Waterloo researchers working on new way to prevent HIV infection in women

University of Waterloo researchers are working on a new way to prevent women from becoming infected with HIV.

Implant uses FDA-approved drug to modulate body’s immune response, professor says

After years of research, professor Emmanuel Ho and his team, have finished an initial phase of testing for an implant that uses the body’s own immune cells to reduce the chances of HIV infection. (University of Waterloo)

University of Waterloo researchers are working on a new way to prevent women from becoming infected with HIV.

After years of research, professor Emmanuel Ho and his team have finished an initial phase of testing for an implant that uses the body's own immune cells to reduce the chances of infection.

Ho said current HIV-prevention strategies include condoms and anti-HIV drugs, which "eliminate HIV that's already infected the cells."

But, he said, there are major issues with access to condoms and anti-HIV drugs in developing countries.

"Due to socio-cultural factors, they're not able to negotiate condom usage, for example, with their sexual partners or they may not have access to condom usage," he said. "If women want to be able to protect themselves, knowing that they're at high-risk of being infected with HIV, they're not allowed to be able to have control and use condoms."

'Resting' T-cells

So Ho and his team of researchers looked at sex workers in Kenya, some of which, he said, have a natural immunity to HIV.

"No matter how much they're exposed to HIV-infected clients for example, they don't become infected with HIV. Upon analysis, it looks like the T-cells, or the immune cells in their body, they're in a state of what's called immune-quiescence. They're kind of resting," he said, adding those are the cells HIV targets for infection.

The team hopes to replicate that "resting" of T-cells in other people, particularly women, to prevent HIV infection.

They're using a small, vaginal implant to deliver a drug called hydroxychloroquine. It's FDA-approved, widely used for treatment of rheumatoid arthritis and malaria, and is cheap to produce.

"The main finding for us, was our ability to actually deliver a very common drug to actually modulate the human immune system to potentially prevent HIV infection," he said.

"No one has ever kind of shown that we can actually use a drug to create this immune-quiescence state."

Discrete, long-term method of protection

The team is specifically looking at implants, Ho said, because it allows women to not think about having to protect themselves in the moment. Instead, it's a discrete, long-term method of protecting themselves.

The implant has a hollow tube and two pliable arms to hold it in place. The drug is released through the tube slowly and is absorbed directly.

The team found T-cell activation was significantly reduced in animals.

He said the next step is looking at whether or not the team can actually prevent HIV in a "more appropriate model."

"I think this is a really big deal actually," Ho said. "It adds another realm of potential strategy for preventing HIV."

The next phase of research will begin soon, and the team hopes to eventually apply the research to men, as well.

The implant has a hollow tube and two pliable arms to hold it in place. The drug is slowly released through the tube. (University of Waterloo)