Improvements in the Prevention and Treatment of Anthrax Infection

Synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG motifs mimic the immunostimulatory activity of bacterial DNA. CpG ODN are finding use as vaccine adjuvants based on their ability to increase the speed, magnitude and duration of vaccine-specific immune responses. We conducted studies examining the capacity of CpG ODN to accelerate and prolong the protection induced by AVA (Anthrax Vaccine Adsorbed). Co-administering CpG-adjuvanted AVA with Dalbavancin, a long-activity antibiotic, protected naive mice from both the immediate and long-term threat posed by exposure to anthrax spores. A majority of animals immunized only once with CpG-adjuvanted AVA maintained resistance to anthrax infection for more than one year, even after their Ab titers declined to sub-protective levels. This survival was mediated by the de novo production of protective Abs by high affinity long-lived memory B cells that were generated by vaccination with CpG-adjuvanted AVA.