Illustration of how the engineered protein facilitates destruction of latently
HIV-infected immune cells.
1) Protein and cells, from left to right: engineered protein with yellow-and-black
CD3-binding end and thick black HIV-binding end; latently HIV-infected helper
T cell (blue); inactivated killer T cell (red).
2) Protein binds to CD3 receptor on helper T cell, activating it so the helper
T cell starts making HIV and displaying pieces of virus (red) on its surface.
3) Protein binds to HIV fragment on helper T cell and CD3 receptor on killer T cell,
activating the killer T cell and bringing the two cells close together.
4) Activated killer T cell destroys HIV-infected helper T cell.
(October 21, 2015) WHAT: Scientists at the National Institutes of Health (NIH) have created a protein that awakens resting immune cells infected with HIV and facilitates their destruction in laboratory studies. The protein potentially could contribute to a cure for HIV infection by helping deplete the reservoir of long-lived, latently HIV-infected cells that can start making the virus when a person stops taking anti-HIV drugs. Further studies in animals and people are needed to determine the viability of this approach.
The researchers found that the protein, called VRC07-αCD3, triggered the activation and killing of latently HIV-infected helper T cells taken from patients on antiretroviral therapy when the cells were incubated in the lab with the patients’ own killer T cells. In addition, the scientists found a monkey-adapted version of the protein to be safe and well-tolerated when given to monkeys infected with a simian form of HIV and receiving antiretroviral therapy. The researchers are now studying the effectiveness of monkey-adapted VRC07-αCD3 in the animals.