Department of Cardiac Thoracic and Vascular Sciences, University of Padova, via Giustiniani, 2-35128 Padova, Italy.
Thromb Res. 2011 Dec;128(6):583-6. doi: 10.1016/j.thromres.2011.04.021. Epub 2011 May 26.
Antiphospholipid Syndrome (APS) is characterized by the presence of circulating antiphospholipid antibodies in patients with thrombosis or pregnancy morbidity. Antibodies involved in these disorders are mainly those directed against β(2)-Glycoprotein I (β(2)GPI) with the major epitope apparently located on discontinuous antigen with several parts of Domain I (DmI) involved. The relation between anti-DmI antibodies and patients' risk categories is unknown.
The synthetic full-length and correctly-folded DmI (1-64) to set up a competitive inhibition enzyme-linked immunoadsorbent assays (ELISA) was used. Plasma of 22 patients with APS and triple positivity [Lupus Anticoagulant positive (LAC+), IgG anti-cardiolipin positive (aCL+), IgG anti-β(2)GPI positive (a β(2)GPI +)], 15 with double positivity (IgG aCL+, IgG aβ(2)GPI+), 9 with single positivity (IgG aβ(2)GPI+) and 20 controls were evaluated.
Median of percentage inhibition was 25.5% [interquartile range (IQR)17.2-33.0] in triple positive patients. Significantly lower inhibition was observed in patients with double positivity, median inhibition 5.0% (IQR 0.0-27.0) and in patients with single positivity median inhibition was 2.0% (IQR 0.5-8.0) (p<0.0001). No inhibition was detected in control subjects or using β(2)GPI peptides (40-52 and 57-70), or when antithrombin, an insignificant control protein was used.
High risk patients with APS and triple laboratory positivity as compared with double and single positivity patients have significantly higher titre of anti-DmI antibodies as evaluated by an inhibition test.
抗磷脂综合征（APS）的特征是血栓形成或妊娠发病患者中存在循环抗磷脂抗体。这些疾病中涉及的抗体主要是针对β(2)-糖蛋白 I（β(2)GPI）的抗体，主要表位显然位于不连续抗原上，涉及结构域 I（DmI）的几个部分。抗 DmI 抗体与患者危险类别的关系尚不清楚。
使用合成全长且正确折叠的 DmI（1-64）建立竞争性抑制酶联免疫吸附测定（ELISA）。评估了 22 名 APS 患者和三重阳性患者[狼疮抗凝物阳性（LAC+）、IgG 抗心磷脂阳性（aCL+）、IgG 抗β(2)GPI 阳性（aβ(2)GPI+）]、15 名双重阳性患者（IgG aCL+，IgG aβ(2)GPI+）、9 名单一阳性患者（IgG aβ(2)GPI+）和 20 名对照者的血浆。
三重阳性患者的抑制百分比中位数为 25.5%（IQR17.2-33.0）。双阳性患者的抑制明显降低，抑制中位数为 5.0%（IQR0.0-27.0），单阳性患者的抑制中位数为 2.0%（IQR0.5-8.0）（p<0.0001）。在对照者或使用β(2)GPI 肽（40-52 和 57-70）时，或当使用抗凝血酶（一种不重要的对照蛋白）时，未检测到抑制。
与双阳性和单阳性患者相比，具有 APS 和三重实验室阳性的高风险患者具有更高的抗 DmI 抗体滴度，这通过抑制试验评估。
