Livers fight back and kill the killers… Einstein was right (dark energy is real)… prizes and other stories

Bulletins, Media bulletins

A T-cell (blue/green) fully engulfed by a mouse liver cell (red). The two blue circles are the cell nuclei of the liver cell. (Patrick Bertolino/Centenary Institute)Our livers can fight back against the immune system—reducing organ rejection but also making us more susceptible to liver disease.

In this bulletin:


Scientists at the Centenary Institute in Sydney have seen for the first time (in mice) how the liver goes independent, engulfing and destroying the body’s defence troops—T-cells.

Their discovery, featured on the cover of PNAS (Proceedings of the National Academy of Sciences) this week, opens the way to both new approaches to transplant rejection, and to the fight against hepatitis and other chronic liver diseases which affect over 200,000 Australians and hundreds of millions of people worldwide.

Dark energy: Also coming up, young Queensland astrophysicist Tamara Davis will be speaking in Tasmania, South Australia and Victoria about dark energy over the next few weeks. She and her colleagues from the WiggleZ team have found evidence that dark energy is real and that therefore Einstein’s General Theory of Relativity is on the money. She says it’s time to find some new questions. She’s available for interviews this week and next.

The Prime Minister’s Science Prizes will be announced at a formal dinner on Wednesday 12 October 2011 and we can now brief journalists from long-lead publications under embargo.

In other dates for the calendar – the Centenary Institute Lawrence Creative Prize will be awarded in Sydney on Wednesday 19 October and the $50,000 CSL Florey Medal will be announced in Parliament House, Canberra, on Monday 21 November.

And next February the nation’s science communicators and journalists will meet in Sydney for the Australian Science Communicators National Conference, 27 to 29 February, 2012. More details nearer the time.

Contents:

How our liver kills “killer cells”


Our livers can fight back against the immune system—reducing organ rejection but also making us more susceptible to liver disease.

Scientists at the Centenary Institute in Sydney have seen for the first time (in mice) how the liver goes independent, engulfing and destroying the body’s defence troops—T-cells.

Their discovery, published this week in PNAS (Proceedings of the National Academy of Sciences), opens the way to both new approaches to transplant rejection, and to the fight against hepatitis and other chronic liver diseases which affect over 200,000 Australians and hundreds of millions of people worldwide.

“In 2004, we discovered that healthy liver cells can engulf active immune cells, known as T-cells—and now we’ve seen that those T-cells are actually destroyed,” says Dr Patrick Bertolino, the leader of the research team at the Centenary Institute.

“The liver is an amazing organ,” Dr Bertolino says. “Most people think it just breaks down alcohol, but it’s the factory of the body – breaking down substances we don’t want and making the ones that we do.

“We now know liver cells also have the ability to subvert the orders of the immune system,” he says, “Our discovery might explain why liver transplants have lower rejection rates than other organ transplants.”

“When Patrick first told me he had evidence T-cells might be eaten by liver cells, showing a possible link to the liver’s ability to dial down the immune response, I thought the idea was crazy,” says lead author Volker Benseler. But Volker accepted Patrick’s challenge to prove it and went on to find healthy mouse liver cells eating T-cells, which was unexpected as this ‘cell cannibalism’ had only previously been seen in tumour cells.

One potential benefit of the research is reducing rejection in organ transplants. About 200 liver transplants are performed in Australia each year and up to 25 per cent of cases end in rejection.

In transplantation, the new organ is seen by the body as a foreign object: the spleen or lymph nodes tell naïve T-cells to replicate and turn into killer T-cells, which are sent off to invade and kill the ‘foreign’ cells.

What the researchers have discovered is the liver goes around this process: liver cells signal to naïve T-cells and digest them before they have a chance to become killer T-cells.

Centenary Institute’s Liver Unit leader, Professor Geoff McCaughan, says the cocktail of immunosuppressive drugs that organ transplant patients receive reduce the odds of organ rejection but makes patients’ immune systems weak, leaving them open to serious infection from otherwise minor illnesses like cold or flu. These drugs also predispose the patient to long-term heart disease and cancer. “If we can harness the way the liver controls T-cells, then long-term there is a chance that transplant patients won’t need these drugs,” he says.

Another spin-off of this latest work could be to find a way to dial down the liver’s destruction of T-cells, increasing the liver’s defence against infections like hepatitis.

In Australia, 217,000 people are living with chronic hepatitis C and it is estimated that 170 million people worldwide are infected with hepatitis C, for which there is no vaccine.

Exploiting signalling pathways between the liver and the T-cells is one possible outcome of this discovery, but first the molecular biology that underpins those pathways will need to be worked out.

“It could be another ten years plus before we see drugs derived from this work enter clinical trials,” Dr Bertolino says.

However, the research opens up a new question—why? “We don’t yet know why the liver has developed this ability,” says Dr Bertolino. “The discovery reminds us that we still have a lot to learn about the liver.”

The work was conducted at the Centenary Institute and at Sydney’s Concord RG Hospital, at the ANZAC Research Institute and CERA. Dr Benseler is now completing surgical training in Germany.

To access high resolution  images and background information go to http://www.scienceinpublic.com.au/centenary

For more information: call Andrew Wight on (03) 9398 1416, 0422 982 829

For interviews contact: Patrick Bertolino, 0402 850 402

Tamara Davis and the hunt for dark energy: the AIP Women in Physics lecture tour

Tamara Davis, an award-winning astrophysicist from the University of Queensland, is the 2011 Australian Institute of Physics Women in Physics lecturer. The AIP have now announced a number of dates for her public lectures.

The dark side of the Universe

Observations of the universe over the last few decades have thrown us some curve balls.

We thought we had the basic picture—the universe is expanding, and all the structure we now see formed thanks to gravity out of little over-dense clumps in the hot, dense, early universe. Well that was all true, but we’ve realised that that’s not the end of the story. There’s a dark side to the universe that we don’t usually see, and it seems that everything we thought we knew makes up only 5 per cent of the universe! Dark matter and dark energy make up the rest.

In her talk Tamara will explain why we are so certain of such a seemingly ludicrous proposition, and what we can hope to learn by studying these wild and wonderful phenomena.

Tamara is available for media interviews this week and next.

Public lectures

Dates Details
Friday 9 September 7 pm, Wollongong Science Centre, Wollongong, NSW(Note: 7pm start, not 7.30pm)
Tuesday 13 September 6.30 pm, Sydney Observatory, NSW
Thursday 15 September 6pm, Huxley Lecture Theatre, ANU, ACT
Wednesday 28 September 8pm, Physics Lecture Theatre1, Sandy Bay Campus, University of Tasmania, TAS
Thursday 29 September 6.30pm, RiAus Science Exchange, 55 Exchange Place, Adelaide, SA
Wednesday 12 October 10am, VSSEC (The Victorian Space Science Education Centre), Strathmore, Vic

 

Tamara will also be giving over a dozen talks to school students and teachers in capital cities and regional towns, as part of the lecture tour. Details at http://bit.ly/p1c4Ej

Prime Minister’s Science Prizes

The Prime Minister’s Science Prizes will be announced at a formal dinner in Parliament House Canberra on Wednesday 12 October 2011 and we can now brief journalists from long-lead publications under embargo.

The Prime Minister’s and Science Minister’s Prizes for Science are the nation’s awards for distinction in science and science teaching.  The five prizes are:

  • Prime Minister’s Prize for Science
  • Science Minister’s Prize for Life Scientist of the Year
  • Malcolm McIntosh Prize for Physical Scientist of the Year
  • Prime Minister’s Prize for Excellence in Science Teaching in Primary Schools
  • Prime Minister’s Prize for Excellence in Science Teaching in Secondary Schools.

For more information, contact Niall Byrne on http://www.innovation.gov.au/Science/InspiringAustralia/PrimeMinistersPrizesforScience/Pages/AboutthePrizes.aspx

CSL Florey Medal

Sir Howard Florey took penicillin from an idea to a drug that has literally saved hundreds of millions of lives.

To honour those treading in his footsteps, the Australian Institute of Policy and Science (AIPS) will present the $50,000 CSL Florey Medal for 2011 in Parliament House, Canberra, on Monday 21 November at the annual dinner of the Association of Australian Medical Research Institutes.

For further information visit www.aips.net.au or contact Elektra Spathopoulos, Executive Director, Australian Institute of Policy and Science & the Tall Poppy Campaign

Tel: (02) 9351 0819, Mob: 0425 433 954, email: director@aips.net.au.

Centenary Institute Lawrence Creative Prize

The Centenary Institute Lawrence Creative Prize is a $25,000 award for outstanding creativity in biomedical research by young scientists.

The award is named in honour of Neil Lawrence who was inaugural chair of the Centenary Institute Medical Research Foundation.

The Prize will be awarded in Sydney on Wednesday 19 October, 2011.

More information: http://www.centenary.org.au/p/about/whatson/lawrencecreative/