Cancer-killing virus tried in pet cats moves to human trials

Scientists at Ontario Veterinary College (OVC) at the University of Guelph have discovered that injecting a cancer-killing virus into the spleens of cats who have developed cancer boosts the animals’ immune response to the disease. They believe the discovery--of both the virus and the delivery mode--can be applied to many types of cancer in people, including breast cancer, leukemia and prostate cancer.

The researchers are working with an engineered form of the bug rhabdovirus, they reported in the Journal of Immunology. Injecting the virus into the spleen, they wrote, led to a rapid proliferation of memory T cells--an immune response that helps the body fight off cancer on its own. The researchers believe that the delivery method also negates the need to wait for the immune response to die down and then give a booster vaccine.

“By getting the vaccine to this unique location in the body, we were able to get an unprecedented immune response in minimal time,” said Byram Bridle, the lead researcher on the project, in a press release. “What injecting the viruses into the spleen does is it allows us to bypass the regulatory mechanism that would limit its effectiveness. When we conducted these tests in animals, we saw high success rates in treatment of cancer.”

The trials were conducted on cats suffering from cancer that were brought to Ontario Veterinary College for treatment, according to the release. The clinic expects to try the same therapy on dogs with cancer in the next year. Clinical trials in people are also set to begin in Ottawa, Hamilton and Toronto.

Conducting trials of experimental therapies in pets with cancer, a field known as comparative oncology, has been gaining steam in recent years. Last summer, the National Academies' Institute of Medicine hosted a conference on the topic in Washington, D.C., which included input from several universities and companies that are leading comparative research efforts, such as Yale University, Colorado State University and Gilead ($GILD).

Comparative oncology is part of a larger initiative known as One Health, which encourages research collaborations between veterinarians and scientists studying diseases that cross species. Earlier this month, the USDA set up a web portal focused on diseases that the agency feels require a One Health approach to conquering, including avian and swine flu.

Bridle believes his cancer study could be applied to the effort to combat other diseases, such as dengue fever and Ebola. He says connecting scientists from different fields will be key to advancing the research. “We are living in a world where diseases seem to be growing faster than treatment, so we need to outpace them,” he said in the release.

- here’s the press release
- get the Journal of Immunology study here

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