McMaster researchers take steps towards developing chlamydia vaccine

Researchers at McMaster University are one step closer to developing a preventative vaccine against chlamydia.

Current trials in mice show great promise in preventing the spread of the bacteria

Chlamydia flyer at a sexually health clinic. (CBC)

Researchers at McMaster University are one step closer to developing a preventative vaccine against chlamydia.

Jim Mahoney, a professor of pathology and molecular medicine at McMaster, is one of the lead researchers at the Michael G. DeGroote Institute for Infectious Disease Research. He said his team has developed an experimental vaccine that is being used to treat chlamydia in mice, and so far, it's been very successful.

In a study, recently published in the journal Vaccine, the researchers describe a novel chlamydial antigen — known as BD584 — that is a potential vaccine candidate for the most common species of chlamydia.

Chlamydia is a common sexually transmitted Infection (STI) that impacts 131 million people around the world each year. 

Many infections are left untreated

Hamilton researchers are taking the first steps towards developing a vaccine for chlamydia. (CBC)

Around 70 per cent of chlamydia infections are asymptomatic, Mahoney said. This means seven out of 10 women with chlamydia won't know they're infected and the bacteria will likely go untreated. This could lead to upper genital tract infections or damage to fallopian tubes, causing infertility, he said.

"Our vaccine reduces the amount of bacterial replication in the lower tract and prevents it from getting into the upper tract and prevents it from causing fallopian tube damage," he said.

Ten years ago, Mahoney said, his small team of researchers received funding — roughly $250,000 — from the Canadian Institutes for Health Research. Over the last few years, they received another $160,000 from the CIHR, as well as various smaller grants to fund their research. 

'Human trials in two to three years'

Mahoney said chlamydia uses a secretion system to spread and infect cells. The team has identified three key proteins in that system that are pivotal in its operation and targeted them as candidates for the vaccine.

"If you knock out the secretion system, it cannot infect cells," he said. 

So far, trials in mice have shown to be 90 per cent effective in decreasing bacterial replication the rodent test subjects. Later this year, Mahoney said his team plans to move ahead with trials in larger animals like guinea pigs.

If the trials continue to be successful, the vaccine will be used in non-human primates. Tests on these animals are required before anything is tested on humans.

"If everything goes well, we could be in phase one of human trials in two to three years," he said. 

'This is only the first step'

The vaccine will be administered through the nose, Mahoney said. This makes it an inexpensive solution for developing nations and won't require highly trained health professionals to administer it.

Since the research was published, the team has been getting some attention from American vaccine companies who are interested in supporting the research. Mahoney said his team will likely work with these companies and continue the research with their funding.

Even if the human trials are successful, it will still be years before it becomes publicly available, he said.

"It's a long process … This is only the first step." 

Chris Seto | @topherseto


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