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Bioniche Life Sciences is one step closer to marketing a new vaccine
that could save North America's cattle industry millions of dollars
annually. It's an innovation that might never have happened had it not
been for three university scientists and the Canadian Bacterial Diseases
Network, which brought them together.
The Canadian cattle industry has weathered several storms in recent
years, the most devastating of which has been bovine spongiform encephalopathy
(BSE), or mad cow disease. But what most people don't know is that the
North American cattle industry loses $1 billion annually because of bovine
respiratory disease (BRD), commonly known as shipping fever. Haemophilus
somnus (H. somnus) is one of the major pathogens associated with shipping
fever and one of the leading bacterial causes of economic loss to beef
producers. Vaccines for H. somnus have been on the market for 15-20 years,
yet more cases appear every year.
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H. somnus was originally identified decades ago as causing a neurological disorder in cattle called infectious thrombotic meningoencephalitis. Since that time, the organism has been associated with a number of other disease manifestations, including pneumonia, arthritis, myocarditis and septicemia. These are collectively referred to as bovine hemophilosis.
The cost of bovine respiratory disease extends beyond animal deaths. Other losses are sustained in the form of reduced weight gains, antibiotics and poor quality meat and hide products.
For Canada's struggling beef industry, a more effective vaccine could mean a savings of at least $25 million per year. "What it means for cattle farmers is essentially the availability of a tool to reduce economic losses," says Dr. Andrew Potter, a researcher at the Vaccine and Infectious Disease Organization. |
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"Clearly that's an indication that these vaccines need improvement in their ability to protect against respiratory infection," says Dr. Andrew Potter, a molecular bacteriologist at the University of Saskatchewan's Vaccine and Infectious Disease Organization (VIDO). Dr. Potter, who started the project, along with VIDO's Director Dr. Lorne Babiuk and Dr. Anthony Schryvers at the University of Calgary, have developed what they think could be the answer to the H. somnus problem.
Scattered across Western Canada, the scientists found each other through the Canadian Bacterial Diseases Network (CBDN), a Network of Centres of Excellence. "I met Andy (Potter) and Lorne Babiuk through CBDN meetings," says Schryvers. "That's what prompted us to explore using these receptor proteins in veterinary pathogens."
Schryvers came aboard through his longstanding interest in specific proteins that are involved in iron acquisition in pathogenic bacteria. He says they are ideal targets for vaccines because of the critical function they play as transferring-binding proteins. "We thought we had complementary expertise that would be needed to develop the vaccine," explains Potter.
Their goal was to identify which proteins the bacteria uses to acquire nutrients in the host - in this case, iron. The theory was that if cattle were vaccinated with these proteins and developed antibodies against them, bacteria would not be able to obtain this critical nutrient and would die.
What differentiates this team's vaccine from those already on the market is its use of recombinant DNA technology, which allows large quantities to be made in a very pure form. The result is a safer product capable of inducing a better immune response than conventional vaccines.
A series of vaccine trials conducted over four-to-five years proved their theory. One of the two proteins they used - TbpB - is involved in iron acquisition and appears to be a protective antigen. A second protein, LppB, is a major protective antigen produced by all strains of H. somnus examined to date.
CBDN provided early-stage funding to demonstrate proof of concept for the work, which Potter says is "absolutely critical" and helped to protect the intellectual property. "No company is going to get involved if you can't show that it actually works."
Having proven that the vaccine works in a controlled setting with material produced in a research laboratory, the next stage is demonstrating that vaccine produced under commercial manufacturing conditions is effective in both small- and large?scale trials. Their commercial partner, Bioniche Life Sciences Inc. of Belleville, Ontario, will make the large number of doses needed to carry out these efficacy studies.
Potter adds that CBDN's expertise in technology transfer will help accelerate the vaccine's move into the marketplace. "Any time you deal with partnerships, especially with the commercial sector, there needs to be one body that can deal with the external interactions."
Schryvers agrees that the network was important in the discovery. "That's one of the values of CBDN, that these kinds of relationships develop over the years and you see some basic research actually get into application," he says.
The CBDN's managing director stresses, however, that the researchers deserve all the credit for the development. "They are really the ones who are going to take the technology further into developing a new vaccine," says Ying Gravel. "CBDN has funded the work, but ultimately it's a good thing that has gone out into the user sector to be developed into a real product."
www.cbdn.ca
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