The Role of Estrogen Receptor Alpha Variant Size and Localization in Modulating TLR7-Induced Inflammation

系统性红斑狼疮(SLE)是多种自身免疫性疾病之一。 女性。尽管发现了许多狼疮的危险因素：包括GPR174在内的170个基因，无数 环境暴露和X染色体的异常失活，这些都不能充分解释陡峭的 青春期广告的发生率以女性特有的方式上升。流行病学表明， 自身免疫性疾病中的性激素及其受体。我们之前的研究表明，女性容易患狼疮 只表达一种短形式雌激素受体α(ERαShort)的小鼠，肾脏显著减少 疾病和增加的存活率。确定这种保护作用的机制，即雌激素 依赖，是这项提议的主要目标。值得注意的是，ERα-/-(零)狼疮易感小鼠不是类似的 受到保护。总而言之，我们的数据表明，简称ERα的存在提供了保护，而不是 缺少全长ERα。其他人和我们展示了ERα在树突状细胞(DC)发育中的关键作用 和内体Toll样受体(TLR)反应性。有趣的是，ERα在ERα短小鼠中表达 在结构上类似于内源性ERα变异体(ERα46)，它缺乏相同的AF-1结构域，但不同 与全长ERα相比，它调节基因转录。体外过表达ERα46也调节TLR46- 与这项提议相关的诱导反应。在拟议的研究中，我们将进一步研究ERα的作用 在调节TLR7诱导的免疫反应中的短变体，并确定基因组和/或非基因组 ERα短变异作用的基因组机制是保护性的。我们的总体假设是不断增加的 ERαShort或ERα46在免疫细胞中的表达具有抗炎作用，ERα46的比例 与健康对照组相比，狼疮患者的TO ERα66降低。我们还假设目标是 新型抗炎选择性雌激素受体调节剂(SERM)可改变ERα的免疫细胞 膜信号转导和/或ERα诱导的转录将解偶联雌激素介导的抗炎 来自那些影响生殖组织的反应。我们将通过实现这些来检验我们的假设 具体目标：1)过表达ERα短或用新型SERM(OBHS，PAPE)治疗免疫细胞 ERα的抗炎特性，并确定其对已知TLR7诱导的炎症终点的影响， 2)研究单膜型ERα信号转导与核型ERα表达在TLR7诱导中的作用 3)鉴定人单核细胞来源的树突状细胞(mo-DC)和B细胞中的ERα变异体 应用Droplet数字聚合酶链式反应和等位基因序列技术检测ERα46在乳腺癌中的表达 狼疮患者与对照组相比，潜在地解释了易患自身免疫的女性在生物学上的差异。 这些目标将使我们能够确定是否可以将ERα的S生殖影响与其潜在的可变性分开 免疫效应作为一种治疗策略，如果成功，将提供新的免疫方法 调节狼疮和其他免疫介导性疾病，特别是那些有明显性别偏见的疾病。

Systemic lupus erythematosus (SLE) is one of many autoimmune diseases that disproportionately affects females. Although many risk factors for lupus are identified: >170 genes including GPR174, myriad environmental exposures, and aberrant X chromosome inactivation, none of these sufficiently explain the steep rise in incidence of ADs at the time of puberty in a female-specific manner. Epidemiology suggests a major role for sex hormones and their receptors in autoimmune diseases. We previously showed that female lupus-prone mice, expressing only a short form of estrogen receptor alpha (ERα short), have significantly reduced renal disease and increased survival. Determining the mechanism of this protective effect, which is estrogen dependent, is the primary goal of this proposal. Of note, ERα-/- (null) lupus prone mice were not similarly protected. Combined, our data suggest that the presence of the short form of ERα confers protection, not the absence of full-length ERα. Others and we demonstrated a critical role for ERα in dendritic cell (DC) development and endosomal Toll-like receptor (TLR) responsiveness. Interestingly, the ERα expressed in ERα short mice is similar in structure to an endogenous ERα variant (ERα46) that lacks the same AF-1 domain, and differentially regulates gene transcription compared to full length ERα. Overexpressing ERα46 in vitro also modulates TLR- induced responses, relevant to this proposal. In the proposed study, we will further investigate the role of ERα short variants in modulating TLR7-induced immune responses, and determine whether genomic and/or non- genomic mechanisms of ERα short variant action are protective. Our overall hypothesis is that increasing expression of ERα short or ERα46 in immune cells will be anti-inflammatory, and that the ratio of ERα46 to ERα66 is decreased in lupus patients versus healthy controls. We also hypothesize that targeting immune cells with novel anti-inflammatory selective estrogen receptor modulators (SERMs) that alter ERα membrane signaling and/or ERα-induced transcription will uncouple estrogen-mediated anti-inflammatory responses from those impacting reproductive tissues. We will test our hypotheses by accomplishing these Specific Aims: 1) Overexpress ERα short or treat immune cells with novel SERMs (OBHS, PaPE) that select for anti-inflammatory properties of ERα and determine the effect on known TLR7-induced inflammatory endpoints, 2) Investigate effects of membrane-only ERα signaling vs. nuclear only ERα expression on TLR7-induced pathways in mice, and 3) Identify ERα variants in human monocyte-derived dendritic cells (mo-DCs) and B cells using droplet digital PCR and Iso-Seq technology, to determine whether ERα46 is differentially expressed in lupus patients vs. controls, potentially explaining a biologic difference in females predisposed to autoimmunity. These aims will allow us to determine if we can separate ERα's reproductive effects from its potentially modifiable immune effects as a therapeutic strategy, which if successful, will provide novel approaches to immune modulation in lupus and other immune mediated diseases, especially those with a significant sex bias.