Expression of the thrombospondin receptor (CD36) on the cell surface in megakaryoblastic and promegakaryocytic leukemias: increment of the receptor by megakaryocyte differentiation in vitro.
In this report we describe four cases of acute megakaryocytic leukemia demonstrated by the presence of megakaryocyte-platelet-related cell-surface antigens. These were detected utilizing flow cytometry and monoclonal antibodies in addition to both platelet peroxidase activity, which was shown by ultrastractural cytochemistry, and emergence of differentiation antigens, while culturing these leukemic cells. The blasts of one patient possessed both platelet GpIb and GpIIb/IIIa cell-surface antigens detected by AN51(CD42b), J15, P2, and HPL2(CD41), respectively, whereas the remaining three patients almost completely lacked GpIb cell-surface antigen. Hence the former were diagnosed as immature(pro)megakaryocytic leukemia and the latter as acute megakaryoblastic leukemia from the viewpoint of immunophenotypic analysis. While we cultured these leukemic cells in conditioned medium prepared from phytohemagglutinin-stimulated leukocytes and interleukin 3, expression of CD36(OKM5) antigen (thrombospondin receptor) increased gradually according to the differentiation and maturation of these cells. Finally, all leukemic cells differentiated to mature megakaryocytes. The function of CD36 on these cells remains to be elucidated.
Imamura
N
N
Department of Internal Medicine, Hiroshima University, Japan.
Ota
H
H
Abe
K
K
Kuramoto
A
A
D015703:Antigens, CD / Q000235:genetics / Q000502:physiology*; D018955:CD36 Antigens; D002454:Cell Differentiation; D002478:Cells, Cultured; D006801:Humans; D007947:Leukemia, Megakaryoblastic, Acute / Q000276:immunology*; D008533:Megakaryocytes / Q000166:cytology; D010641:Phenotype; D010980:Platelet Membrane Glycoproteins / Q000032:analysis
D015703:Antigens, CD; D018955:CD36 Antigens; D010980:Platelet Membrane Glycoproteins