Ongoing clinical trials have described durable rejection of previously refractory B-cell malignancies including chronic lymphocyte leukemia (CLL [16,17]; 51–77% remission), acute lymphocyte leukemia (ALL [13,18]; 68–93% remission) and diffuse large B cell lymphoma (DLBCL [19,20]; 68–86% remission), in patients after CD19-directed CAR therapy [10,21,22,23]. Here, CD19 is linked to B-cell chronic lymphocytic leukemia.