Investigation of the role of bacteria in the sarcoidosis trimolecular complex

结节病是一种病因不明的疾病，病理特征为非干酪化。 肉芽肿，最常见的累及肺、皮肤、淋巴结和眼睛。T细胞受体的研究进展 结节病患者的基因表达显示a(3+CD4+T细胞)寡克隆聚集在 肉芽肿性炎症，与抗原驱动的过程一致，受MHC限制。 结节病具有与分枝杆菌感染相似的病理、流行病学和免疫学特征。我们 对25例结节病和25例对照石蜡标本进行了16S rRNA、rpoB和S6110的聚合酶链式反应分析。 60%的结节样肉芽肿中有分支杆菌核酸的包埋标本和有记录的证据 也没有任何对照(P&lt；0.00002，卡方检验)。16S rRNA和rpoB扩增产物的序列分析 已发现的分枝杆菌核酸包括一种新的分枝杆菌，在遗传上类似于 结核分枝杆菌(MTB)(99%的位置一致性)。 最近的免疫学研究也表明，分枝杆菌可能在结节病中起重要作用。 免疫致病机制。Song等人在48%的人血清中发现了重组结核分枝杆菌katG抗体 结节病患者与PPD阴性对照组的血清中0%相比(p=0.0059)。使用矩阵辅助 激光解吸/电离飞行时间质谱仪，他们在75%的人中发现了MTB katG多肽 结节病标本与对照标本的比较(p=0.0006)；原位杂交定位 结节病肉芽肿内有MTB katG和16S rRNA DNA。最近，我们进行了酵素 联合免疫斑点(ELISPOT)检测结节病和控制外周血单核细胞 (PBMC)用于分枝杆菌katG和ESAT-6蛋白的免疫识别。我们发现了免疫识别 13例结节病患者中10例(77%)表达katG或ESAT-6多肽，而11例PPD阴性患者中1例表达katG或ESAT-6 健康对照组(9%)(p=0.001，Fisher‘s精确检验)和5个PPD阳性健康对照组中的4个(80%)(p=1.00， 费舍尔精确试验)。中心假说是结节病是一种免疫反应 遗传易感宿主中的分枝杆菌抗原。 结节病免疫致病的一个方面是成功地形成了一个三分子复合体。 T细胞受体(TCR)、主要组织相容性复合体(MHC)蛋白与加工 抗原。我们建议：1)确认和扩大分子遗传学证据的存在 分枝杆菌在结节病肉芽肿中的作用：2)表征T细胞对分枝杆菌抗原的反应 结节病患者中的急性、缓解和慢性病，以及3)确定它们之间的关系 与良好病程相关的人类白细胞抗原类型与免疫反应质量之间的关系 针对分枝杆菌抗原。

Sarcoidosis is a disease of unknown etiology, characterized pathologically by noncaseating granulomas which most commonly involve the lung, skin, lymph node and eyes. Studies of T cell receptor gene expression in sarcoidosis patients reveal oligoclonal collections of a(3+ CD4+ T cells at sites of granulomatous inflammation, consistent with an antigen-driven process which is MHC-restricted. Sarcoidosis has similar pathologic, epidemiologic, and immunologic features to mycobacterial infections. We performed PCR analysis for 16S rRNA, rpoB and \S6110 in 25 sarcoidosis and 25 control paraffin- embedded specimens and noted evidence of mycobacterial nucleic acids in 60% of the sarcoid granulomas and none of the controls (p<0.00002, chi square). Sequence analysis of the 16S rRNA and rpoB amplicons revealed mycobacterial nucleic acids including the presence of a novel Mycobacterium,genetically similar to M. tuberculosis (MTB) (99% positional identity). Recent immunologic studies also suggest that mycobacteria may be important in sarcoidosis immunopathogenesis. Song et al noted IgG antibodies to recombinant MTB katG in sera from 48% of sarcoidosis patients compared to 0% in sera from PPD negative controls (p=0.0059). Using matrix-assisted laser desorption/ionization time of flight mass spectrometry, they found MTB katG peptides in 75% of sarcoidosis specimens compared to 14% of control specimens (p=0.0006); in situ hybridization localized MTB katG and 16S rRNA DNA inside the sarcoidosis granuloma. More recently, we performed enzyme linked immunospot (ELISPOT) assays on sarcoidosis and control peripheral blood mononuclear cells (PBMC) for immune recognition of mycobacterial katG and ESAT-6 proteins. We found immune recognition of katG or ESAT-6 peptides in 10 of 13 sarcoidosis patients (77%) compared to 1 of 11 PPD negative healthy controls (9%)(p=0.001, Fisher's exact test) and 4 of 5 PPD positive healthy controls (80 %) (p=1.00, Fisher's exact test). The central hypothesis is that sarcoidosis is an immune response to mycobacterial antigens in a genetically susceptible host. One facet of sarcoidosis immunopathogenesis is the successful formation of a trimolecular complex between the T cell receptor (TCR), major histocompatibility complex (MHC) proteins and processed antigens. We propose to 1) confirm and extend molecular genetic evidence for the presence of mycobacteria in sarcoidosis granuloma, 2) to characterize the T cell response to mycobacterial antigens among sarcoidosis patients with acute, resolved, and chronic disease, and 3) to determine the relationship between HLA types associated with a favorable disease course and the quality of the immune response directed against mycobacterial antigens.