Distinct TLR-ligands differentially enhance the frequencies and activation of monocytes in draining LNs. (A) The total monocyte population was identified within the SSC-A^hiFSC-A^hi LN cells as the CD3⁻CD8⁻CD20⁻ HLA-DR⁺ population. Kinetics of frequencies of total monocytes within the LNs were assessed at days 1 and 3 after TLR-L injection. (B) Kinetics of frequencies of the CD14⁺CD16⁻ (gray), CD14⁺CD16⁺ (red), and CD14^dimCD16⁺⁺ (blue) subpopulations within the total LN monocytes were defined at days 1 and 3 after TLR-L injection. Statistical analysis in panels A and B indicates significant change relevant to baseline. Data are means ± SEM. *P < .05; **P < .01; ***P < .001 by t test. Activation phenotypes of the CD14⁺CD16⁻ (C) and CD14⁺CD16⁺ (D) monocytes were measured by expression of the surface markers CCR7, CCR5, CD80, and CD86 at days 1 and 3 after TLR-L injection. Histograms represent the isotype control (gray), baseline at day −12 (black) and at day 1 (green) and day 3 (red) after TLR-L injection. A single representative animal is shown for each experimental group.