CD19 and lymphoma: CAR-T therapies have achieved great success in clinical trials for advanced B-cell malignancies, with CD19 CAR-T therapy leading to complete remission in many patients suffering from r/r B-cell leukemia/lymphoma.1,2 However, a high incidence of relapse with CD19− disease revealed in long-term follow-up data of CD19-targeting immunotherapy underscores the vulnerability of this therapeutic strategy to antigen escape.3–5