HIV stands for human immunodeficiency virus which attacks the body’s immune system and destroys certain T cells called CD4+ which is one of the important immune cells of the body.
In a University of Waterloo, scientists have developed a new tool which is a vaginal implant to protect women from HIV infection. Unlike other methods of HIV prevention like anti-HIV drugs or condoms, this vaginal implant tool uses people’s natural immunity to fight against the virus. It helps in decreasing the number of cells which can be targeted by the virus to cause infection in women genital tract. This article recently got published in the Journal of Controlled Release.
When a virus enters into the person’s body, it starts infecting CD4+ cells which are mobilized by the immune system in response to virus invasion. When the T cells become immobilized and do not fight the virus they are not infected and the HIV virus is not transmitted between people. This resting stage of T cells is referred as immune quiescent.
“We know that some drugs are taken orally never make it to the vaginal tract, so this implant could provide a more reliable way to encourage T cells not to respond to infection and therefore more reliable and cheaply prevent transmission,” said Emmanuel Ho, a professor in the School of Pharmacy at Waterloo. “What we don’t know yet is if this can be a stand-alone option for preventing HIV transmission or if it might be best used in conjunction with other prevention strategies. We aim to answer these questions with future research.”
Ho and research partner Keith Fowke of the University of Manitoba, observed that in Kenya many of sex workers women who had sex with HIV positive clients were not contracting the virus. After doing some study, they found that these women possessed T cells that were naturally immune quiescent.
“Observing this, we asked ourselves if it was possible to pharmacologically induce immune quiescence with medication that was better assured of reaching the point of infection,” said Ho. “By delivering the medication exactly where it’s needed, we hoped to increase the chances of inducing immune quiescence.”
This vaginal implant tool is made up of a hollow tube with two pliable arms holding it in its place. It contains hydroxychloroquine (HCQ) which is disseminated slowly through the porous material of the tube and absorbed by the walls of the vaginal tract.
Researchers tested the implant in the animal model and found that T cell activation was reduced by a large number, which means that vaginal tract was showing an immune quiescent state.