Broadly neutralizing antibodies (bNAbs) such as PGDM1400 show promise as prophylactic and therapeutic agents against HIV-1. Human immune system mice were passively immunized with different doses of PGDM1400 and challenged 24 h later with a high dose of HIV-1JRCSF. We found that PGDM1400 provided protection against HIV-1 challenge in a concentration dependent manner and that the protective concentration in blood was ∼75-fold higher than the in vitro 50% inhibitory concentration. The results demonstrate that PGDM1400 might be a promising component of strategies to prevent HIV-1 infection and provide support for the pursuit of vaccines that induce PGDM1400-like bNAbs.
Keywords: HIV-1; PGDM1400; broadly neutralizing antibody; human immune system mouse; prophylactic agent.