Latent HIV-1 Infection of Resting CD4+ T Cells in the Humanized Rag2-/- γc-/- Mouse

Persistent human immunodeficiency virus type 1 (HIV-1) infection of resting CD4(+) T cells, unaffected by antiretroviral therapy (ART), provides a long-lived reservoir of HIV infection. Therapies that target this viral reservoir are needed to eradicate HIV-1 infection. A small-animal model that recapitulates HIV-1 latency in resting CD4(+) T cells may accelerate drug discovery and allow the rational design of nonhuman primate (NHP) or human studies. We report that in humanized Rag2(-/-) gamma(-/-)(c) (hu-Rag2(-/-) gamma(-/-)(c)) mice, as in humans, resting CD4(+) T cell infection (RCI) can be quantitated in pooled samples of circulating cells and tissue reservoirs (e. g., lymph node, spleen, bone marrow) following HIV-1 infection with the CCR5-tropic JR-CSF strain and suppression of viremia by ART. Replication-competent virus was recovered from pooled resting CD4(+) T cells in 7 of 16 mice, with a median frequency of 8 (range, 2 to 12) infected cells per million T cells, demonstrating that HIV-1 infection can persist despite ART in the resting CD4(+) T cell reservoir of hu-Rag2(-/-) gamma(-/-)(c) mice. This model will allow rapid preliminary assessments of novel eradication approaches and combinatorial strategies that may be challenging to perform in the NHP model or in humans, as well as a rigorous analysis of the effect of these interventions in specific anatomical compartments.