Association between CD19 splice variants at pretreatment or relapse and response. (A) CD19 splicing events scheme. (B) Distribution of CD19 splice variants in pretreatment biopsies by CD19 H-score. (C) Association between pretreatment CD19 gene (transcript per million) and protein expression (left) and their respective relationship with ongoing response (middle and right). (D) Sashimi plots depicting characteristic ASEs in representative biopsies. (E) Prevalence of CD19 splice variants in paired pretreatment-relapse biopsies. (F) CD19 splice variants in relapse biopsies shown in panel E. Numbers denote impacted exons. (G) Response (left) and CD19 H-score (right) of patients shown in panel E. (H) Integrated Genomics Viewer snapshots showing CD19 mutations detected in paired pretreatment-relapse biopsies (representative patient 10). Blank, others; NR, nonresponder; O, ongoing response; Pt., patient; RE, relapsed.