TLR ligands preferentially activate CD4+ central memory and effector memory T cells and CD8+ effector memory T cells.

<p>Intracellular Ki-67 expression (3A, 3C) and cell surface CD69 (3B, 3D) were analyzed after 7 days' incubation of PBMC in medium alone, or in medium supplemented with plate bound anti-CD3 antibodies, or the indicated TLR ligand. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0001915#pone-0001915-g003" target="_blank">Figures 3A and B</a> are representative results among phenotypically defined naïve (CD45RA⁺CD45RO⁻CCR7⁺), central memory (CD45RA⁻CD45RO⁺CCR7⁺), and effector memory (CD45RA⁻CD45RO⁺CCR7⁻) CD4⁺ and CD8⁺ T cells. Values represent percentages of cells staining for Ki-67 or CD69. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0001915#pone-0001915-g003" target="_blank">Figures 3C and 3D</a> reflect the mean data from 15 separate experiments. Values nominally significantly different from medium alone values (Wilcoxon Sign Rank Test) are shown with an asterisk.