How our gut’s immune cells see invaders; what’s happening to WA’s coral reefs?

Media bulletins, Other

This morning Monash, Melbourne, and UQ have a cracking paper in Nature announcing the discovery of a key that wakes up a poorly understood part of our immune system.

It’s the next step for the research which last year won the Eureka Prize for Scientific Research.

Two years ago they discovered that ‘mystery’ immune cells in our gut detect invaders by reacting to components of vitamin B that are only made by certain bacteria and fungi. Now they have a molecular key to turn this off and on.

It’s complex science. But I think it will be one of those papers we’ll look back on in years to come and realise that it was the beginning of a new way of understanding the immunology of our gut and how we might tackle inflammatory bowel disease, peptic ulcers and even TB.

Meanwhile, the impact on warmer oceans and rising sea levels on WA’s coral reefs has been measured looking at growth rings dating back to 1795.

A team from AIMS, UWA, CSIRO and overseas examined long coral cores, which have annual growth bands similar to tree rings.

These allowed the scientists to look at patterns of climate variability back to 1795 – seven years after the First Fleet landed at Botany Bay.

The coral cores told them that recent extreme weather events off the WA coast are highly unusual – and happening more often.

Read on for more…

 

Turning on our immune sentries

Melbourne, Monash, UQ and the synchrotron find what sends our MAITs into action to protect our gut from invaders

Our guts, lungs and mouths are lined with mysterious immune cells that make up to ten per cent of the T cells in our immune system. Last year Australian researchers showed that these cells act as sentinels against invading bacteria and fungi. Now they’ve identified the precise biochemical key that wakes up these sentries and sends them into action.

The patented work, published in Nature today, provides the starting point to understanding our first line of defence, and what happens when it goes wrong.  It will lead to new ways of diagnosing and treating inflammatory bowel disease, peptic ulcers and even TB. It could also lead to novel protective vaccines.

The discovery is the result of national and international collaboration between the universities of Melbourne, Monash, Queensland and Cork. It also depended on access to major facilities including the Australian Synchrotron and the Bio21 Institute.

Last year members of the research team won an Australian Museum Eureka Prize for determining that these immune cells, known as mucosal-associated invariant T cells (MAITs), detect reactive intermediates in the synthesis of vitamin B2 (riboflavin) that is made by many invasive bacteria and fungi. The latest discovery narrows the trigger down to a small group of compounds produced by specific bacteria and fungi, which may be associated with several diseases.

“We have unlocked a secret that will enable our team to investigate the role that MAIT cells play in health and disease, which is exciting,” says Dr Alexandra Corbett, a lead author on the study from the University of Melbourne. “However, there are major international laboratories with whom we have to compete.”

“This is an excellent example of how collaborative research in Australia can bring groups with expertise in different areas together to make significant advances,” says joint leader Prof Jim McCluskey, Deputy Vice-Chancellor (Research) of the University of Melbourne.

More information and the full paper at www.scienceinpublic.com.au/arc-imaging

For interviews

  • Professor Jamie Rossjohn, Monash University, jamie.rossjohn@monash.edu; Work phone: +61 3 9902 9236
  • Professor Jim (James) McCluskey, DVC Research, The University of Melbourne, jamesm1@unimelb.edu.au
  • Professor David Fairlie, Institute for Molecular Bioscience, The University of Queensland, d.fairlie@imb.uq.edu.au, Work phone: +61 7 3346 2989

Corals don’t lie: centuries of rising sea levels and temperature data revealed

Warmer oceans and rising sea levels are having a severe impact on Western Australia’s coral reefs, according to research published in Nature Communications this week from the Australian Institute of Marine Science, together with a team from The University of Western Australia, CSIRO and the University of San Diego

Coral cores from the eastern Indian Ocean have shown how the unique coral reefs of Western Australia are affected by changing ocean currents and water temperatures – and the researchers warn that future extreme events could have “potentially significant consequences for the maintenance of Western Australia’s unique marine ecosystems”.

The study looked into how La Niña, a climate swing in the tropical Pacific, has affected the warm Leeuwin current which flows off the western coast of Australia over the past 200 years.

The team examined coral cores, which have annual growth bands similar to tree rings, allowing the scientists to look at patterns of climate variability back to 1795 – seven years after the First Fleet landed at Botany Bay.

La Niña events in the tropical Pacific strengthen the Leeuwin Current, bringing unusually warm water temperatures and higher sea levels to the ocean off southwest Western Australia.

In 2011, a heat wave along WA’s reefs led to coral bleaching and fish kills.

The team found that the strong winds and extreme weather of that year were highly unusual, and warn that future La Niña events will have significant consequences for WA reefs, including the Ningaloo Reef World Heritage site.

In addition to warming sea surface temperatures, the team also found that sea-level variability and Leeuwin Current strength have increased since 1980 – clear evidence that global warming and sea-level rise is increasing the severity of these extreme events.

Read more from AIMS

For interviews, please contact:

  • Dr Jens Zinke, Assistant Professor at the University of Western Australia Oceans Institute and AIMS-UWA scientist, jens.zinke@uwa.edu.au, 08 63694029
  • Georgina Kenyon, Australian Institute of Marine Science, +61 (0)7 4753 4265, g.kenyon@aims.gov.au