2 and its variants.
a, Study design to investigate the BBV152-elicited immune memory against SARS-CoV-2 and its variants. b,c, The end-point titre (ET) of SARS-CoV-2-specific antibodies measured by in-house ELISA in plasma samples derived from BBV152 vaccinated individuals (‘BBV152’) and individuals recovered from mild COVID-19 (‘COVID-19’) for spike protein (b) and nucleoprotein (c). d,e, Correlation between anti-spike and anti-nucleoprotein IgG in vaccinated (d) and COVID-19 (e) subjects. f, Comparison of anti-RBD IgG levels measured as AUC in response to ancestral SARS-CoV-2 and its Alpha, Beta, Gamma, Kappa and Delta variants in vaccinated and mild COVID-19-recovered individuals. The fold reduction in IgG levels in variant-RBD with respect to ancestral SARS-CoV-2-RBD is represented at the top of the dataset for each variant. g,h, NT50 estimated using the SARS-CoV-2 pseudovirus (PSV) expressing full-length spike protein of the ancestral virus and its Alpha, Beta and Delta variants in BBV152 (g) (n = 52) and mild COVID-19 (h) (n = 33). The fold reduction in PSV neutralizing antibody titres with respect to ancestral virus is represented at the top of the dataset for each variant. Black bars indicate geometric mean ± s.d. in b and c, and median in f. Dotted lines represent the cut-off for positivity generated using the pre-pandemic samples from healthy donors. Schematic in a was created using Biorender. Statistics by two-tailed Mann-Whitney test (b,c), two-tailed Spearman correlation coefficient (d,e), mixed-effect analysis followed by Tukey’s multiple comparisons (f) and one-way ANOVA followed by Dunn’s multiple comparisons (g,h). NS, non-significant.
