Single-cell transcriptomic analysis reveals distinct B-cell populations in diagnostic and relapsed CHL. (A) UMAP visualization of B-cell subclusters in the discovery cohort. (B) Dot plot showing the top differentially expressed genes in each B-cell subclusters. The bubble size shows the percentage of cells with gene expression, and the color shows the scaled expression (by rows). (C) Proportional analysis of B-cell subclusters across diagnostic, early-relapse, and late-relapse CHL samples in the discovery cohort. Mann-Whitney U test was used for statistical analysis. (D) LGALS9 expression in naïve B cells across diagnostic, early-relapse, and late-relapse CHL, demonstrating significant upregulation in early-relapse samples in the discovery cohort. ∗P < .05; ∗∗P < .01. GCB, germinal center B cell; ns, not significant.