Antiphospholipid antibodies (aPL) are mandatory for the diagnosis but are also a risk factor for the antiphospholipid syndrome (APS) clinical manifestations. Lupus anticoagulant (LA), anticardiolipin (aCL), and anti-beta2 glycoprotein I (β₂GPI) assays are the formal laboratory classification/diagnostic criteria. Additional nonclassification assays have been suggested; among them, antiphosphatidylserine-prothrombin (aPS/PT) and antidomain 1 β₂GPI antibodies are the most promising ones although not yet formally accepted. aPL represent the example of a laboratory test that moved from dichotomous to quantitative results consistent with the idea that reporting quantitative data offers more diagnostic/prognostic information for both vascular and obstetric manifestations. Although the general rule is that the higher the aPL titer, the higher the test likelihood ratio, there is growing evidence that this is not the case for persistent low titers and obstetric events. LA displays the highest diagnostic/prognostic power, although some isolated LAs are apparently not associated with APS manifestations. Moreover, isotype characterization is also critical since IgG aPL are more diagnostic/prognostic than IgA or IgM. aPL are directed against two main autoantigens: β₂GPI and PT. However, anti-β₂GPI antibodies are more associated with the APS clinical spectrum. In addition, there is evidence that anti-β₂GPI domain 1 antibodies display a stronger diagnostic/prognostic value. This finding supports the view that antigen and even epitope characterization represents a further step for improving the assay value. The strategy to improve aPL laboratory characterization is a lesson that can be translated to other autoantibody assays in order to improve our diagnostic and prognostic power.

抗磷脂抗体 (aPL) 是诊断所必需的，但也是抗磷脂综合征 (APS) 临床表现的危险因素。狼疮抗凝剂 (LA)、抗心磷脂 (aCL) 和抗 β2 糖蛋白 I (β ₂ GPI) 检测是正式的实验室分类/诊断标准。已建议进行其他非分类分析；其中，抗磷脂酰丝氨酸-凝血酶原 (aPS/PT) 和抗结构域 1 β ₂GPI 抗体是最有前途的抗体，尽管尚未被正式接受。aPL 代表了一个实验室测试的例子，它从二分法到定量结果，与报告定量数据为血管和产科表现提供更多诊断/预后信息的想法一致。尽管一般规则是 aPL 滴度越高，测试似然比就越高，但越来越多的证据表明，对于持续的低滴度和产科事件，情况并非如此。LA 显示出最高的诊断/预后能力，尽管一些孤立的 LA 显然与 APS 表现无关。此外，同种型表征也很关键，因为 IgG aPL 比 IgA 或 IgM 更具诊断性/预后性。aPL 针对两种主要自身抗原：β ₂GPI 和 PT。然而，抗β ₂ GPI 抗体与 APS 临床谱更相关。此外，有证据表明抗 β ₂ GPI 结构域 1 抗体显示出更强的诊断/预后价值。这一发现支持以下观点，即抗原甚至表位表征代表了提高测定值的进一步步骤。改进 aPL 实验室表征的策略是一个教训，可以转化为其他自身抗体检测，以提高我们的诊断和预后能力。