Calcium Ions and the Conformation of Glycoprotein lila That is Essential for Fibrinogen Binding to Platelets: Analysis by a New Monoclonal Anti-GP lila Antibody, TM83
نویسندگان
چکیده
Using a newly developed murine monoclonal antibody (MoAb). TM83. against glycoprotein lIla (GPIIIa) of human platelets, we have analyzed the relationship between platelet fibrinogen binding and conformational changes in GPIIIa under EDTA treatment. Crossed radioimmunoelectrophoresis demonstrated that TM83 reacted with only the GPIIb/lIla complex but also with GPllla alone. TM83 dosedependently inhibited both thrombin-induced aggregation and fibrinogen binding to activated platelets. 125I-TM83 bound to an average of 20.890 ± 1 .600 (mean ± SE, n = 12) sites on a resting platelet. with Kd = 2.06 nmol/L in the presence of Ca2 . When platelets were incubated in 2 nmol/L EDTA-containing medium. pH 7.4. at 22’C for 30 minutes. binding of TM83 decreased to 70% of the control
منابع مشابه
Calcium ions and the conformation of glycoprotein IIIa that is essential fibrinogen binding to platelets: analysis by a new monoclonal anti-GP IIIa antibody, TM83.
Using a newly developed murine monoclonal antibody (MoAb), TM83, against glycoprotein IIIa (GPIIIa) of human platelets, we have analyzed the relationship between platelet fibrinogen binding and conformational changes in GPIIIa under EDTA treatment. Crossed radioimmunoelectrophoresis demonstrated that TM83 reacted with only the GPIIb/IIIa complex but also with GPIIIa alone. TM83 dose-dependently...
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