Fig. 1: Antibody response kinetics of one dose Ad26.COV2 (108 or 1010 vp) and two doses BNT162b2 (5 μg/each) vaccines in Syrian hamsters.
Four-to-five-week-old male Syrian hamsters were immunized with one 108 or 1010 vp dose of the Ad26.COV2.S vaccine (n = 49 and 50, respectively), two 5 μg doses of the BNT162b2 vaccine (n = 50), or sham-vaccinated (PBS; n = 59) and followed through 252 days post-vaccination (dpv). a Experimental design, showing the immunizations and blood collections. b–d Serum neutralizing antibody responses through 252 dpv after (b) 1010 vp of Ad26.COV2.S, (c) 108 vp of Ad26.COV2.S, or (d) two 5 μg doses of BNT162b2 as determined by plaque reduction neutralization tests (PRNT) based on a 50% or greater reduction in plaque counts (PRNT50) against the USA_WA1/2020 strain (n = 20/per group). e–g Serum binding antibody responses through 252 dpv after (h) 1010 vp of Ad26.COV2.S, (i) 108 vp of Ad26.COV2.S, or (j) two 5 µg doses of BNT162b2 as determined by optical density at 490 nm (OD490 nm) in an ELISA measuring anti-S1 (USA_WA1/2020) IgG (n = 20/per group). h–j Serum binding antibody responses through 252 dpv after (e) 1010 vp of Ad26.COV2.S, (f) 108 vp of Ad26.COV2.S, or (g) two 5 µg doses of BNT162b2 as determined by area under the curve (AUC) kinetics in an ELISA measuring anti-S1 (USA_WA1/2020) IgG (n = 20/per group). For panels b–d and h–j, points represent individual subjects, fitted curves reflect the Fit Spline algorithm, dotted lines represent the lower limit of detection, and numbers represent the geometric mean titers (GMTs) at a given timepoint. For panels e–g, data are presented as GMTs, error bars represent the 95% confidence interval, and fitted curves reflect the Sigmoidal 4-Parameter Logistic (4PL) regression algorithm. Panel a was created with BioRender.com. Panels b–j were generated using GrapPad Prism v9.4 software. See Source Data for complete data and Supplementary Fig. 2 for complete vaccination regimens scheme.
