How our immune system targets TB

MELBOURNE, MONDAY 31 OCTOBER, 2016: Every 18 seconds someone dies from tuberculosis (TB). It is the world’s most deadly infectious disease.

Mycobacterium tuberculosis, the causative agent of TB, has infected over one-third of the entire human population with an annual death toll of approximately 1.5 million people.

For the first time, an international team of scientists from Monash and Harvard Universities have seen how, at a molecular level, the human immune system recognises TB-infected cells and initiates an immune response. Their findings, published in Nature Communications, are the first step toward developing new diagnostic tools and novel immunotherapies.

Lead author, Professor Jamie Rossjohn, says one of the main reasons for our current lack of knowledge comes down to the complexity of the bacterium itself. Working with Professor Branch Moody’s team at Harvard, they have begun to gain key insights into how the immune system can recognise this bacterium.

Crucial to the success of M. tuberculosis as a pathogen is its highly unusual cell wall that not only serves as a barrier against therapeutic attack, but also modulates the host immune system. Conversely, its cell wall may also be the “Achilles’ heel” of mycobacteria, as it is essential for the growth and survival of these organisms. This unique cell wall is comprised of multiple layers that form a rich waxy barrier, and many of these lipid — also known as fatty acids — components represent potential targets for T-cell surveillance.

Specifically, using the Australian Synchrotron, the team of scientists have shown how the immune system recognises components of the waxy barrier from the M. tuberculosis cell wall.

“With so many people dying from TB every year, any improvements in diagnosis, therapeutic design and vaccination will have major impacts,” Professor Moody says.

“Our research is focused on gaining a basic mechanistic understanding of an important biomedical question, and may ultimately provide a platform for designing novel therapeutics for TB and treat this devastating disease,” Professor Rossjohn concludes.

—ends —

For Interview:
Professor Jamie Rossjohn

Media Contact:
Stephanie Pradier
+614 24 568 314
stephanie.pradier@monash.edu

FURTHER DETAILS:

Stats on TB:

http://www.theglobalfund.org/en/tuberculosis/

http://www.stoptb.org/resources/factsheets/

Professor Jamie Rossjohn is a Chief Investigator on the Australian Research Council Centre of Excellence in Advanced Molecular Imaging.

The $39 million ARC-funded Imaging CoE develops and uses innovative imaging technologies to visualise the molecular interactions that underpin the immune system. Featuring an internationally renowned team of lead scientists across five major Australian Universities and academic and commercial partners globally, the Centre uses a truly multi-scale and programmatic approach to imaging to deliver maximum impact.

The Imaging CoE is headquartered at Monash University with four collaborating organisations – La Trobe University, the University of Melbourne, University of New South Wales and the University of Queensland.

Professor Rossjohn is also a researcher at the Monash Biomedicine Discovery Institute.

Committed to making the discoveries that will relieve the future burden of disease, the newly established Monash Biomedicine Discovery Institute at Monash University brings together more than 120 internationally-renowned research teams. Our researchers are supported by world-class technology and infrastructure, and partner with industry, clinicians and researchers internationally to enhance lives through discovery.