CD19 and precursor B-cell acute lymphoblastic leukemia: Around the same time, other research groups in the US—at institutions such as the National Cancer Institute (NCI), CHOP, and Baylor College of Medicine—also identified CD19 as a highly promising tumor-associated antigen.49,85–87 These efforts collectively focused on treating B-cell-derived malignancies, including B-cell acute lymphoblastic leukemia (B-ALL), chronic lymphocytic leukemia (CLL), and B-cell non-Hodgkin lymphoma (B-NHL), which uniformly express CD19 on their surfaces (Fig. 2).