Targeted Bacteriophage T4 Nanoparticles Reverse HIV-1 Latency in CD4+ Human T Cells

A major barrier for HIV-1 eradication is the latent virus reservoir containing stably integrated and silent proviruses in CD4+ T-cells. Targeted reactivation and removal of this latent reservoir is a potential strategy for HIV-1 cure but remains a major challenge. Here, we investigated whether CD4-targeted bacteriophage T4 capsid nanoparticles that mimic HIV envelope can reactivate HIV-1 latency. The nanoparticles were arrayed with CD4-binding CD4-DARPin, or HIV-1 gp140 envelope trimer. When exposed to J-Lat T-cell model of HIV-1 latency or primary T-lymphocytes from human PBMCs, these nanoparticles activated CD4+ T-cells without causing global T-cell activation, which led to activation of HIV-1 proviral transcription, viral protein production and release. Intriguingly, the observed T-cell activation and HIV-1 latency reversal do not involve the classic PKC or NFAT pathways and did not lead to cytokine storm. These studies indicate that engineered non-infectious bacteriophages can be exploited for HIV-1 cure and targeted T-cell therapies.