Effect of ZOL on colony formation from JMML and normal BM cells. (A) The percentages of the number of colonies in the culture of JMML and normal BM cells without and with 10 ng/mL GM-CSF, respectively, in the presence of various concentrations of ZOL to that in the absence of ZOL, and the proportion of G and GM colonies in total colonies under the respective conditions. The values indicate the means calculated from the data for 8 patients with JMML and 6 healthy donors in Table 1. ▪ indicates GM colonies; ▦, G colonies. (B) The numbers of cells contained in individual colonies cultured from JMML and normal BM cells without and with 10 ng/mL GM-CSF, respectively. Fifteen colonies were randomly chosen in the culture of BM cells of 3 patients with JMML and 3 healthy donors under the respective conditions. Bars indicate the means of cell numbers of the 15 colonies. In i, NS indicates not significant; ☆, P < .01; ★, P < .001. In ii, ☆ indicates P < .05; ★, P < .001.