(A) Glycan microarray analysis of pooled sera from Pneumovax 23-vaccinated humans (human reference serum mixture 007sp), rabbit ST8 typing serum, and a protective murine mAb 28H11 at different concentrations. Corresponding data are means + SD of 8 spots as technical replicates. (B) Inhibition of antibody binding by pre-adsorption with native ST8 CPS. Data are means + SD of 8 spots as technical replicates. P values are determined by one-tailed, unpaired t test with Welch’s correction. Data are from one representative out of at least 2 independent experiments. MFI, mean fluorescence intensity. n.s., not significant.