Kinoshita S, Yoshioka K, Tsujino G, Shindo T, Kasahara M, Tanaka K
Department of Pediatrics, Osaka National Hospital.
Rinsho Ketsueki. 1992 Apr;33(4):430-5.
Three cases of suspected variant thrombasthenia patients (out of 10 cases of Glanzmann's thrombasthenia), who had significant amounts of platelet GPIIbIIIa, underwent flow cytometry to analyse the binding capacity of monoclonal antibodies against GPIIbIIIa to platelets. The monoclonal antibodies used in this study were as follows: PLT-1 and AP-2 recognizing the IIbIIIa complex; TP 80, P2 and AP-4 recognizing IIb:;AP-5 recognizing IIIa;OP-G2, which binds an epitope near the RGD binding site and 3F11. OP-G2 also recognizes conformational changes of activated platelets by increased binding. Case 1 platelets showed a binding capacity of 28-63% of that of normal platelets for TP80, AP-2, AP-4, and 3F11, but no binding to OP-G2. Case 2 platelets also showed 16-44% binding with TP80, AP-2, AP-4, AP-5, and 3F11, but no binding to OP-G2. These findings indicated the presence of structural abnormalities of the functional site of platelet GPIIbIIIa in cases 1 and 2. Case 3 platelets bound with all monoclonal antibodies normally, but normal increase in the binding of OP-G2 to platelets activated by thrombin or ADP was not seen, indicating a lack of activation of the fibrinogen binding site of platelet GPIIbIIIa.
10例Glanzmann血小板无力症患者中有3例疑似变异型血小板无力症患者，其血小板GPIIbIIIa含量显著，对这些患者进行了流式细胞术分析，以检测抗GPIIbIIIa单克隆抗体与血小板的结合能力。本研究中使用的单克隆抗体如下：识别IIbIIIa复合物的PLT-1和AP-2；识别IIb的TP 80、P2和AP-4；识别IIIa的AP-5；结合RGD结合位点附近表位的OP-G2以及3F11。OP-G2还通过增加结合来识别活化血小板的构象变化。病例1的血小板对TP80、AP-2、AP-4和3F11的结合能力为正常血小板的28%-63%，但与OP-G2无结合。病例2的血小板与TP80、AP-2、AP-4、AP-5和3F11的结合率也为16%-44%，但与OP-G2无结合。这些发现表明病例1和病例2的血小板GPIIbIIIa功能位点存在结构异常。病例3的血小板与所有单克隆抗体的结合均正常，但未观察到OP-G2与凝血酶或ADP激活的血小板结合正常增加，这表明血小板GPIIbIIIa的纤维蛋白原结合位点缺乏激活。
