Thrombin Induces a Rapid Redistribution of Glycoprotein Ib-IX Complexes Within the Membrane Systems
نویسنده
چکیده
Previous studies have shown a decreased binding of monoclonal antibodies (MoAbs) to glycoprotein (GP) Ib-IX complexes on thrombin-stimulated platelets, but the reason for this is poorly understood. We have used (1 1 immunofluorescence procedures and flow cytometry. and (2) immunogold staining and electron microscopy to investigate this phenomenon. Washed platelets were incubated with a-thrombin, adenosine diphosphate, or ionophore A23187 for increasing lengths of time. For a-thrombin, but not the other agonists, flow cytometry confirmed a doseand time-dependent decrease in the binding of MoAbs specific for GP lba (AP-1, Bx-1). GP IX (FMC 25). or to the complex itself (SZ 1). lmmunogold staining performed using standard transmission or scanning electron microscopy highlighted surface areas devoid of bound antibody. However, a quantitatively normal immunofluorescence was restored if
منابع مشابه
Thrombin induces a rapid redistribution of glycoprotein Ib-IX complexes within the membrane systems of activated human platelets.
Previous studies have shown a decreased binding of monoclonal antibodies (MoAbs) to glycoprotein (GP) Ib-IX complexes on thrombin-stimulated platelets, but the reason for this is poorly understood. We have used (1) immunofluorescence procedures and flow cytometry, and (2) immunogold staining and electron microscopy to investigate this phenomenon. Washed platelets were incubated with alpha-throm...
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