Progress in treating tuberculosis

Recent animal research has led to new developments in the detection and treatment of the infectious disease tuberculosis (TB).

In a study led by the Rosalind Franklin Institute, UK, researchers developed a more accurate way to scan for TB using a chemical compound called a radiotracer, which gives off radiation that can be detected with a PET scan and turned into an image. 

When the radiotracer, FDT, was given to different animals infected with TB, including rats, rabbits and marmoset monkeys, it was taken up by TB bacteria in the body with no signs of toxicity.

Although PET scans are already used to identify signs of lung inflammation (a common feature of TB), they are not specific to TB – the latest approach uses a new FDT with a carbohydrate that is only processed by TB bacteria and is now ready to be trialled in people.

Ben Davis, at the Franklin, said: “Finding an accurate way to identify when TB is still active in the body is not only important for initial diagnosis, but to ensure patients are receiving antibiotics long enough to kill the disease, and no longer.”

Meanwhile, a team at the Butantan Institute, Brazil, used mice to understand why a version of the BCG vaccine, used for TB, is more effective at protecting against infection.

99% of mice given a genetically modified ‘recombinant’ version of the BCG vaccine were protected (compared to 90% with the standard version), and by analysing the genes involved in the immune response and comparing tissues between vaccinated and unvaccinated mice, the researchers saw marked differences, for example in which genes were activated, between the two vaccine types.

The findings provide new insights into how to improve TB prevention through vaccination, which starts to wane in adulthood.