Prepare, Prevent, Respond, and Recover From Outbreak: The Development of Multiple Immunoassays Using a Single Antibody Against Bacillus Anthracis Protective Antigen

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By Shawn Lawrence

The Public Health Agency of Canada’s National Microbiology Laboratory (NML) is Canada’s leading public health infectious disease laboratory. It offers the world’s highest level of containment. It’s also a place where scientists conduct research on bacteria and viruses in order to advance science and technology and to help protect Canadians and the public.

Launched on May 10, 2002, as part of the federal government’s security agenda, the Chemical, Biological, Radiological-Nuclear and Explosives (CBRNE) Research and Technology Initiative (CRTI) began as a $170-million, five-year initiative, managed by Defense Research and Development Canada. Since then, it has proven to be an extremely effective model for bringing together Canada’s national science and technology (S&T) and security communities and applying their collective knowledge and capabilities towards common goals.

Bioterrorism is an issue of public concern that falls under the NML umbrella. The mandate of the division is to support diagnostic detection activities for emerging bacterial pathogens originating naturally or from bioterrorism. Through collaborative and coordinated efforts, the NML is working to enhance Canada’s capability and capacity to respond to this issue, while CRTI is rapidly funding the gaps in the hopes of addressing Canada’s preparedness.

This month Biotechnology Focus goes one on one with the chief, Emerging Bacterial Pathogens Division National Microbiology Laboratory Public Health Agency of Canada, Dr. Jody Berry, who was part of an NML team that headed project CRTI 03-0021TD (3).

The project, which was completed in 2007, involved the development of a number of immuno assays for detecting bioterrorist agents. Most were based on antibody antigen interaction. Berry explains the project and how its goal is to enhance Canada’s capacity to deal with potential chemical and biological threats to public security.

Q: According to the project description, the goal of this project was to develop immunodiagnostic assays capable of detecting human, animal and zoonotic biothreat agents. Can you elaborate further?

A: We wanted to create some sort of standardized assay capable of rapid detection and identification. At that time each of our agencies came up with what would be the most important biological threat for us to develop rapid assays for. And having said that, at that time there were already tests for these agents, but the tests were not as modern as we needed them to be, not as rapid and not as standardized across the board. So we went to work in 2003 to build upon what we had, and to address these shortcomings.

Q: What biothreats were targeted?

A: The priority list was set by CRTI, which has a similar threat level list to CDC (U.S. Centers for Disease Control). Anthrax was a big one on the list and we’re happy to say that it is not a worry anymore. There were other toxins that were on the list too, some animal pathogens and some other zoonotic agents that the military was interested in and we knocked off all of those ones that were of the highest priority.

Q: Were the goals of the project realized? What was the impact of the project?

A: The goals of the project were realized. We patented some of the reagents that came out of these projects but we haven’t patented the assays. The whole point to this was the Canadian Government needed to be able to keep the reagents in house because of the events of 2001 showed us that when the U.S. or the U.K. is in trouble, we can’t just open a catalogue and phone them and try and buy this technology because they’re busy using it themselves. So it was a very abrupt realization that we needed to be able to guarantee our own tests and have these types of specialized reagents. We distribute these reagents to our partners and allies, through the U.S. critical reagent program and to the UK as well, but mostly they for our own use. As such, the development and production of Canadian assays will ensure the national availability of high-quality reagents to the Canadian first responder and health care communities at times of critical need, without the need to procure these reagents from foreign sources.

Q: What makes these assays unique?

A: Almost all of these assays were immunological assays, so they were based on the development of immunological reagent antibodies that directly detect the pathogen. A lot of modern assays use things like PCR, which is a nucleic acid amplification that will show the presence of an agent whether it’s alive or dead. But in this case that wasn’t good enough because it doesn’t work on toxins for example, or proteins. Antibodies though can recognize toxins directly and show whether they’re there or not and fulfills the ability to have independant test methods to confirm or disprove an event.

Q: How do the assays work?

A: Almost all them work by using antibodies, which are proteins that your immune system makes that detect by binding to the pathogen or its product like a toxin. Monoclonal antibodies are antibodies produced by a single cell that we derive from animals or through recombinant methods. So its one cell producing one antibody with one specificity and we through our testing determine the level of reactivity, sensitivity and conclude beyond a shadow of a doubt whether there is something or isn’t something in the sample. Basically the method involves coating a plate or some kind of bead with the antibody, running the unknown sample over it and then we use a second antibody to detect the presence of a pathogen. It can all be done depending on the test within an hour or couple of hour’s time frame.

Q: Who backed this project?

A: For this project we had multiple federal agencies, ourselves, the Canadian Food Inspection Agency’s, National Centre for Foreign Animal Disease and The Defense Research Development group (DRDC, the department that manages the CRTI program) to name a few. The idea behind the project was you had to have two federal agencies on board showing synergy in order to get funded.

Q: What is the CRTI and what was its relationship to this project?

A: CRTI was originally a funding body that was set up to rapidly fund areas that were determined to be gaps in Canada’s preparedness, in particular in response to the events that happened in the United States in 2001, and the letter incidents with Anthrax. Rather than fund individual agencies and departments and wait for a trickle down effect in each one of those departments, it was decided that the best course of action was to create a granting agency where scientists could be funded directly at the bench. CRTI was the result and it has developed into a very unique granting agency since its creation.

Q: Has CRTI gone forward with any other projects as a result of the success of this project?

A: The agencies involved have ramped up their own programs to continue on with these projects and keep the reagents involved in the assays functional. However, there are also plans for future extensions or adapt to’s from this project. In fact DRDC Suffield submitted an application for an extension of the project and hopefully that will get funded. There’s also direct links to other programs and departments, as well as other projects at NML.

Q: What else are you working on right now in terms of your work with the National Microbiology Laboratory?

A: We work on all kinds of public health threats. Obviously pandemic influenza is a big concern these days and just about any other common bug that’s a threat to Canadians. My group is mainly involved in immuno assays, usually direct detection, but we also do some nucleic acid work. We use a variety of technologies and we’re getting into the micro-array and nano-sensor type technology. We’re kind of always trying to stay on the cutting edge of technologies that are presented out there by companies or other institutes across the US and Europe.

Q: Is biodefence still a priority for Canadian Science and Technology?

A: I think it is. I think that the biggest benefit of projects such as these and other biodefence work is that everything we’ve done, learned, produced and the groups we’ve built are not only used for being prepared, but they’re also being used for public health. Preparedness for a biological event is the same for bioterrorism as it is for a natural outbreak. And we’re quite well prepared now.

Q: Where do you want to see the work go from here?

A: I hope CRTI continues to be interested in this type of work. And I would like to see this work and our research in particular turn into real therapeutic opportunities for not only Canadians, but also human beings in general.

Dr. Jody Berry is Chief, Emerging Bacterial Pathogens Division National Microbiology Laboratory, Public Health Agency of Canada.