Adoptive Transfer of Haploidentical NK Cells and N-803

Human immunodeficiency virus (HIV) infection causes profound and often irreversible changes to the adaptive and innate immune system. In the absence of antiretroviral therapy (ART), Cluster of Differentiation (CD)4+ T cells are progressively depleted, CD8+ T cells are often expanded, and much of the immune system is chronically activated. Much of these abnormalities improve during long-term ART, but the system rarely returns to normal. Notably, chronic inflammation persists indefinitely during ART, and is driven by multiple factors, including HIV production (and perhaps replication), irreversible loss of the mucosal integrity and exposure to gut microbes, and an excess burden of other pathogens such as cytomegalovirus (CMV). How the virus and its host interact during effective ART is the focus of intense investigation. HIV-1 preferentially infects activated memory CD4+ T cells that express the chemokine receptor CCR5, although resting CD4+ T cells, naïve CD4+ T cells and macrophages can also be infected. The majority of infected and activated CD4+ T cells die quickly, but a small fraction reverts to a resting state and persistent indefinitely as the latent reservoir. Because ART blocks all or nearly all new infection events, the reservoir that exists at the time ART is initiated becomes the reservoir that persists for the life of the individual. This memory T cell viral reservoir is maintained during ART by the long half-life of the infected cell, homeostatic proliferation of these cells and perhaps by low levels of persistent viral replication. The viral reservoir in peripheral blood exists predominantly in those longer-lived memory CD4+ cells endowed with regenerative potential, including memory stem cells, central memory cells and transitional memory. The reservoir also persists in potentially shorter-lived CD4+ T effector cell populations, but whether these cells represent a stable reservoir or one that is constantly being regenerated via proliferation and differentiation is unknown. "Shock and Kill". One approach to curing HIV infection that has generated broad support in the field is to induce latently infected cells to produce virus (the "shock") while enhancing the ability of the host to clear these virus-producing cells (the "kill"). Histone deacetylase (HDAC) inhibitors have been shown to increase production of HIV-1 RNA and to a lesser degree virus particles from the viral reservoir in vivo. The magnitude of the effect of HDAC inhibitors is modest at best, and as of yet this class of drugs has had no consistent effect on the frequency of cells that harbor replication-competent HIV. Other classes of anti-latency drugs and immunomodulators are therefore being explored for their capacity to stimulate the viral reservoir. To augment the capacity of the host to eliminate reservoir cells following activation, several immunologic strategies are being explored. These strategies include therapeutic vaccines, monoclonal antibodies, and immune checkpoint inhibitors.