FIG 1.

Imject Alum-adsorbed CTD1 stimulates primary and recall IgG1 responses. C57BL/6 mice were immunized s.c. with Imject-adsorbed CTD1. Mice received a booster vaccine consisting of CTD1 in PBS on day 60. Sera were collected at the times indicated, and endpoint CTD1-specific IgG1 titers were determined by ELISA for mice immunized with 25 μg (top), 50 μg (middle), or 100 μg (bottom) of CTD1. Each data point represents an individual mouse. Statistical significance was determined by ANOVA and is indicated by asterisks: **, P = 0.01 to 0.001; ***, P < 0.001. The day 60 titers were compared for each immunization by ANOVA, and titers were significantly higher for the 100-μg dose than the 50-μg or 25-μg dose (P < 0.001).