Figure 1. Interactions between HIV-infected cells of different maturational phenotypes and CTLs from participants on ART.

Viral latency is a substantial but imperfect barrier to CTL engagement. Effector memory and naive CD4⁺ T cells possess the additional barriers of superior Nef-mediated immunoevasion and cell-intrinsic CTL resistance, respectively, which allow for higher frequencies of intact proviruses to persist in Tem and Tn cells. Additional layers of diversity exist within these maturational subsets (depicted by cell membrane shading), and further dissecting each subset in relation to immunoevasion/resistance is a key frontier.