Molecular cloning of eye muscle autoantigen in thyroid-associated ophthalmopathy.

有相当多的证据表明甲状腺相关眼病是一种自身免疫性疾病。然而，眼眶自身抗原(S)还没有完全阐明。我们以前报道过针对眼肌膜kDa蛋白的自身抗体的存在。本研究试图克隆和鉴定TAO患者的眼肌自身抗原(S)，用重型TAO患者的阳性血清筛选人骨骼肌c DNA文库，用猪眼肌kDa蛋白免疫的兔血清筛选人眼肌c DNA文库，但未得到阳性克隆。相反，从人眼肌肉文库中获得了4个阳性克隆(200-600bp)。其中一个片段(S13)经全自动DNA测序仪测序，鉴定为IgE结合蛋白。斑点印迹分析显示，20份TAO患者血清中有11份与融合蛋白反应，而6份对照中只有1份与融合蛋白反应。S13克隆与TAO的相关性尚不清楚。最近关于TAO患者眼肌组织中存在IgE以及变应性鼻炎发作后Graves病加重的报道支持了IgE结合蛋白可能在TAO的发生发展中起一定作用的观点。

There is considerable evidence that thyroid-associated ophthalmopathy is an autoimmune disorder. However, orbital autoantigen (s) has not been fully elucidated. We have previously reported the presence of autoantibodies against eye muscle membrane 64 kDa proteins. In the present study we attempted to clone and characterized the eye muscle autoantigen (s) in TAO.We screened human skeletal muscle cDNA library with positive sera from patients with severe TAO and human eye muscle cDNA library with the rabbit sera immunized with porcine eye muscle 64 kDa proteins.No positive clone was obtained from human skeletal muscle library. In contrast, 4 positive clones (200-600bp) were obtained from human eye muscle library. One of them (S13) was sequenced by automatic DNA sequencer and identified as an IgE binding protein. Dot blot study showed that 11 out of 20 sera from patients with TAO reacted with the fusion protein, whereas only one of 6 controls did.The relevance of S13 clone in TAO is not known. Recent reports on the presence of IgE in eye muscle tissue from patients with TAO and the exacerbation of Graves' disease after attack of allergic rhinitis support the notion that IgE binding protein may play some role in the development of TAO.