Leukemia is a disease that has gradually transitioned from clinical research to clinical treatment with the rapid development of oncology and immunology as well as molecular biology, and has become the star of attention at the 56th ASH Society this year.CIK and DC are the 2 main components of immunotherapy for hematologic tumors. CIK: It is obtained by co-culturing human peripheral blood mononuclear cells with various cytokines IFN-γ, IL-12, IL-2, etc. in vitro for a period of time, expressing both CD3 and CD56, and becoming NK cell-like T cells. These cells have strong proliferative ability, high tumor-killing activity and non-MHC restriction, with no obvious side effects on tumor and hematopoietic cells. DC: APC cells originated from bone marrow, the strongest antigen-presenting APC, which can effectively present tumor antigens to T cells, stimulate the activation and proliferation of primary T cells, and thus kill tumor cells. MRD is the root cause of leukemia recurrence in post-transplant patients, and eradication of MRD relies on efficient antigen presentation to T cells for recognition and killing of tumor antigens.