Interferon Beta Initiated Development of Immunogenic T1 B cells in Lupus

系统性红斑狼疮(SLE)是一种慢性衰弱疾病，其特征是高滴度的 具有核自身抗原特异性的自身抗体。它被认为是由以下因素相互作用而产生的 潜在的遗传易感性和环境因素，不同的组合导致相互作用 疾病表现和治疗反应的个体差异。定向治疗靶向 对特定途径的研究尚未被证明有效，这表明目前对发病机制的理解 是不完整的。被提议的项目的目标是检验这样一种假设，即幼年动物的生存 自身反应性B细胞、抗核自身反应性B细胞的优先发展和成熟状态 自身反应性B细胞(免疫活性与无能/耐受性)在过渡期1(T1)中决定。 并要求组成的T1 B细胞表达干扰素β(干扰素β)。 这一范式转换假设是基于使用混合骨髓组合产生的数据 嵌合体、四聚体或独特型抗体选择的流式细胞术，以及高通量单细胞分析 [目的]探讨系统性红斑狼疮(SLE)患者和狼疮易感Bxd2小鼠B细胞中I型干扰素(IFN)网络。这个 数据表明，目前已知的分子和细胞像差之前有一个单一的原生体 致病事件，即T1 B细胞产生干扰素β。数据表明，极早期T1的存活率 细胞依赖内源性干扰素β的表达。这个亚群的T1 B细胞表达内源性干扰素β， 这会导致它们发育成分泌干扰素α的T1 B细胞。T1 B细胞逃避负性免疫反应的能力 B细胞受体(BCR)介导的选择由I型干扰素决定的这个T1的反应性决定 BCR介导的信号与刺激TLR信号(TLR7或TLR9)的子集 细胞凋亡性碎片。这优先允许核抗原自身反应的B细胞逃逸。我们还有更多 确定T1 B细胞室包含不同的细胞亚群。因为这些子集包括 与成熟和无能抑制调节(BREG)细胞表型平行的转录图谱 和它们在SLE中占主导地位的免疫原性对应物，我们的新数据表明，这种表型转换 在成熟的B细胞中，在T1期有印记。这些数据还表明，I型干扰素的发展 Bxd2小鼠网络相关T1 B细胞与I型干扰素诱导转录因子(IRF3)相关 和IRF7)，而Foxp3+调节性T1 B细胞的诱导与转录因子ID3有关。 值得注意的是，这些数据不仅表明抑制T1-Breg前体是一种新的致病因素 框架，但也提供了工具，即在分类的过渡性B细胞中的基因表达特征， 这使得它的分析成为可能。我们将通过三个具体目标来测试我们总体假设的关键要素 这将：(1)区分组成性干扰素β信号和微环境信号在 推动T1 B细胞的发育；(2)确定最初的T1 B细胞转录印记是否保持不变 在T2/MZP-MZ-FO发育阶段；以及(3)确定T1 B细胞内源性干扰素β是否促进一种类型 抑制SLE患者T1期调节性B细胞前体的干扰素网络。这个 拟议工作的科学前提包括T1 B细胞转录图谱之间的相似性 和成熟B细胞以及I型干扰素相关和BREG相关转录图谱的分离 T1B细胞。我们已经获得了干扰素β、IL-10、foxp3和id3的报告小鼠品系来询问Discreet 过渡性T1 B亚集内及其派生的发育阶段。 所获得的信息将对现场产生广泛的影响，并改善VA患者的护理 通过确定策略来提高靶向生物治疗的疗效，并与非 侵入性精确医学引导入路。

Systemic lupus erythematosus (SLE) is a chronic debilitating disease that is characterized by high titers of autoantibodies with specificity for nuclear autoantigens. It is considered to arise from interactions between underlying genetic susceptibility and environmental factors, with different combinations resulting in inter- individual variations in disease manifestations and therapeutic responsiveness. Directed therapeutic targeting of specific pathways has not proven effective, which suggests that the current understanding of pathogenesis is incomplete. The goal of the proposed project is to test the hypothesis that the survival of immature autoreactive B cells, the preferential development of antinuclear autoreactive B cells and the status of mature autoreactive B cells (immunocompetent vs. anergic/tolerogenic) is decided during the transitional stage 1 (T1) of development and requires constitutive T1 B cell expression of interferon β (IFNβ). This paradigm shifting hypothesis is based on data generated using a combination of mixed-bone marrow chimeras, flow cytometry with tetramer or idiotype antibody selection, and high-throughput single-cell analysis to interrogate type I interferon (IFN) networks in B cell from patients with SLE and lupus-prone BXD2 mice. The data suggest that the currently known molecular and cellular aberrations are preceded by a single primary pathogenic event, i.e., production of IFNβ by T1 B cells. The data suggest that the survival of the very early T1 cells is dependent on endogenous expression of IFNβ. This subset of T1 B cells express endogenous IFNβ, which leads to their development into T1 B cells that produce IFNα. The ability of T1 B cells to escape negative B-cell receptor (BCR)-mediated selection is dictated by the type I IFN-determined responsiveness of this T1 subset to BCR-mediated signaling in combination with stimulation of TLR signaling (TLR7 or TLR9) by apoptotic debris. This preferentially permits escape of nucleic antigen-autoreactive B cells. We have further identified that the T1 B cell compartment contains distinct subsets of cells. As these included subsets with transcriptional profiles that parallel the phenotypes of mature and anergic suppressive regulatory (Breg) cells and their immunogenic counterparts that predominate in SLE, our new data suggest that this phenotypic switch in the mature B cells is imprinted during the T1 stage. These data also suggest that development of type I IFN network associated T1 B cells in BXD2 mice is associated with type I IFN-inducing transcription factors (IRF3 and IRF7) whereas induction of the Foxp3+ regulatory T1 B cells is associated with transcription factor, ID3. Notably, these data not only suggest suppression of precursors of T1-Breg is a novel pathogenic framework in SLE but also provide the tool, i.e., the gene expression signatures in sorted transitional B cells, that enable its analysis. We will test the critical elements of our overall hypothesis through three Specific Aims that will: (1) Distinguish the roles of the constitutive IFNβ signaling and the microenvironmental signals in driving the development of T1 B cells; (2) Identify if the initial T1 B cell transcriptional imprinting is maintained at the T2/MZP-MZ-FO stage of development; and (3) Determine if T1 B-cell endogenous IFNβ promotes a type I IFN network that suppresses the precursors of regulatory B cells at the T1 stage in SLE patients. The scientific premises of the proposed work include the parallels between transcriptional profiles in the T1 B cells and mature B cells and the segregation of type I IFN associated vs Breg associated transcriptional profiles in the T1 B cells. We have acquired reporter mouse strains for IFNβ, IL-10, Foxp3 and Id3 to interrogate discreet developmental stages within and derived from transitional T1 B subsets. The information gained will have a broad-based impact on the field and improve the care of VA patients with SLE by identifying strategies to improve the efficacy of targeted biologic therapies together with non- invasive precision medicine guided-approaches.