Researchers may have discovered where in the body HIV takes refuge during antiretroviral treatment

Québec City, December 2, 2019—An international team led by Professor Jérôme Estaquier from Université Laval's Faculty of Medicine and the CHU de Québec-Université Laval Research Center may have discovered where in the body HIV takes refuge during antiretroviral treatment. Research conducted using an animal model indicates that the virus may hide in lymph nodes in the spleen and gut. The researchers believe those lymph nodes are the staging ground from which the virus prepares to relaunch the infection after treatment has stopped, according to the study published in Mucosal Immunology from publisher Nature Research.

The researchers conducted their research using macaques infected with simian immunodeficiency virus (SIV), a close cousin of HIV. They found that during antiretroviral treatment, two types of cells in the spleen and gut lymph nodes serve as reservoirs replication sites for the virus. These cells belong to the family of CD4 T lymphocytes, the preferred target of HIV.  

«These cells are involved in mounting the immune response,» said Professor Estaquier. «We don't know why the viruses taking refuge in these cells are able to escape antiretroviral drugs. They may have a mechanism that limits the flow of drugs or eliminates them faster. To improve treatment, we'll need a better understanding of what allows these cell populations to escape antiretroviral drugs.»

For the purposes of the study, the researchers focused on the tissues and lymph nodes that harbour CD4 T cells. Other organs of the body that are not linked to the lymph system may also serve as reservoirs for HIV. Professor Estaquier's team is pursuing its research, with more results expected in the coming months.

If the results obtained with SIV can be confirmed with HIV in humans, they would bring us one step closer to a cure for AIDS. «Finding the cells and anatomical sites where HIV takes refuge and destroying them are the main obstacles to developing therapies to cure AIDS,» said Professor Estaquier.