Thus, CD19‐targeted, CD20‐targeted and BCMA‐targeted CAR T cells exhibit superior anti-tumor activity in B cell malignancies (1, 3, 67, 127), but they attack normal B cells as well, which could result in impaired humoral immunity, such as B cell aplasia and hypogammaglobulinemia (128–131). This evidence concerns the gene CD19 and neoplasm.