Antiphospholipid Antibody Heterogeneity

描述(由申请人提供)：抗磷脂综合征的特征是自然产生的抗磷脂抗体和增加的妊娠丢失或各种产科并发症的风险。抗磷脂抗体针对磷脂依赖抗原、磷脂结合蛋白或它们的组合。关于特定抗体特异性与病理生理学的相关性和关系的信息很少。大量数据支持胎盘滋养层细胞是抗磷脂抗体的主要细胞靶点的说法。假设抗磷脂抗体诱导的妊娠丢失是通过选择抗体亚群直接与滋养细胞结合而发生的，从而对胎盘发育产生不利影响。其中一些影响涉及滋养层表面的血栓形成，但大多数是非血栓形成，导致滋养层细胞分化不完全。基于初步数据的预测是，最相关的抗体将是针对磷脂酰丝氨酸依赖的抗原。为了验证这一假设，将实现以下目标。目的1研究抗磷脂抗体在个体患者中的异质性。这一目的是为了确定个体妊娠丢失患者对相关磷脂和磷脂结合蛋白的反应谱。单个抗磷脂抗体将根据抗原特异性进行纯化和鉴定。目的2将利用单细胞聚合酶链式反应技术克隆个体患者的抗磷脂抗体。其目标是克隆至少3名患者体内存在的每一种相关抗体。克隆的抗体将被鉴定。目的3探讨抗滋养层细胞抗体特异性与生物学活性的关系。在AIMS I和AIMS 2中制备的试剂将被测试对滋养层细胞的反应性。这些反应包括与正常胎盘组织结合，与体外分化的滋养层细胞结合，抑制滋养层细胞侵袭，抑制滋养层细胞间融合，诱导细胞凋亡。这将是第一次深入研究个体患者的抗磷脂抗体谱，并将这些数据与对胎盘滋养层细胞的影响相关联。

DESCRIPTION (provided by applicant): The Antiphospholipid Syndrome is characterized by naturally occurring antiphospholipid antibodies and increased risk of pregnancy loss or a variety of obstetric complications. Antiphospholipid antibodies are directed against phospholipid-dependent antigens, phospholipid-binding proteins, or a combination of these. There is little information concerning the relevance and relationship of particular antibody specificities to pathophysiology. Considerable data support the proposal that the placental trophoblast is a primary cellular target of antiphospholipid antibodies. The hypothesis is that antiphospholipid antibody-induced pregnancy loss occurs through the binding of a select subgroup of antibodies directly with trophoblast resulting in detrimental effects on placental development. Some of these effects involve thrombosis on the trophoblast surface, but most are non-thrombotic and result in incomplete trophoblast differentiation. A prediction, based on preliminary data, is that the most relevant antibodies will be against phosphatidylserine-dependent antigens. To test this hypothesis, the following Aims will be addressed. Aim 1 will investigate the heterogeneity of antiphospholipid antibodies within individual patients. This Aim is designed to determine within individual pregnancy loss patients the spectrum of reactivities against relevant phospholipids and phospholipid-binding proteins. Individual antiphospholipid antibodies will be purified based on antigenic specificity and characterized. Aim 2 will clone antiphospholipid antibodies from individual patients using single cell PCR techniques. The goal is to clone each relevant antibody present in a minimum of 3 individual patients. The cloned antibodies will be characterized. Aim 3 will investigate the relationship between antibody specificity and biological activity against trophoblast. Reagents prepared in Aims I and 2 will be tested for reactivity against trophoblast. These reactivities will include binding to normal human placental tissue, binding to trophoblast undergoing differentiation in vitro, inhibition of trophoblast invasion, inhibition of intertrophoblast fusion, and induction of apoptosis. This will be the first study to thoroughly investigate the spectrum of antiphospholipid antibodies in individual patients and correlate those data to effects on placental trophoblast.