Effect of CCL18 on adherent cells in LTBMCs. Adherent layers from LTBMC were taken after 1 week of culture (Leica 10×/0.22 NA objective). Stromal fibroblast-like cells (A) and macrophage-like cells (B) are shown. (C) Effect of CCL18 on monocyte adhesion to fibronectin and vitronectin. Adhesion was determined as described in “Cell isolation and culture.” Results (mean ± SD) of 1 of 3 representative experiments are shown. Adhesion seen in the presence of 100 nM CCL18 was statistically different from that seen in unstimulated cells for both adhesion molecules (Student t test; *P < .01). (D) Effect of CCL18 on monocyte survival. Monocytes were isolated from peripheral blood (n = 4) or bone marrow (n = 2), cultured for 3 days, and stimulated with 40 nM CCL18 for 20 hours. Apoptosis was determined with an annexin V–FITC/propidium iodide staining kit in which viable cells remained unstained in the lower left quadrant of a FACS dot plot. Results of 1 representative experiment are shown. Cell viability ranged from 15% to 26% without stimulation and 36% to 44% in CCL18-stimulated cultures. (E) Effect of CCL18 on macrophage maturation. Monocytes were stimulated with 40 nM CCL18 or buffer control on day 2, cultured for 4 more days, and photographed (Leica 10×/0.22 NA objective).