CD32+CD4+memory T cells are enriched for total HIV-1 DNA in tissues from humanized mice

Summary CD32 has raised conflicting results as a putative marker of the HIV-1 reservoir. We measured CD32 expression in tissues from viremic and virally suppressed humanized mice treated relatively early or late after HIV-1 infection with combined-antiretroviral therapy. CD32 was expressed in a small fraction of the memory CD4+ T cells subsets from different tissues in viremic and aviremic mice regardless of treatment initiation time. CD32+ memory CD4 + T cells were enriched in cell-associated-(CA) HIV-1 DNA but not in CA-HIV-1 RNA as compared to the CD32-CD4+ fraction. Using multidimensional-reduction analysis several memory CD4+CD32+ T cell clusters were identified expressing HLA-DR, TIGIT or PD-1. Importantly, although tissues resident CD32+CD4+ memory cells were enriched with translation-competent reservoirs, most of it was detected in memory CD32- CD4+ T cells. Our findings support that CD32 labels highly activated/exhausted memory CD4+T cell subsets that contain only a small proportion of the translation-competent reservoir.