The objective of this study was to determine whether a DNA prime-protein boost immunization against the Bacillus anthracis protective antigen (PA) and lethal factor (LF) antigens could induce a protective immune response against significant aerosol challenge in the rabbit model. Rabbits were vaccinated with different regimens of DNA vaccines and aerosol challenged with B. anthracis spores, Ames strain, with an average dose of 50 LD50s with a range from 18 ...