Identification of citrullinated alpha-enolase as a candidate autoantigen in rheumatoid arthritis.
Identification of citrullinated alpha-enolase as a candidate autoantigen in rheumatoid arthritis.
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DOI：
10.1186/ar1845
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发表时间：
2005
影响因子：
4.9
通讯作者：
Venables, Patrick J
中科院分区：
文献类型：
--
作者：
Kinloch, Andrew;Tatzer, Verena;Wait, Robin;Peston, David;Lundberg, Karin;Donatien, Phillipe;Moyes, David;Taylor, Peter C;Venables, Patrick J
抗瓜氨酸化蛋白的抗体对类风湿性关节炎（RA）具有高度特异性，但对其瓜氨酸化靶抗原了解甚少。我们已经检测到一个候选瓜氨酸化蛋白免疫印迹处理的单核细胞和粒细胞HL-60细胞的裂解液肽酰精氨酸脱亚胺酶。在对来自四名RA患者和一名对照的血清样品的初始筛选中，来自单核细胞HL-60的分子量为47 kDa的蛋白质与来自患者的血清反应，但不与来自对照的血清反应。只有瓜氨酸形式的蛋白质被识别。通过串联质谱鉴定抗原为α-烯醇化酶，并确定序列中9个瓜氨酸残基的位置。采用免疫印迹法检测52例RA患者和40例健康对照者血清中抗瓜氨酸化和非瓜氨酸化α-烯醇化酶抗体的存在。24份RA患者血清（46%）与瓜氨酸化α-烯醇化酶反应，其中7份（13%）还识别非瓜氨酸化蛋白。来自对照品的6份样品（15%）与两种形式反应。在RA关节中检测到α-烯醇化酶，与瓜氨酸化蛋白共定位。关节内抗体的存在和抗原的表达表明瓜氨酸化α-烯醇化酶是一种候选的自身抗原，可以驱动RA的慢性炎症反应。
Antibodies against citrullinated proteins are highly specific for rheumatoid arthritis (RA), but little is understood about their citrullinated target antigens. We have detected a candidate citrullinated protein by immunoblotting lysates of monocytic and granulocytic HL-60 cells treated with peptidylarginine deiminase. In an initial screen of serum samples from four patients with RA and one control, a protein of molecular mass 47 kDa from monocytic HL-60s reacted with sera from the patients, but not with the serum from the control. Only the citrullinated form of the protein was recognised. The antigen was identified by tandem mass spectrometry as α-enolase, and the positions of nine citrulline residues in the sequence were determined. Serum samples from 52 patients with RA and 40 healthy controls were tested for presence of antibodies against citrullinated and non-citrullinated α-enolase by immunoblotting of the purified antigens. Twenty-four sera from patients with RA (46%) reacted with citrullinated α-enolase, of which seven (13%) also recognised the non-citrullinated protein. Six samples from the controls (15%) reacted with both forms. α-Enolase was detected in the RA joint, where it co-localised with citrullinated proteins. The presence of antibody together with expression of antigen within the joint implicates citrullinated α-enolase as a candidate autoantigen that could drive the chronic inflammatory response in RA.