Genetically engineered human antibodies that bind to two targets on HIV could one day be used to treat and prevent the disease.
'Broadly neutralizing' antibodies can block various HIV strains, but the virus can overcome them by changing the viral protein that the antibodies recognize. To combat this viral escape, a team led by Jeffrey Ravetch at the Rockefeller University in New York City developed HIV antibodies that can recognize two different spots on the envelope protein that adorns the virus. One of these bispecific antibodies lowered viral levels in HIV-infected mice by more than tenfold in comparison with broadly neutralizing antibodies.
An independent team led by David Ho, also at the Rockefeller University, created bispecific antibodies that recognize both the HIV envelope protein and human proteins that HIV uses to infect immune cells. The most potent of these antibodies protected mice from becoming infected with HIV and decreased viral levels in those already infected.