Bulk CD4 T cells, which comprise a mix of resting and activated cells at baseline, and T cell subsets, some of which would be latently infected, were isolated and cultured for 72 hours in the presence or absence of the above drugs, along with RAL/TFV to prevent spreading infection, then reactivated with antiCD3/CD28, and cell associated HIV DNA and supernatant HIV p24 levels were measured after 48h (Fig 3A). This evidence concerns the gene CD28 and infection.