Role of Chemokines in Innate and Adaptive Immunity in the Lung

项目摘要 慢性铍病(CBD)是由工作场所接触铍(Be)引起的，其特征是 肉芽肿性炎症与BE特异性Th1型细胞因子分泌的CD4+T细胞的聚集 肺部。Be暴露还与诱导细胞因子/趋化因子分泌和协调 先天细胞和其他适应细胞向肺内募集。我们的初步数据显示，人类白细胞抗原DP2的暴露 转基因小鼠氧化应激(BeO)及对CBD来源的BAL细胞的刺激作用 BeSO4对CCL3和CCl4的分泌均有明显的诱导作用。重要的是，我们已经确定了相关的 来自CCL3和CCL4的被TCRs识别为BE依赖的新抗原的多肽 表达人类白细胞抗原DP2的慢性阻塞性肺疾病患者外周血中CD4+T细胞的变化BE负载的人类白细胞抗原-DP2-CCL3和 HL A-DP2-CCl_4四聚体染色显示，这些配体可被表达干扰素-γ的10-40%的人识别， BAL中BE特异性的CD4+T细胞，支持这些T细胞在BE诱导免疫中的重要性 回应。总而言之，我们的数据表明，先天介质CCL3和CCL4被分泌到肺中。 在被大部分BE特异性识别的关键T细胞表位作为靶点的同时响应BE CD4+T细胞。因此，在持续抗原暴露的背景下，我们假设BE诱导的CCL3和 CCl4分泌产生了先天和获得性免疫激活的破坏性循环，并耗尽了这些 带有基因工程T细胞的表位特异的CD4+T细胞将调节BE诱导的肺部炎症。 利用HLADP2TG小鼠，Aim 1将确定BeO诱导的CCL3和CCl4的细胞来源和作用 分泌物是肺部炎症的固有介质，而AIM 2将跟踪CCL3/BE-和 CBD小鼠模型中CCL4/BE特异性的CD4+T细胞。最终目标是利用嵌合抗原受体 (CAR)T细胞靶向表达HLA-DP2的小鼠和CBD患者的CD4+T细胞 治疗BE所致疾病的潜在治疗途径。拟议研究的意义 依赖于对趋化因子的新鉴定，这些趋化因子不仅与先天炎症细胞募集有关，而且还与 编码与人类白细胞抗原DP2结合的BE修饰的自体多肽，代表CBD中的主要T细胞表位。这个 成功完成这些研究，使用创新技术去除人类白细胞抗原表位特异性T细胞 表达DP2的小鼠和患有BE介导疾病的人将导致CAR T细胞作为一种潜在的 CBD的治疗选择，这是一种除了全身皮质类固醇之外几乎没有其他选择的疾病。

Project Summary Chronic beryllium disease (CBD) results from beryllium (Be) exposure in the workplace and is characterized by granulomatous inflammation and the accumulation of Be-specific, Th1-type cytokine-secreting CD4+ T cells in the lung. Be exposure is also associated with the induction of cytokine/chemokine secretion and the coordinated recruitment of innate and other adaptive cells to the lung. Our preliminary data show that exposure of HLA-DP2 Tg mice to Be oxide (BeO) as well as stimulation of bronchoalveolar lavage (BAL) cells derived from CBD patients with BeSO4 both induced significant CCL3 and CCL4 secretion. Importantly, we have identified related peptides derived from CCL3 and CCL4 that are recognized as Be-dependent neoantigens by TCRs expressed on CD4+ T cells derived from the BAL of HLA-DP2-expressing CBD patients. Be-loaded HLA-DP2-CCL3 and HLA-DP2-CCL4 tetramer staining showed that these ligands were recognized by 10-40% of IFN-γ-expressing, Be-specific CD4+ T cells in the BAL, supporting the importance of these T cells in the Be-induced immune response. Collectively, our data demonstrate that innate mediators, CCL3 and CCL4, are secreted into the lung in response to Be while also being targeted as key T cell epitopes recognized by a large fraction of Be-specific CD4+ T cells. Thus, in the setting of persistent antigen exposure, we hypothesize that Be-induced CCL3 and CCL4 secretion creates a destructive cycle of innate and adaptive immune activation and that depletion of these epitope-specific CD4+ T cells with genetically-engineered T cells will modulate Be-induced lung inflammation. Using HLA-DP2 Tg mice, Aim 1 will determine the cellular source and role of BeO-induced CCL3 and CCL4 secretion as innate mediators of lung inflammation while Aim 2 will track the dynamics of CCL3/Be- and CCL4/Be-specific CD4+ T cells in a murine model of CBD. The final aim will utilize chimeric antigen receptor (CAR) T cells to target epitope-specific CD4+ T cells in HLA-DP2-expressing mice and CBD patients as a potential therapeutic approach in the treatment of Be-induced disease. The significance of the proposed study rests on the novel identification of chemokines involved not only in innate inflammatory cell recruitment, but also encoding Be-modified self-peptides that bind to HLA-DP2 and represent dominant T cell epitopes in CBD. The successful completion of these studies using innovative technology to deplete epitope-specific T cells in HLA- DP2-expressing mice and humans with Be-mediated disease will lead to the potential use of CAR T cells as a therapeutic option for CBD, a disease with few alternatives to systemic corticosteroids.