Changes in platelet membrane glycoproteins before bone marrow transplantation and after engraftment--a pilot study.
Thrombotic complications are observed in patients undergoing bone marrow transplantation despite thrombocytopenia and impaired coagulation due to liver function disturbances. Endothelial cell damage which is involved in the pathogenesis of major transplant related complications like graft-versus-host disease, veno-occlusive disease, sepsis or microangiopathy may be a contributing factor. Little is known about platelet function in bone marrow transplant recipients. In order to study functional alterations in circulating platelets we investigated unstimulated and ADP-stimulated platelets of 10 bone marrow transplant recipients ex vivo by flow cytometry in a pilot study using a panel of monoclonal antibodies to characterize changes in membrane glycoproteins. Samples were collected before and during conditioning and at three timepoints after engraftment. 10 healthy volunteers served as controls. Platelets of bone marrow transplant recipients showed partly a significant, higher expression of surface bound fibrinogen, activated fibrinogen receptor, and glycoprotein Ib as compared to controls. P-selectin, a marker of platelet degranulation was significantly elevated after ADP-induced stimulation at all timepoints compared to controls. Only marginal differences were found for GP IIb/IIIa surface expression. The data point to an increased platelet activation state in bone marrow transplant recipients which might contribute to the thrombotic phenomena observed in these patients.
Neumeister
P
P
Division of Haematology, Department of Internal Medicine, Karl-Franzens-University Graz, Auenbruggerpl. 38, A-8036 Graz, Austria. peter.neumeister@kfunigraz.ac.at
Hiller
E
E
Gawaz
M
M
Holler
E
E
Kolb
H J
HJ
Sill
H
H
Pihusch
R
R
Mempel
W
W
Wittmann
G
G
Salat
C
C
D000244:Adenosine Diphosphate / Q000494:pharmacology; D000328:Adult; D000911:Antibodies, Monoclonal; D016026:Bone Marrow Transplantation / Q000009:adverse effects / Q000502:physiology*; D016022:Case-Control Studies; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D006085:Graft Survival / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D019007:P-Selectin / Q000097:blood; D015539:Platelet Activation / Q000187:drug effects / Q000502:physiology; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000378:metabolism; D010980:Platelet Membrane Glycoproteins / Q000378:metabolism*; D011796:Quinacrine; D013927:Thrombosis / Q000097:blood / Q000209:etiology; D019172:Transplantation Conditioning
D000911:Antibodies, Monoclonal; D005456:Fluorescent Dyes; D019007:P-Selectin; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D010980:Platelet Membrane Glycoproteins; D000244:Adenosine Diphosphate; D005340:Fibrinogen; D011796:Quinacrine