Development &validationof a panel of antibodies for the diagnosis of sarcoidosis

描述（由申请人提供）：该提案将验证免疫在结节病发病机制中起重要作用的假设，如免疫功能异常和抗体的存在，包括在该疾病中发现的类风湿因子和抗核抗体。此外，结节病与其他全身性炎症性疾病共存，患者常表现为皮肤能量不足和高γ球蛋白血症。我们建议开发一组具有高灵敏度和特异性的抗体/自身抗体来识别结节病患者，并有助于将这些患者与对照组和其他肺部疾病患者区分开来。为此，我们将利用从结节病患者患病淋巴结组织中分离的mRNA构建潜在结节病抗原的T7噬菌体cDNA文库。该cDNA文库将与含有高滴度IgG抗体的结节病患者血清进行免疫筛选，克隆的菌落将用于构建抗原微阵列，并与肺结节病患者和对照组的血清杂交。对照血清将从血清阳性的类风湿关节炎患者和有结核病史的患者中获得。对结节病患者血清识别为抗原的信息噬菌体插入物进行序列分析，可以识别与结节病发病相关的抗原。自身抗体分类器将用独立采集的病例和对照血清进行验证。在未来，这种方法可能会确定对结节病治疗有用的分子靶点。

DESCRIPTION (provided by applicant): This proposal will test the hypothesis that immunity has a prominent role in the pathogenesis of sarcoidosis, as suggested by abnormalities of the immune function and by the presence of antibodies, including rheumatoid factors and antinuclear antibodies found in this disorder. In addition, sarcoidosis coexists with other systemic inflammatory diseases, and patients frequently show cutaneous anergy and hypergammaglobulinemia. We propose to develop a panel of antibodies/autoantibodies with high sensitivity and specificity to identify patients with sarcoidosis and help to distinguish these patients from controls and individuals with other pulmonary diseases. For this purpose we will construct a T7 phage cDNA library of potential sarcoidosis antigens using mRNA isolated from affected lymph node tissue of patients with sarcoidosis. This cDNA library will be immunoscreened with sera from patients with sarcoidosis containing high titer IgG antibodies and the cloned colonies will be used to construct an antigen microarray that will be hybridized with sera from cases with lung sarcoidosis and controls. Control sera will be obtained from patients with sero-positive rheumatoid arthritis and from patients with a history of tuberculosis. Sequence analyses of informative phage inserts recognized as antigens by sarcoidosis patient sera may identify antigens associated with the etiopathogenesis of sarcoidosis. The autoantibody classifier will be validated with independently obtained collections of sera from cases and controls. In the future, this approach may identify molecular targets useful for the treatment of sarcoidosis. PUBLIC HEALTH RELEVANCE: Aberrant immune responses are a major cause of a vast array of human diseases. Sarcoidosis is an inflammatory disease of unknown etiology sharing similarities with many inflammatory or granulomatous diseases such as Crohn's disease, rheumatoid arthritis, and lupus erythematosus. Sarcoidosis occurs throughout the world with an average incidence of 16.5/100,000 in men and 19/100,000 in women but up to 75/100,000 in African-Americans. Due to its chronicity and to its tendency to affect young individuals, it has high impact on the health and economy in our society. Since the description of this condition more than a century ago, studies have failed to identify specific antigens leading to granulomatous inflammation in sarcoidosis. The proposed studies will identify a panel of antibodies recognizing sarcoidosis granuloma antigens. This will be useful as a tool to diagnose pulmonary sarcoidosis and may identify molecular targets for the treatment of this disease. The main delivery from this project will be a diagnostic instrument useful in a clinical setting for the diagnosis of pulmonary sarcoidosis. Characterization of informative phage may reveal the presence of antigens from bacterial or viral antigens related to the development of pulmonary sarcoidosis. A long term objective of this proposal is the identification of organ-specific antigens which could be targeted by drugs or be the basis for immunotherapy.