Figure 4

In situ proliferation of Lin⁻ cells at the site of inflammation.

(a) Schematic overview of DNCB treatment, Lin⁻ cell transplantation and BM egress inhibition. FTY-720 or DOP was added to the drinking water for 3 days, beginning 1 day after transplantation of Lin⁻ cells. (b) Dorsal bioluminescence images of transplanted (5 × 10⁵ of Luc-Tg Lin⁻ cells) and drug-treated mice. Total photon flux values from the right ear were measured and fold increases between days 1 and 3 post-drug treatment are shown. (c) Flow cytometric analyses of CD45.1⁺Lin⁻ cells in the skin and BM of the transplanted (1 × 10⁶ of Lin⁻ cells from CD45.1⁺ mice) and drug-treated dermatitis mice on day 5 post-transplantation; representative data are shown. The percentage of CD45.1⁺ cells in the leukocytes present in skin or BM cells and the numbers of CD45.1⁺ cells in the skin and BM per mouse are plotted. (d) DNCB-treated, CD45.1⁺Lin⁻ cell-transplanted and FTY-720-treated mice were injected with 1 mg of BrdU daily for 3 days. FTY-720 was added to drinking water continuously until day 4 starting from day 1 post-transplantation. Leukocytes were isolated from the skin and stained with anti-CD45.1-APC and anti-BrdU-FITC antibodies. Representative flow cytometric data shown are gated for CD45.1⁺ cells. Data shown (b–d) are representative of two independent experiments (n = 5 mice/group/experiment). Data (b,c) are presented as means ±SEM. P values were determined using two-tailed unpaired Student’s t-tests; ns, not significant, *P < 0.05, **P < 0.01.