c-Kit receptor (CD117) expression on myeloblasts and white blood cell counts in acute myeloid leukemia.
BACKGROUND
The c-Kit receptor is considered to play a crucial role in hematopoiesis. Induction of mobilization of hematopoietic cells in the bone marrow requires cooperative signaling through c-Kit and c-Kit ligand pathway, and these interactions are important in the retention of stem cells within the bone marrow. Therefore, we analyzed c-Kit density on the leukemic myeloblasts of patients with acute myeloid leukemia (AML) in relation to white blood cell count (WBC) in the peripheral blood.


METHODS
Bone marrow aspirates collected from patients with AML and bone marrow aspirates and leukapheresis products after granulocyte colony-stimulating factor blood mobilization from adult volunteers were studied. To determine the level of c-Kit receptor expression, we applied quantitative (relative fluorescence intensity and antibody binding per cell) cytometric methods.


RESULTS
Our data showed negative correlation between the level of c-Kit expression intensity on myeloblasts and the number of leukocytes in blood of AML patients. The c-Kit receptor density on myeloblasts in patients with low WBC was significantly stronger than that on myeloblasts in patients with high WBC. In the latter patient group, the density c-Kit receptor on myeloblasts was similar to that on CD34(+) cells in mobilized peripheral blood.


CONCLUSIONS
The obtained data suggest an involvement of c-Kit receptor in the regulation of leukemic myeloblasts egress to the peripheral blood.
Department of Physiopathology, Institute of Haematology and Blood Transfusion, Warsaw, Poland. jolwoz@poczta.onet.pl
Jolanta
J
Woźniak
Joanna
J
Kopeć-Szlezak
D005260:Female; D005434:Flow Cytometry; D042381:Granulocyte Precursor Cells / Q000378:metabolism*; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism* / Q000473:pathology*; D007958:Leukocyte Count; D007962:Leukocytes / Q000473:pathology*; D008297:Male; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*
D019009:Proto-Oncogene Proteins c-kit