Pathogenesis of Fever in Man

项目总结/摘要 白细胞介素-38（IL-38）是白细胞介素-1家族的一员，尽管其被发现，但直到最近才被研究 20年前它是一种被忽视的细胞因子，因为没有识别出IL-38如何起作用的受体。 然而，在2012年，我们报道了重组人IL-38与IL-36受体（现在的IL-1 R6）结合， 抑制IL-17和IL-22的产生。在该研究中，我们提出IL-38作为受体， IL-1 R6的拮抗剂。然而，IL-38的剂量反应并不表现为受体拮抗剂，而是 作为细胞活性的抑制剂。新的数据表明，IL-38需要IL-1 R6，一种孤儿受体， IL-1家族，以抑制IL-17。IL-1 R9以前被称为IL-1受体相关蛋白样-1， 研究其在重组IL-38抑制先天免疫中的假定作用。使用CRISPR/Cas 方法，我们已经产生了一群缺乏IL-38的小鼠。这些老鼠被用来确定 在人类炎症性疾病的小鼠模型中需要内源性IL-38。在这些模型中 当IL-38缺陷小鼠的疾病严重程度降低时，我们将使用重组IL-38治疗小鼠， 抑制先天性炎症。为了充分了解IL-38在先天免疫中的作用，我们 产生IL-1 R9缺陷的小鼠集落。我们将研究IL-1 R9对IL-1 R9功能的需求， 在用IL-38治疗显著降低疾病的那些小鼠模型中， 严重性。该应用的一个独特方面是IL-1 R9位于X染色体上，这是在X染色体上的一个不寻常的发现。 细胞因子生物学由于IL-1 R9位于X染色体上，我们可以解决先天性IL-1 R9抑制是如何发生的。 与女性相比，男性的免疫力受到影响。大多数自身免疫性疾病有70%的 女性的偏好，每种自身免疫性疾病都有炎症的贡献，我们有 设计研究，用于比较纯合IL-1 R9缺陷男性与纯合IL-1 R9女性。 在这些研究中，我们还将评估IL-38抑制NLRP 3炎性体活化的作用 使用目前用于治疗患者的特异性口服NLRP 3抑制剂。除了AIM 1和AIM 2研究外， 关于重组IL-38对先天免疫的抑制作用和IL-1 R9的假定作用，我们将生产和 检测IL-38-Fc融合蛋白（AIM 3）。产生IL-38-Fc融合蛋白的基本原理是提供 IL-38治疗剂的临床前数据。在AIM 4中，我们解决了IL-38从细胞释放的问题。IL-38 在健康受试者中循环，但在有心血管事件风险的受试者中水平显著低。 然而，IL-38是一种B细胞产物，这表明IL-38前体的加工和从B细胞中的释放与IL-38的表达有关。 细胞不是通过传统途径。我们将检查其他成员使用的分泌途径 IL-1家族：抑制NLRP 3和抑制钙蛋白酶。这些研究的总体目标是 推进IL-38的生物学和临床意义，以及开发抗炎特性， IL-38作为治疗剂。

Project Summary/Abstract Interleukin-38 (IL-38), a member of the IL-1 family, has not been studied until recently despite its discovery 20 years ago. It is a neglected cytokine because no receptor was identified for how IL-38 functioned. However, in 2012, we reported that recombinant human IL-38 bound to the IL-36 receptor (now IL-1R6) and suppressed the production of IL-17 and IL-22. In that study, we proposed that IL-38 acted as a receptor antagonist for IL-1R6. However, the dose-response of IL-38 did not behave as receptor antagonist but rather acted as an inhibitor of cell activities. New data suggests that IL-38 requires IL-1R6, an orphan receptor in the IL-1 Family, to suppress IL-17. Formerly termed IL-1 Receptor Associated Protein Like-1, IL-1R9 will be studied for its putative role in the suppression of innate immunity by recombinant IL-38. Using CRISPR/Cas methods, we have generated a colony of mice that are deficient in IL-38. These mice are used to determine a requirement for endogenous IL-38 in mouse models of human inflammatory diseases. In those models where disease severity worsens in IL-38 deficient mice, we will use recombinant IL-38 to treat mice for suppression of innate inflammation. In order to fully understand the role of IL-38 in innate immunity, we generated a mouse colony deficient in IL-1R9. We will study the requirement of IL-1R9 for the function of recombinant IL-38 in those mouse models where treatment with IL-38 has significantly reduced disease severity. A unique aspect of this application is that IL-1R9 in on the X-chromosome, an unusual finding in cytokine biology. Because IL-1R9 is on the X-chromosome, we can address how suppression of innate immunity is affected in males compared to females. With most autoimmune diseases having a 70% predilection for females and with each autoimmune disease there is an inflammatory contribution, we have designed studies for comparisons of homozygous IL-1R9 deficient males to homozygous IL-1R9 females. In these studies, we will also evaluate the role of IL-38 to inhibit the activation of the NLRP3 inflammasome using a specific oral NLRP3 inhibitor presently used to treat patients. In addition to AIM 1 and AIM 2 studies on recombinant IL-38 suppression of innate immunity and the putative role of IL-1R9, we will produce and test an IL-38-Fc fusion protein (AIM 3). The rationale for producing an IL-38-Fc fusion protein is to provide pre-clinical data for an IL-38 therapeutic. In AIM 4 we address the issue of IL-38 release from the cell. IL-38 circulates in healthy subjects but levels are significantly low in subjects at risk for a cardiovascular events. However, IL-38 being a B-cell product suggests that processing of the IL-38 precursor and release from the cell is not via traditional pathways. We will examine pathways for secretion that are used by other members of the IL-1 Family : inhibition of NLRP3 and inhibition of calpains. The overall goal of these studies is to advance the biology and clinical significance of IL-38 as well as to exploit the anti-inflammatory properties of IL-38 as a therapeutic.