DT conjugated with interleukin-2 (IL-2) such as Denileukin and Diftitox (Ontak) have been produced to target hematologic malignancies such as adult T cell leukemia (ATL), chronic lymphocytic leukemia, Hodgkin’s and non-Hodgkin’s lymphomas, cutaneous T cell lymphoma (CTCL) and other leukemia and lymphomas [354]. The gene discussed is IL2; the disease is leukemia.