Researchers to replace 'needle in a haystack' technique in developing vaccine

Flea research-team member Dr Cassandra Lawson gets a 'thank you' kiss in advance from Tammie, surrounded by (anti-clockwise) Dr Mandy Burrows, Dr Wayne Greene and Professor Andrew Thompson.

"It was like looking for a needle in a haystack — now we are looking for the same needle in a small bale of hay."

That's how Murdoch University parasitologist Professor Andrew Thompson and molecular biologist Dr Wayne Greene describe the scenario they and their research colleagues face in finding a vaccine to combat the scourge of modern-day domestic pets — fleas.

'Unbelievable advances in molecular biology' give Murdoch's multi-disciplinary vaccine research team an excellent chance of producing a highly-effective and commercially-attractive anti-flea vaccine.

The project was sparked by the reunion of Professor Thompson and Dr Greene, who worked on an earlier phase of the anti-flea research nearly a decade ago.

"There is a successful precedent for developing a vaccine to combat external parasites," Dr Greene said. "It took the CSIRO 20 years to develop a successful vaccine against the cattle tick.

"They had to use the 'needle-in-the-haystack' approach but, with the new techniques available to us — and the body of research we did in the early nineties — it is possible that we will have trials of an anti-flea vaccine within three years."

What the team is striving for is an 'across-the-board' flea-prevention vaccine, rather than a treatment for allergies caused by flea bites.

They are spurred on by:

• the idea of developing a biological control to replace chemical-based treatments for fleas;
• the knowledge that fleas are beginning to show signs of resistance to many chemicals used in products currently on the market; and
• the fact that fleas thrive in Western Australia's hot, dusty climate.

"Dogs, like us, are allergic to a lot more things than they used to be," Professor Thompson says. "That's a down-side of having cleaner pets.

"We have progressively removed many of the parasites their natural (antibody) defences used to be preoccupied with, such as worms, so some of these antibodies now appear to be involved in allergic responses."

The research team — which combines the specialist skills of dermatologist Dr Mandy Burrows; immunologist Dr Cassandra Lawson; parasitologist Dr Alan Lymbery and pharmacologist Associate Professor Jim Reynoldson, as well as Dr Greene and Professor Thompson — will have several goals:

• to find an effective diagnostic test for flea allergies;
• to develop a 'de-sensitising' agent — combatting the effects of flea-borne allergies through injection of small doses of the flea allergen; and
• to replace injections with an oral, anti-flea vaccine.

There are also prospects of identifying useful by-products from the fleas.

"It is known, for instance, that components of flea saliva are anti-blood-clotting agents," Dr Greene says.

"The development of new, anti-coagulants could be equally important in human medicine as in treatment of animals."

When Professor Thompson and colleagues, including Emeritus Professor John Penhale, started research on fleas 12 years ago the focus was on finding a way of treating the symptoms of animals allergic to flea bites.

Starting from the premise that one or two allergens caused the problem, and then finding a way to treat them, the research team confronted a much more complex situation. It turned out that each dog had a different profile that required an individual approach.

Professor Thompson compares it to a human having to undergo many different skin tests to find out exactly what they are allergic to — dust, pollen etc.

Now the research team is turning its attention to tackling the cause of the allergic reaction — the flea.

For that they will require tens of thousands of fleas. And to breed that number the team will employ another new piece of technology — an artificial dog.

The 'dog', developed in the United States for other aspects of flea research, allows the parasites to be securely contained and bred on a diet of blood supplied from an abattoir.

Biomedical research and development in Western Australia has received a substantial boost with the establishment of a joint venture institute involving Murdoch University and Curtin University of Technology.

The Western Australian Biomedical Research Institute (WABRI) is a $1million State Government-funded centre of excellence.

Murdoch's Division of Veterinary and Biomedical Sciences will host the Institute's Centre for Biomolecular Control of Disease, while the second, inaugural node of WABRI, the Centre for Molecular Technology and Therapeutics, will be based at the School of Biomedical Science at Curtin.

Professor Val Alder, Murdoch's Pro Vice-Chancellor (Research) and her Curtin counterpart, Professor Paul Rossiter, played a central role in establishing the joint venture.

The two nodes are headed by Murdoch's Professor Andrew Thompson and Curtin's Associate Professor Erik Helmerhorst.

Both universities have pledged major cash and in-kind support to ensure the Institute's success, and Deputy Premier and Minister for Commerce and Trade Hendy Cowan has indicated full support for the new institute's aim of promoting a high impact industry in biomedical R&D for WA.

Professor Thompson said the universities were making a pro-active commitment to building the integrated infrastructure and support structures to sustain world class R&D environments in the state.

"This initiative brings together world-class scientists from across the research sector to build a more integrated and strategic R&D focus in this burgeoning field," he says.

The formation of WABRI is in line with recommendations of the Will's review and the Federal Government's recognition of the future impact of biotechnology-related research in Australia.

The Murdoch-based Centre for Biomolecular Control of Disease (CBCD) combines a team of more than 30 biomedical scientists, formalising the already strong collaboration between these researchers.

The CBCD's research strengths in infectious diseases and pharmacology are recognised internationally through an extensive and diverse range of collaborative arrangements, including major links with industry, the World Health Organisation, and with university and government institutes in Australia, Europe and the USA.

Researchers in the CBCD have attracted more than $5million in research funding and generated over 100 research publications over the past five years.

The principal scientists in the CBCD are Dr Wayne Greene, Dr Cassandra Lawson, Associate Professor Jim Reynoldson, Dr Antony Armson, Professor Thompson, Dr Una Morgan, Dr Vanessa Cull, Dr Alan Lymbery and Dr Simon Reid.

The Centre's research focus is on

• Molecular basis of cancer
• Immunotherapy and DNA vaccines
• Anti-parasitic drug development
• Molecular parasitology, and
• Molecular epidemiology

The Centre for Molecular Technology and Therapeutics (CMTT) has a team of more than 45 biomedical scientists and postgraduate students, with an impressive record of providing innovative solutions to the health care, pharmaceutical and biotechnology industries.

CMTT's research focus is on

• Pharmacogenetics
• Molecular microbiology
• Diabetes and rational drug design
• Molecular and cellular mechanisms of asthma
• Molecular genetics, and
• Functional genomics

While WABRI has two, inaugural research nodes, it is structured to allow for future additions of nodes and programmes, providing the integrated framework for future expansion of biomedical science in Western Australia.

There is also flexibility within the Institute's structure, allowing for new nodes to be based in institutions or commercial organisations.

"Already there is significant interest by a number of leading scientists from academia and industry to form new nodes of the joint venture," Professor Thompson says.

"WABRI's programmes represent major research groupings that may overlap as part of collaborative and multi-disciplinary research activities.

"It will enhance the capacity of WA's leading biomedical scientists to generate new and innovative solutions within the health care, medical, pharmaceutical and biotechnology industries; and will strengthen this State's capacity to attract leading scientists, train world-class scientists and create jobs in new and emerging biotechnology-based industries."