Immune response as a possible mechanism of long-lasting disease control in spontaneous remission of MLL/AF9-positive acute myeloid leukemia

Ann Hematol. 2012 Jan;91(1):27-32. doi: 10.1007/s00277-011-1332-y. Epub 2011 Sep 29.


Spontaneous complete remission (CR) is a rare, poorly understood phenomenon in acute myeloid leukemia (AML). We describe the 10-year follow-up of a patient with MLL-AF9-positive AML (Müller et al. Eur J Haematol 73:62-66, 2004), including ex vivo antileukemic immune responses which may contribute to the long-lasting spontaneous CR (tantamount to cure). We could demonstrate strong in vitro cytotoxic activity mediated by the patient's serum (cryopreserved at diagnosis 2001) against myeloid cell lines. We also addressed cellular cytotoxic activity against myeloid leukemia cells. When the patient's natural killer (NK) cells (obtained in 2007) were tested against the K562 cell line, upregulation of CD107 occurred, implying that long-term CR in this patient could be due to NK cell-mediated disease control.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, CD / immunology
  • Cytotoxicity, Immunologic / immunology*
  • Follow-Up Studies
  • Humans
  • Immunity / immunology*
  • K562 Cells
  • Killer Cells, Natural / immunology
  • Leukemia, Myeloid, Acute / genetics*
  • Leukemia, Myeloid, Acute / immunology*
  • Lymphocyte Activation
  • Male
  • Middle Aged
  • Myeloid Cells / cytology
  • Myeloid Cells / immunology
  • Myeloid-Lymphoid Leukemia Protein / genetics
  • Myeloid-Lymphoid Leukemia Protein / immunology*
  • Oncogene Proteins, Fusion / genetics
  • Oncogene Proteins, Fusion / immunology*
  • Remission, Spontaneous*
  • T-Lymphocytes / immunology
  • Tumor Cells, Cultured


  • Antigens, CD
  • MLL-AF9 fusion protein, human
  • Oncogene Proteins, Fusion
  • Myeloid-Lymphoid Leukemia Protein