CD4 and acute lymphoblastic leukemia: So far, many studies have explored CAR‐T therapies that target CD7, CD5, CD4, CD1a, and T cell receptors β constant 1 (TRBC1) in the treatment of T‐ALL.[14, 15, 16, 17, 18] The expression of CD5 on the surface of malignant T cells but not hematopoietic stem cells makes it a good target for T‐ALL.