Serum IgG responses at different time points against (A) O-specific polysaccharide (OSP) and (B) tetanus toxoid (TT) in various vaccine cohorts following intramuscular (IM) or intradermal (ID) immunization with various doses (based on OSP component) and/or loading ratios of OSP to TTHc, with or without adjuvant alum.

Mice were immunized on days 0, 21, and 42. Responder frequency reflects a 15-fold increase over baseline for anti-OSP IgG, and 30-fold increase for anti-TT IgG. An asterisk denotes a statistically significant difference (P<0.05) in the mean response from baseline (day 0) level.