Scientists at the National Institutes of Health (NIH) are getting closer to preventing the spread of HIV or human immunodeficiency virus.
Researchers at the NIH's National Institute of Allergies and Infectious Diseases (NIAID) have successfully identified an antibody from an HIV-infected patient that potently neutralized 98 percent of HIV strains, including 16 of 20 strains that are resistant to other antibodies of the same class.
The antibody, named N6, could be further developed to potentially treat or prevent HIV transmission, the researchers said.
According to research leader Mark Connors, M.D. of NIAID, the team observed the evolution of N6 over time to find out how it could potently neutralize nearly all HIV strains. By understanding this process, scientists hope to create vaccines that could help protect people from acquiring the virus.
Identifying neutralizing antibodies had been challenging, as the virus is capable of rapidly changing its surface proteins to hide from the immune system. In 2010, scientists at NIAID's Vaccine Research Center (VRC) discovered an antibody called VRC01 that is capable of stopping up to 90 percent of HIV strains. Researchers from the California Institute of Technology conducted experiments on mice and found that mice with the neutralizing antibody VRC01 were infected by the virus but did not develop HIV disease.
N6 works in the same way as VRC01, where it binds to a part of the HIV envelope called CD4 binding site, preventing the virus from attaching to the immune cells. But N6 evolved a unique mode of binding, allowing it tolerate changes in the HIV envelope, including the attachment of sugars in the V5 region of the envelope. This means N6 could provide a greater level of protection than VRC01-class antibodies.
Due to its potency, N6 could also offer stronger and more durable prevention and treatment benefits, and researchers could administer it subcutaneously (into the fatty layer under the skin), rather than intravenously like VRC01.
In the United States alone, over 1.2 million people are living with HIV/AIDS, the Centers for Disease Control and Prevention (CDC) said.