HES1 and acute lymphoblastic leukemia: To define the hL-IC signature in relapsed TAL/LMO T-ALL samples, we sorted CD7+CD1a− hL-ICs from the CD7+CD1a+ DP leukemic cells from REL-14 and REL-13 patient xenografts (Supplementary Fig. 6A, B) and compared gene expression profiles (Supplementary Fig. 6C).