Blockade of type I interferon signaling reverses HIV-1 induced immune dysfunction and reduces HW-1 reservoirs

Abstract Type I interferons (IFN-I) are critical for controlling virus infections, but they also contribute to impaired host immunity and virus persistence. Although IFN-I inhibit HIV-1 replication in vitro and in vivo, persistent IFN-I induction is correlated with immune dysfunction and disease progression in HIV-1 infected patients and in SIV infected monkeys. Moreover, despite efficient suppression of HIV-1 replication with combined antiretroviral therapy (cART), low levels of IFN-I signaling persist in some individuals, which may impede immune recovery and foster viral persistence. We report here studies using a monoclonal antibody to block IFN-α/β receptor (α-IFNAR) signaling in humanized mice (hu-mice) persistently infected with HIV-1. We found that IFNAR blockade rescued human T cells both in number and function despite elevated HIV-1 replication. We further discovered that, in HIV-1-infected mice treated with cART, blocking IFNAR fully reversed HIV-1-induced immune hyper-activation and rescued anti-HIV-1 immune responses. Finally, IFNAR blockade in the presence of cART reduced the size of HIV-1 reservoirs in lymphoid tissues and delayed HIV-1 rebound post-cART cessation. Our results suggest that blocking IFNAR may provide a novel approach to enhance immune recovery and to reduce HIV-1 reservoirs in those who sustain elevated IFN-I signaling during suppressive cART.