Figure 2.

Anti-CP IgG1 antibody (Ab) titers in mice immunized with the glycoconjugates. BALB/c mice were immunized intraperitoneally with tetra-bovine serum albumin (BSA) (A), hexa-BSA (B), and octa-BSA (C) conjugates adsorbed on aluminum hydroxide twice over 14 days at 1.25–10 µg/dose (the hexa-BSA conjugate was injected at 2.5–10 µg/dose). Anti-CP IgG1 Ab titers in murine blood sera were determined by enzyme-linked immunosorbent assay 2 weeks after the second immunization. Streptococcus pneumoniae type 14 bacterial CP was used as the coating antigens. The data from two experiments were summarized. For each glycoconjugate, blood was taken from 6 to 12 mice. The data represent individual anti-CP IgG1 Ab titers, bars indicates median ± SD. Mann–Whitney Rank Sum tests were used to evaluate significance. Differences in the anti-CP IgG1 Ab titers between tetra-BSA and octa-BSA conjugates at the immunizing dose of 10 µg/mouse, *P < 0.05.