Figure 4.

Anti-OS IgG1 antibody (Ab) titer in mice immunized with the OS-conjugates, CP, or bacteria. The biotinylated oligosaccharides tetra-biotin, hexa-biotin, and octa-biotin were applied as coating antigens. (A) Fourteen days after the second immunization, IgG1 Ab titers were determined in the pooled sera of BALB/c mice (n = 6) intraperitoneally vaccinated with a single dose (10 µg) of each conjugate adsorbed on aluminum hydroxide. (B) Fourteen days after the second immunization, the IgG1 Ab titers were measured in the pooled sera of two groups of BALB/c mice (n = 6) who were intraperitoneally vaccinated with single doses of either 1.1 or 2.2 µg (CP content) of Streptococcus pneumoniae type 14 CP-CPM₁₉₇ adsorbed on aluminum phosphate. (C) The level of IgG Abs in rabbits (n = 2) immunized with inactive S. pneumoniae type 14 bacterial cells. Ab titers were transformed to log₁₀. n = 6 assays per antiserum. The data are displayed as a mean value ± SD. Mann–Whitney Rank Sum tests were used to determine significance, *P < 0.05.