B3GAT1 and T-cell large granular lymphocyte leukemia: A patient cohort profiled with flow cytometry validated that patients with T-LGLL had a significantly higher percentage of mature terminally differentiated, antigen-experienced CD4+CD57+ T cells39,40 when compared with the healthy controls (P < 0.05, Mann-Whitney test, Fig. 4c, Supplementary Fig. 13e–g).