Quantitative measurements of serum IgG antibodies specific for CTB_ET or CTB_cl in mice immunized with TcpF-A2-CTB_cl chimera, TcpF+CTB_ET, or CTB_ET.

<p>Day 42 serum samples were assayed for anti-CTB IgG amounts to either CTB_ET or CTB_cl. Each data point represents the anti-CTB IgG amount for an individual mouse. Anti-CTB IgG amounts specific for CTB_ET and CTB_cl in each individual mouse are connected with a line. Horizontal lines per group represent the geometric mean titer to either CTB_ET or CTB_cl. Above each grouping are the antigens that were used for immunization and the corresponding <i>P</i>-value obtained for within group comparisons. Statistical differences were analyzed using a two-tailed paired t-test, and <i>P</i>-values less than 0.05 were considered significant.