T cell epitopes in sarcoidosis

项目摘要 结节病是一种病因不明的全身性肉芽肿性疾病，对肺部的影响大于 90%的病例。这种疾病的特点是活化的CD4+T细胞在肺和其他组织中积聚 疾病活动的地点。有证据表明，这些T细胞与糖尿病的发病密切相关。 结节病。在一种称为L综合征的急性结节病中， 表达T细胞受体α的肺CD_4~+T细胞的HLADRB1*03：01等位基因和扩增 已观察到链可变(V)区Vα2.3。这些T细胞群本质上是寡克隆的， 表明它们对常规抗原的反应被重新聚集到肺中。此外，这些T细胞 扩张被分割到肺，随着疾病的缓解而消失，强调了他们的 在疾病发病机制中的重要性。我们推测，在人类白细胞抗原-DRB1*03：01患者中，患有L 综合征，表达VCD42.3的α+T细胞克隆在肺内积聚和扩张 病原性结节病抗原，并以限制的方式识别该抗原-HLADRB1*03：01。这 该提案利用了一个国际研究团队的优势，并专注于一组不同的人类白细胞抗原- 1*03：01+瑞典L综合征患者 已知的三分子复合体(即HLADRB1*03：01和VCD42.3表达α+T细胞)。使用单个 细胞RT-PCR法，AIM 1将表征在表达αβ+Vα2.3T细胞上表达的CD4TCR对 在L综合征患者的BAL中，并产生表达感兴趣的TCR的杂交瘤。这个 第二个特定目标将确定刺激表达疾病的CD4+T细胞杂交瘤的多肽- 相关TCR来源于L综合征患者。最终目标是使用人类白细胞抗原-DR3-多肽四聚体 鉴定结节病患者肺中抗原特异性的CD4+T细胞，并确定其频率是否 这些T细胞可作为诊断和预后的生物标志物。因此，使用创新和新颖 技术，我们将解决病因性T细胞抗原中的关键知识空白，这些抗原参与启动 L综合征患者的疾病，进一步加深了我们对其发病机制的认识 疾病。此外，这些结果将为美国对结节病的进一步研究奠定基础。

Project Summary Sarcoidosis is a systemic granulomatous disorder of unknown etiology which affects the lung in greater than 90% of cases. The disease is characterized by the accumulation of activated CD4+ T cells in the lung and other sites of disease activity. Evidence suggests that these T cells are intimately involved in the pathogenesis of sarcoidosis. In an acute form of sarcoidosis known as Löfgren’s syndrome, a correlation between the presence of the HLA-DRB1*03:01 allele and expansions of lung CD4+ T cells expressing the T cell receptor (TCR) α- chain variable (V) region Vα2.3 has been observed. These T cell populations are oligoclonal in nature, suggesting their recruitment to the lung in response to conventional antigen. In addition, these T cell expansions are compartmentalized to the lung and disappear with disease remission, underscoring their importance in disease pathogenesis. We hypothesize that in HLA-DRB1*03:01 individuals with Löfgren’s syndrome, Vα2.3-expressing CD4+ T cell clones accumulate and expand in the lungs in response to the etiologic sarcoidosis antigen and recognize that antigen in an HLA-DRB1*03:01-restricted fashion. This proposal harnesses the strengths of an international research team and focuses on a distinct cohort of HLA- DRB1*03:01+ Swedish subjects with Löfgren’s syndrome in which two of the three components of the trimolecular complex are known (i.e., HLA-DRB1*03:01 and Vα2.3-expressing CD4+ T cells). Using a single cell RT-PCR approach, Aim 1 will characterize the αβTCR pairs expressed on CD4+ Vα2.3-expressing T cells in the BAL of Löfgren’s syndrome patients and generate hybridomas expressing the TCRs of interest. The second specific aim will determine the peptides that stimulate the CD4+ T cell hybridomas expressing disease- relevant TCRs derived from Löfgren’s syndrome patients. The final aim will use HLA-DR3-peptide tetramers to identify antigen-specific CD4+ T cells in the lungs of sarcoidosis patients and determine if the frequency of these T cells can serve as a biomarker for diagnosis and prognosis. Thus, using innovative and novel technology, we will address critical knowledge gaps in the etiologic T cell antigens involved in the initiation of disease in patients with Löfgren’s syndrome, further advancing our understanding of the pathogenesis of this disease. In addition, these results will lay the foundation for additional studies of sarcoidosis in the US.