Zack, J. A. | bioRxiv Science

bioRxiv2026

Modeling HIV infection, treatment, rebound, and intervention in human immune organoids

Targeting the HIV-infected reservoir in lymphoid tissues (LT) will be critical to developing a cure for people living with HIV (PLWH). LT explants used to study HIV infection enable the evaluation of human-specific disease progression and treatment response; however, their short lifespan makes it challenging to assess long-term treatment interventions. We therefore established an immune organoid model of HIV infection using human tonsil or spleen cells, demonstrating productive HIV infection and viral integration into CD4+ T cells. Treatment with a protease inhibitor fully suppressed ongoing viral production, with virologic rebound occurring within days of treatment interruption. The transfer of healthy allogeneic NK cells to target the reservoir upon treatment interruption reduced the number of infected cells, intact viral genomes, and production of de novo infectious viral particles. Adoption of this immune organoid platform will accelerate the evaluation of cure-based strategies to eliminate the HIV reservoir in tissues for PLWH.

immunology↗

bioRxiv2026

NK Cells Engineered with a Chimeric Antigen Receptor Delay HIV Rebound and Reshape HIV Reservoir Composition

Durable HIV remission will require strategies that eliminate or permanently silence the latent reservoir that persists despite antiretroviral therapy (ART). Natural killer (NK) cells possess inherent antiviral activity, but unmodified NK cells have limited ability to recognize or clear latently infected cells during ART suppression. We engineered allogeneic human primary NK cells expressing a truncated CD4-based chimeric antigen receptor (D1D2-CAR) that targets the conserved CD4 binding site on HIV Env without permitting viral entry, and evaluated their activities in humanized mice infected with barcoded CCR5-tropic HIV. D1D2-CAR NK cells selectively killed HIV-infected primary CD4 T cells in vitro and significantly delayed viral rebound following ART interruption in humanized mice compared to GFP-NK or no NK control groups. Barcoded HIV tracking showed that CAR-NK treatment reduced the number, diversity, and inter-organ overlap of rebounding viral RNA and proviral DNA lineages, yielding rebound driven by a restricted set of dominant clones. Integration site and chromatin analysis further demonstrated selective depletion of proviruses positioned in genes, enhancers, promoters, and open chromatin. These findings show that CAR-NK cells can target rare reactivation events during ART suppression and reshape the reservoir toward a less rebound-competent, epigenetically repressive state.

immunology↗