ERBB2 and juvenile myelomonocytic leukemia: The PB transposon has also been used to generate other CAR T cells, including anti-HER2 CAR T cells to treat HER2-positive tumors (24) and antigranulocyte-macrophage colony-stimulating factor receptor (GMR, CD116) CAR T cells to treat juvenile myelomonocytic leukemia (JMML) (25).