CD19 and acute lymphoblastic leukemia: Among hematologic malignancies, the most common target has been CD19 for which CAR-T cells have been FDA approved for use in several lymphoid malignancies, including B-cell acute lymphoblastic leukemia (ALL) and B-cell non-Hodgkin’s lymphomas (NHL) including diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), and follicular lymphoma (FL) [1,2].