CD4 and infection: At day 5 post-infection non-proliferating (eFluor670hiEGFP−) CD4+ T-cells were sorted and cultured with phytohemagglutinin (PHA)-stimulated feeder peripheral blood mononuclear cells (PBMC), where the number of EGFP+ cells was quantified by flow cytometry as a surrogate marker of inducible latent infection.