Figure A7.

S protein in rabbit serum samples after coincubation with anti-spike antibody containing serum. Spike-containing serum from Day 1 after dosing with Ad26.COV2.S (in red) was coincubated with anti-spike antibody containing serum from 28 days after dosing with Ad26.COV2.S (in blue). Spike-containing serum from Day 1 after dosing (in red) was coincubated with predose serum (from Ad26.COV2.S immunized group—Column 4, or Ad26.ZIKV.001 immunized group—Column 6) or anti-spike antibody deficient serum of rabbits dosed with Ad26.ZIKV.001 (in blue) (negative controls). The dotted line represents the lower limit of detection (LOD) of the assay based on the standard curve. Comparison of the S protein concentration was performed using unpaired t-tests with Welch’s correction. The geometric mean is represented with a red line. ** p < 0.01.