The only vaccine currently available for the prevention of tuberculosis in man is a live attenuated vaccine, bacille Calmette-Guerin (BCG), derived from Mycobacterium bovis. Concerns over the lack of the universal efficacy and safety of BCG have resulted in efforts to develop a new generation of TB vaccines. Historically, killed whole-cell preparations of mycobacteria have been ineffective vaccines. We revisited the potential of killed whole-cell vaccines by comparing their efficacy with live BCG Pasteur in a guinea pig challenge model. BCG Pasteur was inactivated with a low concentration of formalin and showed to be non-viable in culture or severe combined immunodeficient mice. Formalin-inactivated BCG was mixed with non-phospholipid liposome adjuvants (Novasomes™) and administered to guinea pigs as a single subcutaneous inoculation. All formulations were well tolerated and one conferred a significant survival advantage against lethal aerogenic challenge with M. bovis. Crown
Bibliographical noteFunding Information:
We thank the Animal Services Units at VLA Weybridge and CAMR. This work was supported by the Ministry of Agriculture, Fisheries, and Food, GB, now the Department of Environment, Food and Rural Affairs (DEFRA).
- M. bovis