systemic BLP redirects leukocyte migration in vivo. (A) TLR2-null and WT macrophages (1.5 × 107 of each) labeled with spectrally different fluorescent makers were administered intravenously to TPA-painted D6-deficient mice (red TLR2-deficient cells and green WT cells). Concurrently, mice were intraperitoneally administered either BLP or saline and culled 24 hours later. LN were removed and cells examined by FACS to specifically determine numbers of dye-labeled macrophages that had migrated to the LN. Values shown represent the percentage of dye-labeled macrophages that were either WT or TLR2-null for individual mice. CD4 T cells were isolated from TLR2-deficient and WT mice and similarly labeled and injected (numbers as above) into TPA-treated mice that received either saline or BLP intraperitoneally and percentage of labeled cells migrating to LN determined by FACS. Statistical probability were determined with the Student t test (ns, not significant). (B) Identification of WT (green cells, green arrows) and TLR2-deficient cells (red cells, red arrows) in TPA-inflamed skin. The white bar on the right panel shows the positioning of a TLR2-deficient cell (red arrow) at an approximate distance of 200 μm from the epidermal surface (E). (C) Quantification of labeled macrophage numbers within TPA-painted skin from control and BLP-treated mice. These data are representative of data obtained from 3 separate experiments with 3 mice per group. Cell counts were from multiple (> 10) full-length skin sections per mouse.
