Hope for threatened Tasmanian devils: Research paves way for vaccine development

Mar 11, 2013
Credit: Save the Tasmanian Devil Program

New research paves the way for the development of a vaccine for the Tasmanian devil, currently on the brink of extinction because of a contagious cancer.

It has been less than two decades since scientists discovered the contagious cancer (DFTD) which causes 100 per cent mortality in the endangered marsupials. The , which spreads when the devils bite each other's faces during fighting, kills its victims in a matter of months. As it has already wiped out the majority of the population with sightings of devils reduced by 85 per cent, scientists are desperate to find out more about the mysterious cancer which somehow manages to evade the devils' .

Until now, scientists have believed that the tumours were able to avoid detection by the immune system because the Tasmanian devils have very little (preventing the immune system from recognising the tumour as foreign). However, a University of Cambridge led collaboration with the Universities of Tasmania, Sydney and South Denmark has discovered that the explanation is more complex.

On the surface of nearly every are major histocompatibility complex (MHC) molecules. These molecules enable the immune system to determine if a cell is friend or foe, triggering an if the cell is foreign and a potential threat. The new research, published today, 11 March, in the journal PNAS, reveals that DFTD lack these critical molecules, thereby avoiding detection by the devils' immune system.

Credit: Save the Tasmanian Devil Program

Professor Jim Kaufman, from the University of Cambridge's Department of Pathology, said: "Once it was found that the cancer was escaping from the devils' immune system, scientists needed to figure out how."

The researchers found that the DFTD cells have lost the expression of MHC molecules, but that the genes that code for these molecules are still intact. This means that these genes could potentially be turned back on. Indeed, the scientists showed that by introducing signalling molecules such as interferon-gamma, a protein which triggers the immune response, the DFTD cells can be forced to express MHC molecules.

Dr Hannah Siddle, lead author of the paper from the University of Cambridge, said: "Developing a vaccine based on our research could tip the balance in the favour of the devil and give them a fighting chance."

"However, we still face some hurdles. The is evolving over time and any vaccine programme would have to take this into consideration. Also, because of the difficulties of vaccinating a wild population, it may be more efficient to use a vaccine in the context of returning captive devils to the wild."

Although the only other contagious cancer has been found in dogs (canine transmissible venereal cancer), the rapid development of DFTD highlights how quickly they can emerge.

Professor Kaufman added: "Our study has implications beyond the . Sooner or later a human strain of contagious cancer will develop, and this work gives us insight into how these diseases emerge and evolve."

Explore further: Orb-weaving spiders living in urban areas may be larger

More information: The paper 'Reversible epigenetic down-regulation of MHC molecules by devil facial tumour disease' will be published in the 11 March edition of PNAS.

Related Stories

Devil disease is immortal, new study finds

Aug 31, 2012

(Phys.org)—The outlook for Tasmanian devils appears even worse following breakthrough research by the University of Sydney published in PLoS One, today.

Culling can't save the Tasmanian devil

Oct 04, 2011

Culling will not control the spread of facial tumour disease among Tasmanian devils, according to a new study published this week in the British Ecological Society's Journal of Applied Ecology. Unless a way ...

Recommended for you

Orb-weaving spiders living in urban areas may be larger

Aug 20, 2014

A common orb-weaving spider may grow larger and have an increased ability to reproduce when living in urban areas, according to a study published August 20, 2014 in the open-access journal PLOS ONE by Eli ...

User comments : 0