Nalli Cecilia, Somma Valentina, Andreoli Laura, Büttner Thomas, Schierack Peter, Mahler Michael, Roggenbuck Dirk, Tincani Angela
University of Brescia, Brescia, Italy.
Research and Development Department, Medipan GmbH, Dahlewitz, Berlin, Germany.
Auto Immun Highlights. 2018 May 29;9(1):6. doi: 10.1007/s13317-018-0106-0.
Anti-phospholipid antibodies (aPL) analyzed by line immunoassay (LIA) can recognize beta-glycoprotein I (βGPI) domain 1 (D1) epitopes depending on βGPI binding to distinct phospholipids. The aPL LIA was compared with consensus ELISA to investigate whether both techniques can discriminate anti-phospholipid syndrome (APS) patients from aPL-positive, systemic autoimmune rheumatic diseases (SARD) patients without clinical symptoms of APS and controls.
Thirty-four APS patients (14 arterial/venous thrombosis, 16 pregnancy morbidity, and 4 both), 41 patients with SARD lacking clinical APS criteria but demonstrating positivity for anti-βGPI (aβGPI) IgG, and 20 healthy subjects (HS) were tested for aPL to cardiolipin (aCL), phosphatidic acid, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol (aPG), phosphatidylinositol, phosphatidylserine, βGPI, prothrombin, and annexin V by LIA. Samples were also tested for aCL, aβGPI, aβGPI-domain 1 (aD1), and aβGPI-domains 4-5 (aD4-5) by ELISA and for lupus anti-coagulant.
Comparison of LIA with ELISA revealed a good agreement for the consensus criteria aPL aβGPI and aCL IgG (kappa = 0.69, 0.68, respectively) and a moderate agreement for IgM (kappa = 0.52, 0.49, respectively). Regarding ELISA, aD1/aD4-5 demonstrated the best performance of differentiating APS from asymptomatic SARD [area under the curve (AUC): 0.76]. aPG IgG had the best performance by LIA (AUC: 0.72) not significantly different from aD1/aD4-5. There was a good agreement for aPG IgG with aD1/aD4-5 (kappa = 0.71).
aD1/aD4-5 (ELISA) and aPG IgG (LIA) differentiate APS from SARD patients. PG appears to interact with βGPI of APS patients and exposes D1 thereof for disease-specific aPL binding in LIA.
通过线性免疫测定（LIA）分析的抗磷脂抗体（aPL）可识别β-糖蛋白I（βGPI）结构域1（D1）表位，这取决于βGPI与不同磷脂的结合。将aPL LIA与共识ELISA进行比较，以研究这两种技术是否能够区分抗磷脂综合征（APS）患者与无APS临床症状的aPL阳性系统性自身免疫性风湿病（SARD）患者及对照。
对34例APS患者（14例动脉/静脉血栓形成、16例妊娠并发症、4例两者兼有）、41例缺乏临床APS标准但抗βGPI（aβGPI）IgG呈阳性的SARD患者以及20名健康受试者（HS）进行LIA检测，以检测其针对心磷脂（aCL）、磷脂酸、磷脂酰胆碱、磷脂酰乙醇胺、磷脂酰甘油（aPG）、磷脂酰肌醇、磷脂酰丝氨酸、βGPI、凝血酶原和膜联蛋白V的aPL。样本还通过ELISA检测aCL、aβGPI、aβGPI结构域1（aD1）和aβGPI结构域4 - 5（aD4 - 5），并检测狼疮抗凝物。
LIA与ELISA的比较显示，对于共识标准aPL aβGPI和aCL IgG，一致性良好（kappa值分别为0.69和0.68），对于IgM，一致性中等（kappa值分别为0.52和0.49）。关于ELISA，aD1/aD4 - 5在区分APS与无症状SARD方面表现最佳[曲线下面积（AUC）：0.76]。aPG IgG通过LIA表现最佳（AUC：0.72），与aD1/aD4 - 5无显著差异。aPG IgG与aD1/aD4 - 5一致性良好（kappa = 0.71）。
aD1/aD4 - 5（ELISA）和aPG IgG（LIA）可区分APS患者与SARD患者。PG似乎与APS患者的βGPI相互作用，并在LIA中暴露其D1以供疾病特异性aPL结合。
