Figure 3.

Vancomycin treatment before vaccination reduces influenza-specific antibody titers. (A) Rhesus macaques were orally treated with three 14 day courses of vancomycin (red rectangles), followed by one day without vancomycin, before vaccination with quadrivalent influenza vaccine (blue syringes). A fourth vaccination was performed without vancomycin pre-treatment (Day 173). Serum anti-influenza IgG was measured at multiple timepoints. Data are geometric mean and standard deviation. (B) Fecal samples collected throughout the study were subjected to 16s rRNA gene sequencing, and OTU richness (alpha diversity) was plotted. Data are mean and standard error. (C) Non-metric multidimensional scaling ordination of macaque microbiome communities, with community dissimilarity measured using the Bray–Curtis algorithm (beta-diversity). Samples from the vancomycin cohort taken at the time of vaccination after vancomycin treatment (Days 0, 28, 84) are shown in warm colors, while those taken at vaccination without preceding vancomycin treatment (Day 173) are shown in green. Additional samples from the vancomycin cohort between vaccinations, as well as all samples from the vehicle cohort, are shown in blue and labeled in the key as “Other”.