A new study published June 16 in the Journal of Clinical Investigations, found that microglial cells, specialized immune cells with a long lifespan in the brain, can serve as a stable viral reservoir for latent HIV.
As a part of its life cycle, the human immunodeficiency virus-1 (HIV) inserts a copy of its DNA into human immune cells. Some of these newly infected immune cells can then transition into a dormant, latent state for a long period of time.
Although current therapies, such current antiretroviral therapy (ART), can successfully block the virus from replicating further, it cannot eradicate latent HIV. If treatment is ever discontinued, the virus can rebound from latency and reignite the progression of HIV infection to AIDS.
In the new study, led by scientists from the University of North Carolina’s School of Medicine, it has been confirmed that microglial cells can serve as a stable viral reservoir for latent HIV. The team studied the brains of macaques with the simian immunodeficiency virus (SIV), a virus that is closely related to HIV, to get a better understanding of how to extract and purify viable cells from primate brain tissue.
Researchers used physical separation techniques and antibodies to selectively remove microglial cells. Using these techniques, researchers then obtained samples that were donated by HIV+ people who were enrolled in “The Last Gift” Study at the University of California San Diego (UCSD).
The study involved altruistic HIV+ people, who are taking ART but suffering from other terminal illnesses, will their bodies to further the HIV research project. Now that the researchers know that latent HIV can take refuge in microglial cells in the brain, they are considering plans to target this type of reservoir.
“Since latent HIV in the brain is radically different from the virus in the periphery, researchers believe that it has adapted special characteristics to replicate in the brain,” explained first author Yuyang Tang, assistant professor of medicine in the Division of Infectious Diseases at UNC.
