Progenitor mobilization in chimeric mice.

Animals chimeric for L-selectin (L+/+ or L−/−), and green fluorescence protein (EGFP) expression were generated by adoptive bone marrow transfer. Lethally irradiated P- and E-selectin doubly deficient recipient mice were injected with a mixture of bone marrow nucleated cells obtained from transgenic mice expressing EGFP and wild-type (L+/+) or L-selectin-deficient (L−/−) mice. Two weeks after transplantation, the mice were splenectomized and allowed to recover for 1 month. EGFP expressing progenitors also express L-selectin and can be distinguished from L+/+ and L−/− progenitors by their green fluorescence. L+/+ / EGFP and L−/−/EGFP splenectomized chimeric mice were then treated with 2 doses of fucoidan (FUC) or PBS over 6 hours. Blood mononuclear and bone marrow cells were plated to assess their progenitor content. The numbers of nonfluorescent and green fluorescent progenitors were determined using an inverted microscope equipped with a fluorescence source. A representative area containing colonies grown in methylcellulose media is shown using (A) light and (B) both light and fluorescence microscopy. The numbers of green fluorescent (arrow) and nonfluorescent (L+/+ in this photograph) colonies (arrowhead) were determined after 8 days of culture. (C), The ratios of green colonies in the blood and bone marrow were calculated by dividing the percentage green colonies in the blood by the percentage green colonies in the bone marrow. n = 3-5; *P < .05 compared with PBS-treated.