Moreover, the histamine dihydrochloride plus low-dose IL-2 regimen confers reduced relapse risk during the post-remission phase of AML through dual mechanisms (1): counteracting myeloid-derived immunosuppression (HDC component), and (2) activating anti-leukemic lymphocytes (including natural killer cells and cytotoxic T lymphocytes; IL-2 component) (21, 22). The gene discussed is IL2; the disease is acute myeloid leukemia.