Studies on target molecules for anti-endothelial cells autoantibodies detected in systemic vasculitis.

为了了解全身性血管炎的病理生理，识别和表征抗内皮细胞抗体（AECA）的自身抗原（autoAgs）是至关重要的，这种抗体在血管炎中经常被检测到。为此，我们使用了蛋白质组学方法。具体来说，我们分别从人脐静脉内皮细胞（HUVEC）和Hela细胞中提取蛋白质作为参比，通过二维电泳（2DE）分离蛋白质。然后，我们用western blotting（WB）检测了系统性血管炎患者血清样本中可识别的huvec特异性蛋白。此外，我们通过肽质量指纹图谱和MS/MS分析鉴定了AECA候选autoAgs。制备重组蛋白，探讨其临床意义。结果，我们检测到50个AECA候选autoag。其中一个鉴定的自ags是过氧化物还氧蛋白II（Prx II）。在接受检测的血管炎患者中，68%检测到Prx II的自身抗体（autoAbs），在患有胶原蛋白疾病但无明显血管炎的患者中检测到7.3%，在健康对照中检测到4.0%。临床上，Prx II自身抗体的存在与凝血酶-抗凝血酶复合物（TAT）和d -二聚体水平升高有关。此外，在HUVEC表面检测到Prx II。此外，Prxⅱ的自身抗体在大血管炎如主动脉炎综合征中经常被检测到。综上所述，我们通过蛋白质组学方法证明Prx II是AECA的靶点之一。Prxⅱ的自身抗体主要在血管炎疾病中检测到，将成为血管炎存在的新标志物。

To understand pathophysiology of systemic vasculitis, it would be critical to identify and characterize autoantigens (autoAgs) for the anti-endothelial cell antibody(AECA), which are detected frequently in vasculitis. For this aim, we used proteomics approaches. Specifically, we separated proteins extracted from human umbilical vein endothelial cells(HUVEC) and Hela cells as a reference respectively by 2-dimentional electrophoresis(2DE). We then detected HUVEC-specific proteins which were recognized by serum samples from patients with systemic vasculitis by western blotting(WB). Further, we identified the candidate autoAgs for AECA by peptide mass fingerprinting and the MS/MS analysis. Preparing recombinant proteins for the identified autoAgs, we investigated their clinical significance. As a result, we detected 50 candidate autoAgs for AECA. One of the identified autoAgs was peroxiredoxin II(Prx II). The autoantibodies (autoAbs) to Prx II were detected in 68% of the tested patients with vasculitis, 7.3% in tested patients with collagen diseases but no appearent vasculitis, and 4.0% in healthy controls. Clinically, presence of the autoAbs to Prx II was linked to the elevated levels of the thrombin-antithrombin complex(TAT) and D-dimer. In addition, Prx II was detected on the surface of HUVEC. Further, the autoAbs to Prx II were frequently detected in large-size vasculitis like aortitis syndrome. Taken, together, we demonstrated by the proteomic approach that Prx II is one of the targets of AECA. The autoAb to Prx II, detected predominantly in diseases with vasculitis, would be a new marker for presence of vasculitis.