CD4 and acute lymphoblastic leukemia: When leukemia cells from a patient who exhibited T-cell acute lymphoblastic leukemia (T-ALL) to AML switch upon chemotherapy were transplanted into SCID mice, engrafted AML cells exhibited myeloid cell markers (such as CD33) as expected, but the cells exhibited T-cell markers (such as CD2, CD4, and CD7) similar to the T-ALL at diagnosis if the recipient mice were treated with cytokines GM-CSF or interleukin 3 (IL-3) (42).