Source: Griffith University
Researchers led by Griffith University's Professor Mark von Itzstein have developed a technique to enable scientists to study the H5N1 avian influenza virus more easily.
Published in the chemistry journal This approach will enable the rapid identification of flu viruses that have attained the capacity to recognise human receptors, the researchers said.
The Griffith team collaborated with a team at the Hong Kong University-Institut Pasteur led by Professor Malik Peiris, who developed a method to insert the H5 protein into a virus-like particle.
"To better interrogate a virus protein, researchers need to be able to observe and monitor the way it functions when associated with a virus particle," von Itzstein, from Griffith's Institute for Glycomics, said.
"It's similar to the way it would be difficult to work out how a gun functions by only studying a bullet."
The use of these virus-like particles as a vehicle for the virus protein enables researchers to work without the need for high-containment laboratory procedures mandatory for handling live virus.
"Importing, transporting and studying a highly contagious live virus has always held some level of inherent risk for research staff, the wider community and agricultural economy," von Itzstein said.
"There are particularly strict regulations in a country such as Australia, in which the virus is not endemic.
"In the past this has restricted the ability of Australian researchers, and those of any country in which a disease is not endemic, to base research programs within their own institutes."
He said while H5N1 had currently evolved to the stage where it can be transmitted from birds to humans, and there is now evidence mounting that it can also cause limited human-to-human transmission.
"The H5 protein is located on the surface of the bird flu virus, and acts like a biological glue enabling it to recognise and bind to certain carbohydrates on living cells," he said.
"The emergence of a pandemic human influenza virus from a bird flu parent appears to involve this protein developing an ability to switch from binding to the most common carbohydrate in a bird's digestive tract, to binding to the common carbohydrate in the human upper respiratory tract."
He said the 1918 Spanish Flu, which killed 50 million people worldwide, was strikingly similar to the current avian flu.
"The mutation of just one amino acid in the protein-binding site appeared to determine the 1918 virus' preference for human carbohydrates. There's no reason why H5N1 couldn't do the same, resulting in a human pandemic."
He said it was thought that some 19 strains of influenza A have now shown levels of resistance to Tamiflu, the most widely used flu treatment.
"This evolutionary trend could be expected to continue, rendering some of our international drug stockpiles useless," he said.
von Itzstein, who co-developed the first novel carbohydrate-based influenza treatment Relenza, now leads Australia's only institute dedicated to the science of glycomics - the study of the role of carbohydrates in healthy biology and disease.
It will use the discovery in the quest for carbohydrate-based anti-viral 'plug' drugs, able to block the ability of disease to replicate and spread through the body.
