Brain cells can harbor HIV

Brain cells can harbor and spread the HIV virus to the body

Astrocytes, a type of brain cell that can harbor HIV and afterward spread the virus to immune cells that traffic out of the brain as well as into other organs was discovered by the scientists at Rush University Medical Center, Chicago. Even when the virus was suppressed by a typical treatment for HIV – combination antiretroviral treatment (cART), HIV moved from the brain using this route. The study is published in the journal PLOS Pathogens.

Jeymohan Joseph, Ph.D., chief of the HIV Neuropathogenesis, Genetics, and Therapeutics Branch at NIH’s National Institute of Mental Health said, “This research demonstrates the vital duty of the brain as a reservoir of HIV that can re-infect the peripheral body organs with the virus”. “The research suggests that treatment strategies need to address the role of the central nervous system in order to get rid of HIV from the body”.

The immune system is attacked by HIV by infecting CD4+ (CD4 positive) T cells, a type of WBC that is essential to combating off the virus. HIV can destroy CD4+ T cells if treatment is not provided, reducing the body’s ability to mount

an immune reaction – leading to AIDS.

Combination antiretroviral treatment, which effectively subdues HIV infections, has benefited lots of people with HIV to live much longer – much healthier lives. However, numerous people receiving antiretroviral medicines additionally show signs of HIV-associated neurocognitive disorders, such as thinking and memory issues as per some studies. Scientists know that HIV enters the brain within 8 days of infection, yet less is understood about whether HIV-infected brain cells can release viruses that can move from the brain back into the body to infect other tissues.

A variety of tasks – from maintaining the blood-brain barrier to supporting communication between brain cells is carried out by the billions of astrocytes present in the brain. HIV-infected or noninfected human astrocytes were transplanted into the brains of immunodeficient mice to study whether HIV can relocate from the brain to peripheral body organs by Lena Al-Harthi, Ph.D., and her research team at Rush University Medical Center.

The transplanted HIV-infected astrocytes were able to spread the virus to CD4+ T cells in the brain. Later, spreading out the infection to peripheral organs such as the lymph nodes and spleen, these CD4+ T cells moved from the brain into the rest of the body. Additionally, they found that when animals were provided cART, HIV egress from the brain took place, albeit at reduced levels. Showing a rebound of the viral infection – HIV DNA/RNA became observable in the spleen – when cART therapy was disrupted.

Dr. Al-Harthi said, “The research describes that HIV in the mind is not trapped in the brain it can and also moves back into peripheral organs with leukocyte trafficking”. “It also explained the function of astrocytes – even under cART treatment, in supporting HIV replication in the brain”.

Dr. Al-Harthi said, “This data has considerable implications for HIV cure methods, thus strategies need to be able to properly target and also remove reservoirs of HIV replication and reinfection”.

May Wong, Ph.D., program director, the NeuroAIDS, and Infectious Diseases in the Neuroenvironment at the NIH’s National Institute of Neurological Disorders and Stroke, said “Effecting 30-40 million people around the world, HIV continues to be a major international public health concern. We require to fully know how HIV affects the brain and also various other tissue-based reservoirs to help the patients”. “This research brings us one more step closer and further studies that reproduce these findings are required”.

The research was funded by the National Institutes of Health and co-funded by NIH’s National Institute of Mental Health and National Institute of Neurological Disorders and Stroke.

Author: Sruthi S