Platelets from LD express IIb and β3 subunits but little IIbβ3complex.
(A) Flow-cytometric analysis of surface αIIbβ3. Monoclonal antibodies directed against a control glycoprotein, GPIb (AP1), the αIIbβ3 complex (AP2), the β3subunit (AP3), or the αIIb subunit (TAB) were incubated with washed platelets from a healthy donor (control), the patient (LD), or the patient's father (F), and binding was assessed. Control platelet binding of nonimmune mouse IgG yielded a relative mean fluorescence of 2. (B) Western blot analysis of total platelet αIIbβ3. The indicated amounts of Triton X-100–treated platelet lysates from a healthy control, the patient (LD), and the patient's father (F) were separated by sodium dodecyl sulfate (SDS)–7% polyacrylamide gel electrophoresis, transferred to a polyvinylidene fluoride membrane, and detected with rabbit polyclonal antibodies against αIIb and β3. The positions of αIIb (upper arrow) and β3(lower arrow) are indicated.
