Nanotechnology against bioterror

Anthrax is an infectious and often deadly bacterial disease spread by contact with infected animals, handling infected products, eating infected meat or breathing anthrax spores.

A company in Illinois, USA, is developing a new anthrax vaccine containing calcium phosphate nanoparticles.

These nanoparticles are part of an adjuvant developed by BioSante Pharmaceuticals. An adjuvant is a substance which, when added to a vaccine, boosts the size of the resulting immune response.

The new vaccine will contain both anthrax antigens (to stimulate an immune response targeted against the anthrax bacterium) and the new adjuvant (to heighten the immune response).

At the moment, the only approved anthrax-vaccine adjuvants are aluminium salt (alum) derivatives (e.g. aluminium hydroxide gel). But these can cause irritation and inflammation at the injection site, or an allergic reaction.

By contrast, calcium phosphate is a naturally occurring compound found in teeth and bones. Multiple studies have shown that the nanoparticle-containing adjuvant doesn't cause inflammation at the injection site, and no allergic response has been seen.

Moreover, it can be taken by mouth or through the nose – it doesn't have to be injected. This is likely to be more appealing to patients, and may encourage more people to have the vaccination.

BioSante is also working with the US Centers for Disease Control and Prevention, and the US Navy and Army to develop vaccines against malaria, anthrax, ricin, staph and bubonic plague.