TY - JOUR
T1 - IgG platelet antibodies in EDTA-dependent pseudothrombocytopenia bind to platelet membrane glycoprotein IIb
AU - Fiorin, Francesco
AU - Steffan, Agostino
AU - Pradella, Paola
AU - Bizzaro, Nicola
AU - Potenza, Rocco
AU - De Angelis, Vincenzo
PY - 1998/8
Y1 - 1998/8
N2 - EDTA-dependent pseudothrombocytopenia (PTCP) consists of an inappropriate low platelet count caused by autoantibodies present in the serum samples reacting with platelets only in EDTA-anticoagulated blood. By using immunoprecipitation and Western blot techniques, we studied the immunochemical specificity of platelet agglutinating autoantibodies in the serum samples of 10 patients with PTCP. Furthermore, to evaluate a possible role of PTCP-associated IgG autoantibodies in increased platelet turnover, we assayed the plasma glycocalicin (GC) level and calculated the GC index for every patient. Our results provide direct evidence that an epitope located on platelet membrane glycoprotein IIb is recognized by PTCP-associated IgG antibodies; moreover, GC levels in patients with EDTA-dependent PTCP were similar to control levels, thus excluding an increased platelet turnover. We conclude that antiplatelet antibodies directed against platelet cryptantigens are unlikely to have a major role in the increased removal of cells from circulation.
AB - EDTA-dependent pseudothrombocytopenia (PTCP) consists of an inappropriate low platelet count caused by autoantibodies present in the serum samples reacting with platelets only in EDTA-anticoagulated blood. By using immunoprecipitation and Western blot techniques, we studied the immunochemical specificity of platelet agglutinating autoantibodies in the serum samples of 10 patients with PTCP. Furthermore, to evaluate a possible role of PTCP-associated IgG autoantibodies in increased platelet turnover, we assayed the plasma glycocalicin (GC) level and calculated the GC index for every patient. Our results provide direct evidence that an epitope located on platelet membrane glycoprotein IIb is recognized by PTCP-associated IgG antibodies; moreover, GC levels in patients with EDTA-dependent PTCP were similar to control levels, thus excluding an increased platelet turnover. We conclude that antiplatelet antibodies directed against platelet cryptantigens are unlikely to have a major role in the increased removal of cells from circulation.
KW - Glycocalicin
KW - Platelet antibodies
KW - Platelet glycoprotein IIb
KW - Pseudothrombocytopenia
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M3 - Article
C2 - 9704616
AN - SCOPUS:0031849381
VL - 110
SP - 178
EP - 183
JO - American Journal of Clinical Pathology
JF - American Journal of Clinical Pathology
SN - 0002-9173
IS - 2
ER -