Increased IL-1 receptor expression in CML LSC. IL-1RAP (A) and IL-1R1 (B) expression on human CML and normal CD34⁺CD38⁻CD90⁺ stem cells measured by flow cytometry. IL-1α levels in PB of CML patients and healthy controls measured by ELISA (C). Effect of human IL-1α exposure on IL-1R1 and IL-1RAP expression in CML stem cells (n = 4) (D). Effect of human CML and normal BM CM on IL-1R1 and IL-1RAP expression in CML (n = 4) (E) and normal (n = 3) (F) stem cells. IL-1R1 and IL1-RAP messenger RNA expression in CD34⁺ cells from CML patients after 7 days of imatinib treatment, as measured in microarray analysis, with 2 separate probes for each gene (G). Results represent mean ± SEM. Significance values: *P < .05; **P < .01, unpaired Student t test, 2-way ANOVA. MCF, median channel fluorescence.