Fig. 1

a MenA- and MenC-specific serum bactericidal assay titres at each study time point, with geometric mean titre (dot) and 95% confidence intervals (bars) across all groups indicated and group allocation denoted by colour. b MenA-, MenC- and diphtheria toxoid-specific cultured antibody-secreting cell (ASC) ELISpots at each study time point, with geometric mean concentrations (dot) and 95% confidence intervals (bars) across all groups indicated and group allocation denoted by colour. Group 1 (G1), MenACWY-CRM (day 0) + MenACWY-CRM (day 28); group 2 (G2), intramuscular MenACWY-PS (day 0) + MenACWY-CRM (day 28); group 3 (G3), subcutaneous MenACWY-PS (day 0) + MenACWY-CRM (day 28); group 4 (G4), one-fifth dose intramuscular MenACWY-PS (day 0) + MenACWY-CRM (day 28). c MenA-, MenC- and diphtheria toxoid-specific ex vivo antibody-secreting cell (ASC) ELISpots, 7 days after each dose of vaccine (day 7 and day 35). ***p <0.001, **p < 0.01, *p < 0.05 by Welch’s t-test, comparing protein-conjugated vaccine (G1) with plain-polysaccharide vaccine (G2, G3 and G4) recipients, or paired t-test between time points (denoted by horizontal lines)