Regulation of Type I IFNs in Tolerance and Autoimmunity

项目摘要/摘要： 干扰素-a在先天性和获得性免疫调节中起着关键作用。 免疫反应，主要通过激活树突状细胞(DC)。异常激活 DC可能会将自身AGS的表现从耐受性转变为自身免疫性，实际上是过度的 对干扰素-a的应答被认为是狼疮等自身免疫性疾病的致病因素。 我们的长期目标是发现能够抑制DC和 确定它们对自身免疫性疾病发展的影响。我们最近的研究表明 IL-4在体外和体内均抑制DC对干扰素-α的应答。我们建议调查 IL-4抑制对干扰素-a的先天反应的分子机制 对适应性免疫反应的影响。此外，我们还发现了这块骨头 狼疮易感小鼠骨髓来源的DC具有固有的I型干扰素高活性 IL-4抑制的反应，我们打算确定IL-4作为治疗的潜力。 狼疮。在目标I中，我们将确定IL-4抑制作用的分子机制 关于干扰素的反应。我们假设IL-4作用于影响第一反应的分子 旁分泌干扰素-a/b和自分泌干扰素诱导的正反馈环。基于我们的 关于IL-4的初步研究和现有文献，我们假设一种新的IL-4诱导的 蛋白质抑制1)STAT1-2的磷酸化或2)干扰素的转录 基因(ISG)，如干扰素-a/b。我们将解决IL-4R下游的哪条信号通路 介导IL-4抑制干扰素应答，是什么机制阻断了STAT1-2 IL-4抑制IL-4过程中的磷酸化及其阻断干扰素-b转录的机制 干扰素应答。在AIM II中，我们将测试IL-4对两种获得性免疫的刺激作用 体内干扰素-α、交叉激发和同型抗体转换刺激的应答。在AIM III中，我们 将确定针对DC的IL-4在狼疮自身免疫发展中的作用。我们 将使用两种方案：a)注射携带IL-4的慢病毒转导的DC，以及b) 用相同的慢病毒转导的骨髓祖细胞移植，并将比较 全身应用IL-4治疗的疗效及不良反应 效果。这个项目将阐明通过以下方式调节先天和适应性反应 细胞因子及其作为治疗系统性红斑狼疮新策略的潜力。 此外，我们将测试两种新的针对DC的基因转移协议，这两种协议可能有助于 传递免疫调节和诱导自身免疫耐受的候选基因 移植。

PROJECT SUMMARY/ABSTRACT: Interferon alpha (IFN-a) is a pivotal player in the regulation of the innate and the adaptive immune responses, primarily through the activation of dendritic cells (DCs). Abnormal activation of DCs may shift the presentation of self-Ags from tolerance to autoimmunity and, indeed, excessive responses to IFN-a have been proposed to be pathogenic in autoimmune diseases such as lupus. Our long-term goal is to discover biologic factors able to inhibit the response to IFN-a in DCs and determine their effects on the development of autoimmune diseases. Our recent studies indicate that IL-4 suppresses the response of DCs to IFN-a in vitro and in vivo. We propose to investigate the molecular mechanisms by which IL-4 inhibits the innate response to IFN-a and the consequences on the adaptive immune responses. Furthermore, we have found that bone marrow-derived DCs from lupus-prone mice have an intrinsic hyperactivation of the Type I IFN response that is inhibited by IL-4 and we intend to determine the potential of IL-4 as therapy in lupus. In Aim I, we will determine the molecular mechanisms underlying IL-4 suppressive effects on IFN responses. We hypothesize that IL-4 acts on molecules that affect both the first response to paracrine IFN-a/b and the positive feedback loop induced by autocrine IFNab. On the basis of our Preliminary Studies and available literature on IL-4, we hypothesize that a newly IL-4-induced protein inhibits either 1) the phosphorylation of STAT1-2 or 2) the transcription of IFN stimulated genes (ISG) such as IFN-a/b. We will address which signaling pathway, downstream of IL-4R, is mediating IL-4 suppression of IFN response, which mechanism is blocking the STAT1-2 phosphorylation and which mechanism is blocking IFN-b transcription during IL-4 suppression of IFN response. In Aim II, we will test the effects of IL-4 on the stimulation of two adaptive immune responses stimulated by IFN-a, cross-priming and isotype antibody switching in vivo. In Aim III, we will determine the effects of IL-4 targeted to DCs on the development of lupus autoimmunity. We will use two protocols: a) injection of DCs transduced with a lentivirus carrying IL-4, and b) transplantation of bone marrow progenitors transduced with the same lentivirus, and will compare them with systemic administration of IL-4, in terms of therapeutic efficacy and development of side effects. This project will shed light on the regulation of the innate and adaptive responses by cytokines and their potential as novel therapeutic strategy to cure systemic lupus erythematosous. In addition, we will test two novel protocols of gene transfer targeting DCs that may be useful to deliver candidate genes for immune-modulation and induction of tolerance in autoimmunity and transplantation.