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

点击翻译按钮获取中文摘要

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.