The New Zealand White rabbit was chosen because it is well characterized as a model for inhalational anthrax.17 In this initial study, we used polyinosinic:polycytidylic acid (poly I:C) as an adjuvant as we have demonstrated that it can generate robust antibody responses when formulated in DPX.18 Based on the dose finding experiment in mice (Fig. 1), rabbits were inoculated intramuscularly with a single dose of DPX-rPA (10 μg; Week 0) or three doses of alum-rPA (10 μg; Weeks 0, 4, and 16). This evidence concerns the gene RPA1 and anthrax infection.