Antiplatelet antibodies in chronic adult immune thrombocytopenic purpura: assays and epitopes.
Antiplatelet antibodies in chronic adult immune thrombocytopenic purpura: assays and epitopes.
复制标题
慢性成人免疫性血小板减少性紫癜中的抗血小板抗体：测定和表位。
DOI：
10.1097/00043426-200312001-00013
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
McMillan,Robert
中科院分区：
文献类型：
--
作者：
McMillan,Robert
慢性免疫性血小板减少性紫癜（ITP）是一种自身免疫性疾病，其特征是由于自身抗体诱导的血小板破坏而导致血小板减少。这些自身抗体中的大多数针对糖蛋白（GP）IIb-IIIa或GPIb-IX上的表位。较新的抗原特异性自身抗体检测能够检测血小板相关和血浆自身抗体，并在免疫性血小板减少症的诊断中具有明确的作用。阳性检测为慢性ITP和其他可能发生免疫性血小板减少症的疾病（如胶原血管病和淋巴组织增生性疾病）中存在免疫性血小板减少症提供了有力证据。然而，阴性检测并不能排除ITP的存在。有些令人担忧的是，大量患者的检测结果呈阴性。讨论了这些观察结果的几种可能的解释。最近的研究已经将一些ITP自身表位定位于GPIIb-IIIa和GPIb-IX的特定区域。GPIIb-IIIa上的大多数自身表位是构象的，鉴于它们对二价阳离子的依赖性，并且定位于GPIIb的N-末端部分，而已经鉴定的GPIb-IX自身表位定位于GPIb氨基酸333-341。
Chronic immune thrombocytopenic purpura (ITP) is an autoimmune disorder characterized by thrombocytopenia due to autoantibody-induced platelet destruction. The majority of these autoantibodies are directed to epitopes on either glycoprotein (GP) IIb-IIIa or GPIb-IX. The newer antigen-specific autoantibody assays are capable of detecting both platelet-associated and plasma autoantibodies and have a definite role in the diagnosis of immune thrombocytopenia. A positive assay provides strong evidence for the presence of immune thrombocytopenia both in chronic ITP and in other diseases where immune thrombocytopenia may occur, such as collagen vascular disease and lymphoproliferative disorders. However, a negative assay does not rule out the presence of ITP. Somewhat concerning is the large number of patients who have negative assays. Several possible explanations for these observations are discussed. Recent studies have localized some ITP autoepitopes to specific regions of GPIIb-IIIa and GPIb-IX. Most autoepitopes on GPIIb-IIIa are conformational, in view of their dependence on divalent cations, and are localized to the N-terminal portion of GPIIb, while the GPIb-IX autoepitopes that have been identified are localized to GPIb amino acids 333–341.