T cell memory phenotyping of SIV-infected rhesus macaques after tenofovir withdrawal. CD3 + 4+ T cells (A-D) and CD3 + 8+ T cells (E-H) from PBMC and tissue lymphoid cells collected at time of euthanasia were assessed via multiparameter flow cytometry. Values were compared to those of 3 uninfected animals. Data are reported as the frequency of CD4+ T cells (A) and CD8+ T cells (E) in the total lymphocyte population, or as the frequency of naïve cells, CD28 + CD95- (B,F), central memory cells, CD28 + CD95+ (C,G), and effector and effector memory cells, CD28- (D,H) within their respective CD4+ and CD8+ T cell populations. Animal 33091 is represented as a red square in all graphs.