Although it has been shown previously that HIV can establish latent infection in activated CD4+ T cells (110, 111) and that the peripheral blood HIV DNA load is higher in activated compared to resting cells in ART-treated individuals (112), the existence of latently infected CD4+ cells that are activated, and therefore relatively short-lived, suggests continuous replenishment of this component of the reservoir by cellular proliferation (113). This evidence concerns the gene CD4 and disease arising from reactivation of latent virus.