18 April 2018

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."

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."

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.

Read the full article online here.