IL-10 Receptor Signaling That Regulates Innate Immunity

描述（由申请人提供）：IL-10是一种对免疫系统功能有不同影响的细胞因子。它通过增强B细胞的增殖、存活和分化来促进体液免疫，但通过抑制来自骨髓细胞和淋巴细胞的促炎细胞因子的产生来抑制先天免疫。il -10通过与许多不同免疫细胞上表达的特定受体结合来显示其作用。我们之前的工作有助于定义IL-10受体，并证明JAK-STAT信号通路是所有IL-10受体刺激功能所必需的。对IL-10受体配体结合链（IL10R1）的胞内结构域（ICD）的结构-功能分析显示，尽管所有IL-10的作用都需要包含转录因子Stat3受体对接位点的ICD区域的存在，但IL-10的抗炎作用选择性地需要额外存在il - 10r1羧基端。基于这一观察，我们询问是否可以鉴定IL-10诱导基因，其调控需要IL-10R1 ICD的两个功能重要区域。利用代表性差异分析，我们鉴定并克隆了一个新的il -10诱导基因（标记为TIGER），其诱导满足这些标准，并产生了缺乏TIGER基因位点的小鼠。在Specific Aim 1中，我们建议研究TIGER-/-小鼠来评估该基因的生理功能。IL-10依赖性的TIGER诱导需要新的蛋白合成，目前尚不清楚IL-10的抗炎作用是否需要TIGER的表达。因此，在Specific Aim 2中，我们将进行基于微芯片的基因分析实验，以鉴定一组il -10调节基因，这些基因的诱导既独立于蛋白质合成（即即时早期基因），又需要IL-10R1 ICD的两个功能重要区域。这些基因将在特异性Aim 3中用于定义IL-10受体用于选择性抑制炎症和/或先天免疫反应的信号转导途径。这项工作将确定IL-10抗炎作用的分子基础，从而为我们提供通过干扰该信号通路非特异性增强对感染因子抗性的新策略。

DESCRIPTION (provided by applicant): IL-10 is a cytokine that has contrasting effects on immune system function. It promotes humoral immunity by enhancing proliferation, survival, and differentiation of B cells, but inhibits innate immunity by ablating production of pro-inflammatory cytokines from myeloid cells and from lymphocytes. IL-10manifests its effects by binding to a specific receptor expressed on many different immune cells. Our previous work helped define the IL-10 receptor and demonstrated that the JAK-STAT signaling path way is required for all IL-10 receptor stimulated functions. A structure-function analysis on the intracellular domain (ICD) of the IL-10 receptor ligand binding chain (IL10R1) revealed that, whereas all IL-10's actions required the presence of an ICD region containing the receptor docking site for the transcription factor Stat3, IL-10's anti-inflammatory effects selectively required the additional presence of the IL-10R1carboxyl terminus. Based on this observation we asked whether we could identify IL-10 induced genes whose regulation required both functionally important regions of the IL-10R1 ICD. Using representation difference analysis, we identified and cloned a novel IL-10-induced gene (denoted TIGER) whose induction fulfills these criteria and have generated a mouse that lacks the TIGER gene locus. In Specific Aim 1, we propose to study the TIGER-/- mouse to assess the physiologic function of this gene. IL-10 dependent induction of TIGER requires new protein synthesis and we currently do not know whether TIGER expression is required for IL-10's anti-inflammatory effects. Thus in Specific Aim 2 we will conduct microchip-based gene profiling experiments to identify a panel of IL-10-regulated genes whose induction is both independent of protein synthesis (i.e. are immediate-early genes) and requires both functionally important regions of the IL-10R1 ICD. These genes will then be used in Specific Aim 3 to define the signal transduction pathway that the IL-10 receptor uses to selectively inhibit inflammatory and/or innate immune responses. This work should identify the molecular basis for IL-10's anti-inflammatory effects and should thus provide us with novel strategies to nonspecifically enhance resistance to infectious agents by interfering with this signaling pathway.