Research finds new mechanism that can cause the spread of deadly infection

April 20, 2018, University of Birmingham
The Pacific Northwest strain of Cryptococcus gattii has gained the ability to infect otherwise healthy individuals. Credit: University of Birmingham

Scientists at the University of Birmingham have discovered a unique mechanism that drives the spread of a deadly infection.

Cptococcosirys is a rare and deadly fungal infection that affects the lung and brain and usually only occurs in people with impaired immunity.

However, one strain of the fungus – known as the Pacific Northwest strain of Cryptococcus gattii - has gained the ability to infect otherwise healthy individuals.

Cryptococcus gattii was considered a tropical fungus primarily found in places like Brazil, New Guinea and Australia, but it was found to be the cause of the Pacific Northwest Outbreak of Cryptococcosis in the US and Canada which began in 1999 and has seen hundreds of humans and animals being infected.

The infection affects the lungs first, because it is acquired by inhaling fungal spores. In the absence of therapy, and sometimes despite it, the infection quickly spreads to the brain and other organs with often fatal consequences.

Those infected with the disease have to undergo antifungal therapy that can last months - but those drugs often fail to curtail the disease and instead surgery is required to remove the infection from the lungs and central nervous system.

Lead author Dr Ewa Bielska, of the University of Birmingham's School of Biosciences, said: "It is vital that new drugs are developed to combat this disease, and in order to do that we need to find out how the disease spreads.

"Four years ago the University of Birmingham carried out research which demonstrated that the high virulence of this Cryptococcosis gattii strain results from its remarkable ability to grow rapidly within human white blood which relies on a unique 'division of labour' mechanism within the infection.

"To achieve this, individual fungal cells must work together to coordinate their behaviour, but how they do this has, up until now, been unknown."

Now the University of Birmingham's latest research, funded by the European Research Council and published in Nature Communications, has discovered that this 'division of labour' can be triggered over large cellular distances and is mediated through the release of microscopic fluid-filled "bags" called extracellular vesicles.

Professor Robin May, Director of the University of Birmingham's Institute of Microbiology and Infection, said: "These vesicles act like 'carrier pigeons', transferring messages between the fungi and helping them to coordinate their attack on the host cell.

"This is a previously unknown phenomenon in infectious disease, but also provides us with a potential opportunity to develop that work by interrupting this communication route during an ."

Professor May said that the latest findings were unexpected. He added: "Our initial expectation was that the fungus would only be able to communicate within a single host cell, but in fact we discovered that it can communicate over very large - in microbiology terms - distances and across multiple barriers.

"The fact that this long-distance communication turns out to be driven by extracellular vesicles' is even more intriguing.

"Our research continues and is still at an early stage, but ultimately we could envisage developing drugs that interrupt this signalling pathway between fungi in order to confuse them and prevent spread in the patient."

Explore further: Study identifies a new way to prevent a deadly fungal infection spreading to the brain

More information: Ewa Bielska et al. Pathogen-derived extracellular vesicles mediate virulence in the fatal human pathogen Cryptococcus gattii, Nature Communications (2018). DOI: 10.1038/s41467-018-03991-6

Related Stories

Study identifies a new way to prevent a deadly fungal infection spreading to the brain

August 16, 2017
Research led by the University of Birmingham has discovered a way to stop a deadly fungus from 'hijacking' the body's immune system and spreading to the brain.

Study points to opening of the Panama Canal as the gateway of Cryptococcus gattii migration from Brazil to Canada

January 18, 2018
In what is being described as "The Teddy Roosevelt effect," a deadly fungus in the Pacific Northwest may have arrived from Brazil via the Panama Canal, according to a new study led by the Translational Genomics Research Institute ...

Researchers explore little-known, deadly fungal infections

April 10, 2018
A new study by Althea Campuzano, Ph.D. a student at The University of Texas at San Antonio, and Floyd Wormley, Jr., Professor of Biology and Senior Associate Dean for Research and Graduate Studies, sheds light on little-known ...

Novel trick helps rare pathogen infect healthy people

October 17, 2014
New research into a rare pathogen has shown how a unique evolutionary trait allows it to infect even the healthiest of hosts through a smart solution to the body's immune response against it.

Angina drug could inform a new strategy to fight cryptococcosis

June 7, 2016
A drug, more commonly used in the treatment of angina, could be the focus of a new strategy in fighting the fatal fungal infection cryptococcosis.

New study targets lethal fungal infection

July 24, 2017
The development of new drugs to fight a common fungal pathogen which kills half a million people globally each year is a step closer thanks to a University of Queensland-led study.

Recommended for you

Study identifies a key cellular mechanism that triggers pneumonia in humans

December 11, 2018
The relationship between influenza and pneumonia has long been observed by health workers. Its genetic and cellular mechanisms have now been investigated in depth by scientists in a study involving volunteers and conducted ...

Human antibody discovery could save lives from fungal killer

December 11, 2018
A new way to diagnose, treat and protect against stealth fungal infections that claim more than 1.5 million lives per year worldwide has been moved a step closer, according to research published in Nature Communications.

Effect of oral alfacalcidol on clinical outcomes in patients without secondary hyperparathyroidism

December 11, 2018
Treatment with active vitamin D did not decrease cardiovascular events in kidney patients undergoing hemodialysis, according to a research group in Japan. They have reported their research results in the December 11 issue ...

Dialysis patients at risk of progressive brain injury

December 10, 2018
Kidney dialysis can cause short-term 'cerebral stunning' and may be associated with progressive brain injury in those who receive the treatment for many years. For many patients with kidney failure awaiting a kidney transplant ...

Silicosis is on the rise, but is there a therapeutic target?

December 6, 2018
Researchers from the CNRS, the University of Orléans, and the company Artimmune, in collaboration with Turkish clinicians from Atatürk University, have identified a key mechanism of lung inflammation induced by silica exposure, ...

PET scans to optimize tuberculosis meningitis treatments and personalize care, study finds

December 6, 2018
Although relatively rare in the United States, and accounting for fewer than 5 percent of tuberculosis cases worldwide, TB of the brain—or tuberculosis meningitis (TBM)—is often deadly, always hard to treat, and a particular ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

mrburns
not rated yet Apr 21, 2018
Some indication as to why or how the messaging benefits the bacteria would be nice.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.