The activity of alpha1,6-fucosyltransferase during human megakaryocytic differentiation.
alpha1,6-Fucosyltransferase (6FucT, E.C. 2.4.1.68) is one of the enzymes involved in the synthesis of N-linked glycans of the GpIIb/IIIa complex (CD41a) which is present on megakaryocytes (MKs) and platelets. In this study, we examined 6FucT activity in ex vivo cultures of immunoselected cord blood CD34(+) cells grown in a medium promoting megakaryocytopoiesis. Our results show that the activity of 6FucT increased ahead of, and thereafter concomitantly with, cells expressing the CD41a antigen. When the CD41a(+) subpopulation of cells was immunoselected (using anti-CD61 i.e. anti-GpIIIa antibodies), its 6FucT activity increased proportionally to the yield of CD61(+)(+)(+) cells. Taking into account the heavy load of 6FucT in platelets and megakaryocytes, we regard this enzyme as a candidate for the earliest marker of MK-commitment in cultured hematopoietic stem cells. Such a marker should allow an earlier detection and earlier transplantation of patients' own, ex vivo expanded, Mk progenitors.
Bany-Łaszewicz
Urszula
U
Department of Biochemistry, Institute of Hematology and Blood Transfusion, Chocimska 5, 00-957 Warsaw, Poland. ubany@ihit.waw.pl
Kamińska
Joanna
J
Klimczak-Jajor
Edyta
E
Kościelak
Jerzy
J
D018952:Antigens, CD34 / Q000276:immunology*; D002454:Cell Differentiation / Q000502:physiology*; D002478:Cells, Cultured; D005647:Fucosyltransferases / Q000378:metabolism*; D005700:Galactosyltransferases / Q000378:metabolism*; D006801:Humans; D039661:Integrin beta3 / Q000276:immunology; D008533:Megakaryocytes / Q000166:cytology / Q000201:enzymology*; D040201:Platelet Membrane Glycoprotein IIb / Q000276:immunology
D018952:Antigens, CD34; D039661:Integrin beta3; D040201:Platelet Membrane Glycoprotein IIb; D005647:Fucosyltransferases; D005700:Galactosyltransferases; C119701:beta-1,4-galactosyltransferase I; C020559:Glycoprotein 6-alpha-L-fucosyltransferase