Tropes

R_www.biologynews.net_ 2015 00260.txt.txt

#HIV cure research: NIH scientists create 2-headed protein to deplete HIV reservoir 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-acd3 triggered the activation and killing of latently HIV-infected helper T cells when the cells were taken from patients on antiretroviral therapy and then 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-acd3 in the animals. The engineered protein has two ends: one activates T cells by binding to a surface molecule called the CD3 receptor, and the other--based on an antibody called VRC07--powerfully binds to more than 90 percent of HIV strains. VRC07-acd3 facilitates the killing of latently HIV-infected cells in three steps. First, the CD3-binding end attaches to a resting, HIV-infected helper T cell, activating the cell so it starts making HIV and displaying pieces of virus on its surface. Next, the HIV-binding end of the protein latches onto those pieces of virus while the CD3-binding end attaches to a killer T cell, activating it and bringing it close to the helper T cell. Finally, the activated killer T cell destroys the HIV-infected helper T cell. A team of scientists at the Vaccine Research center (VRC) of the National Institute of Allergy and Infectious diseases, part of NIH, created VRC07-acd3 under the leadership of VRC Director John R. Mascola, M d.;former VRC Director Gary J. Nabel, M d.,Ph d.;and Richard A. Koup, M d.,VRC deputy director and chief of its immunology laboratory a

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