[Detection of soluble forms of platelet membrane glycoproteins and its clinical significance].
Soluble forms of surface membrane glycoproteins of various cell types have been identified as makers for in vivo or in vitro cellular events, in which the receptors are involved. Using mouse monoclonal antibodies, sandwich ELISA systems to quantitate plasma concentrations of two platelet glycoproteins in soluble form were set up: one is glycocalicin (GC), a proteolytic fragment of GP Ib alpha chain and the other is GMP-140 or CD62 (GMP) known as a target for leukocyte recruitment at vascular injury sites. As in vivo markers, GC is said to reflect platelet turnover. High levels of plasma GMP were detected in patients with thrombotic thrombocytopenic purpura, being presumably indicative of microcirculation disorder. During storage of platelet concentrates, plasma levels of both markers were increased in a time-dependent fashion over 10 days. This correlated with a decrease in the surface expression of the glycoproteins on platelets, suggesting that the soluble glycoproteins entering the supernatants by proteolysis would be an useful indicator for in vitro alteration of stored platelets surface.
Handa
M
M
Blood Center, Keio University Hospital.
Katayama
M
M
Ikeda
Y
Y
D015415:Biomarkers / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D015539:Platelet Activation; D010980:Platelet Membrane Glycoproteins / Q000032:analysis*; D011697:Purpura, Thrombotic Thrombocytopenic / Q000175:diagnosis*; D012995:Solubility
D015415:Biomarkers; D010980:Platelet Membrane Glycoproteins