New vaccine strategy tested in mice shows promise against TB
By ANIWednesday, January 26, 2011
LONDON - A research team has found that a new vaccine strategy tested in mice provides stronger, more long-lasting protection from tuberculosis (TB) infection than the vaccine currently used in humans, known as BCG.
Caused by the bacterium Mycobacterium tuberculosis (Mtb), TB remains one of the major causes of disability and death worldwide, with an estimated 1.7 million deaths in 2009 and increasing rates of drug-resistant disease.
The BCG vaccine, the only one approved for human use, provides some protection against initial TB illness but does not prevent latent infection, in which Mtb persists in human cells for years and may later develop into active disease.
The team of U.S. and European researchers combined two proteins previously found to improve the BCG vaccine’s effectiveness with a new component, a stress response protein that mice produce throughout the TB infection process.
This three-component vaccine, known as H56, was administered to uninfected mice before and after BCG vaccination.
Six weeks later, the mice were exposed to Mtb. The multistage strategy not only protected against initial illness, but controlled reactivation of latent infection and reduced Mtb levels in the lungs more effectively than BCG alone.
Because of the success of this study, the vaccine candidate is now entering clinical development.
Their findings were published online on January 23rd in the journal Nature Medicine. (ANI)