Primary and secondary antigen-specific antibody response over time following rPA + alum immunization. A, Binding response curves for individual serum samples collected over time following rPA alone or rPA + alum immunization show the effect of time and adjuvant on antibody response development. B, Maximum binding response (derived from data shown in A) of serum antibodies from mice given rPA + alum with or without rPA boost on day 71. C, Positive correlation of binding response and equivalent antibody concentration in rPA + alum + rPA boost mice over time. D, Dissociation rates of serum antibodies collected over time following rPA + alum immunization alone or with antigen boost on day 71. E, Serum antibody avidity score over time in mice given primary rPA + alum immunization only or those given primary immunization + rPA boost on day 71. Error bars indicate standard error of the mean of 3 (n=3).