A team of researchers in the Division of Infectious Diseases at the University of North Carolina School of Medicine recently found that human immunodeficiency virus (HIV) infections target tissue macrophages, which are large white blood cells located in the brain, liver and connective tissues.
When the virus has successfully targeted these macrophages, it reproduces and infects itself so that it can spread throughout the body. The purpose of macrophages is to absorb foreign material, such as CD4 T cells that are infected.
This discovery contradicts several earlier studies that questioned the role and importance of these macrophages; previous research decided that macrophages were not used until they absorbed infected CD4 T cells.
The researchers studied HIV within novel small animal models, which do not have T cells to support the HIV. They discovered the HIV used the macrophages to create macrophage-tropic HIV strains. This allows the virus to replicate itself within these crucial cells.
"If the T cells were the only target of HIV cure research, eradicating the virus would still be tough," Dr. J. Victor Garcia, study co-author and a professor of medicine in the Division of Infectious Diseases at UNC, said. "Now we have demonstrated that there is another cell target where replicating HIV can be found, which could make eradicating the virus from the host and finding a cure for HIV/AIDS harder."
The results are available in the Journal of Clinical Investigation.
"This model will allow us to ask the critical question as to whether or not macrophages represent a latent reservoir for HIV after treatment with antiretroviral therapy," Dr. Jenna Bone Honeycutt, lead author of the study and a postdoctoral fellow in the Division of Infectious Diseases at UNC, said. "These experiments will inform the future direction of HIV cure research as we know it."