Neutrophils promote the release of alpha-6-fucosyltransferase from blood platelets through the action of cathepsin G and elastase.
Human blood platelets release alpha-6-fucosyltransferase during coagulation of blood or after stimulation with thrombin or other agonists that cause platelet activation (Antoniewicz et al., FEBS Lett. 244 (1989) 388-390). However, in the absence of neutrophils the thrombin-stimulated platelets release only a small fraction of alpha-6-fucosyltransferase activity (Kościelak et al., Acta Biochim. Polon. 42 (1995) 35-40). We show that the effect of neutrophils is reproduced by cathepsin G or (less efficiently) by elastase, the two enzymes that are released by neutrophils during coagulation of blood. We have also localized alpha-6-fucosyltransferase to membrane and alpha-granule fractions of platelets that had been disrupted by nitrogen cavitation. It is concluded that thrombin-activated neutrophils release cathepsin G and elastase that promote degranulation of platelets and hence the secretion of alpha-6-fucosyltransferase.
Kamińska
J
J
Department of Biochemistry, Institute of Hematology and Blood Transfusion, ul. Chocimska 5, 00-957 Warsaw, Poland.
Musielak
M
M
Nowicka
A
A
Wozniewicz
B
B
Kościelak
J
J
D000244:Adenosine Diphosphate / Q000494:pharmacology; D001792:Blood Platelets / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D056649:Cathepsin G; D002403:Cathepsins / Q000378:metabolism* / Q000494:pharmacology; D002478:Cells, Cultured; D005647:Fucosyltransferases / Q000378:metabolism*; D006801:Humans; D019272:Leukocyte Elastase / Q000378:metabolism* / Q000494:pharmacology; D009504:Neutrophils / Q000201:enzymology* / Q000502:physiology; D012697:Serine Endopeptidases / Q000378:metabolism*; D013917:Thrombin / Q000494:pharmacology
D000244:Adenosine Diphosphate; D005647:Fucosyltransferases; C020559:Glycoprotein 6-alpha-L-fucosyltransferase; D002403:Cathepsins; D012697:Serine Endopeptidases; C534094:CTSG protein, human; D056649:Cathepsin G; D019272:Leukocyte Elastase; D013917:Thrombin