Binding of QITP antibodies to platelets, CHO-GPIb/IX cells, CHO-GPIIb/IIIa cells, and Mks. QITP antibodies (WJ) were bound in the presence (+Qn, red) and absence (−Qn, green) to the platelets, CHO cells expressing human GPIb/IX (CHOαβIX) or GPIIb/IIIa, and cultured Mks derived from CD34+ cells. Control NS plus Qn is shown in blue.