THE RECEPTOR FOR IGE ON BLOOD-PLATELETS
THE RECEPTOR FOR IGE ON BLOOD-PLATELETS
复制标题
DOI：
10.1002/eji.1830160318
复制
发表时间：
1986-03-01
影响因子：
5.4
通讯作者：
AURIAULT, C
中科院分区：
文献类型：
--
作者：
JOSEPH, M;CAPRON, A;AURIAULT, C
人和大鼠的高纯度血小板可通过依赖IgE的机制诱导为抗血吸虫幼虫的细胞毒效应。这一过程意味着这些血液成分表面存在IgE Fc部分的受体。在感染患者的血清和哮喘患者富含IgE的血清中孵育的正常血小板显示出类似的能力。流式细胞荧光分析表明，携带IgE受体的血小板为一个亚群(20%)，在大鼠或高循环IgE水平的患者中，其百分比显著增加(高达50%)。放射性标记的IgE，其结合被过量的未标记的IgE或抗Fc-epsilon特异性地抑制。受体抗体，可以证明血小板表面这种同种类型的受体是饱和的。增加的IgE结合量呈双峰曲线，每个血小板少于1000个结合部位，亲和系数为3.3倍。低浓度时为10~(-7)M~(-1)，Ka为7.8倍。浓度较高时为10-5M-1。除了对展示血小板的细胞毒性特性感兴趣外，这些观察还强调了血小板通过特定的受体与IgE抗体分子直接相互作用而在即刻类型过敏反应中的潜在作用。
Highly purified blood platelets from man and rat could be induced into cytotoxic effectors against schistosome larvae by an IgE-dependent mechanism. Such a process implied the existence of a receptor for the Fc part of IgE on the surface of these blood elements. Normal platelets, incubated in the serum of infected individuals as well as in the IgE-rich serum from asthmatic patients, showed similar capabilities. Flow cytofluorometric analysis evidenced that the platelets bearing IgE receptors represented a subpopulation (20%), the percentage of which was significantly increased (up to 50%) in rats or patients with high levels of circulating IgE. Radiolabeled IgE, whose binding was specifically inhibited by an excess of unlabeled IgE or by anti-Fc.epsilon. receptor antibody, allowed the demonstration that the receptor for this isotype on the platelet surface was saturable. The binding of increasing amounts of IgE followed a bimodal curve, with less than 1000 sites per platelet showing an affinity coefficient of 3.3 .times. 10-7 M-1 at low concentrations, and a Ka of 7.8 .times. 10-5 M-1 for higher concentrations. Beyond their interest in the demonstration of cytotoxic properties of thrombocytes, these observations place emphasis on the potential role of the platelets in immediate-type allergic reactions by their direct interaction with IgE antibody molecules, through a specific receptor.