Role of JNK2 and TLR6 during Y. enterocolitica induced mucosal immune responses

描述（由申请人提供）： IL-10是肠粘膜中针对口服摄入的抗原和针对肠道微生物菌群的稳态应答的关键细胞因子。IL-10可以通过诱导引发致耐受性应答的DC（称为致耐受性DC）来发挥其作用。有人提出，致耐受性DC引发1型调节（Tr 1）细胞，一种产生大量IL-10并抑制炎症的T细胞亚群。然而，致耐受性DC和（Tr 1）细胞在肠道中产生的分子机制仍然知之甚少。这项计划的目的是确定如何IL-10产生细胞在肠道免疫组织中产生使用Y。小肠结肠炎感染作为模型系统。是什么让Y。小肠结肠炎球菌是检查IL-10介导的粘膜应答的诱导的理想选择，因为其对小肠的免疫部位，特别是派伊尔集合淋巴结和MLN，免疫细胞诱导和T细胞引发的两个部位的向性。更重要的是，Y。小肠结肠炎携带低钙应答V抗原（LcrV），其是在所有三种致病性耶尔森氏菌属物种中发现的必需毒力因子，并且已显示其从抗原呈递细胞（APC）诱导IL-10。使用系统Y.我们发现LcrV诱导致耐受性DC并以TLR 6依赖性方式引发Tr 1细胞应答。此外，我们的初步研究表明，TLR 6是唯一参与的耐受性DC和Tr 1通过激活MAPK JNK的产生。我们推测TLR 6和JNK在肠粘膜耐受性DC和Tr 1细胞的产生中起关键作用。此外，我们预期TLR 6和JNK在Y.小肠结肠炎发病机制我们的具体目标是研究[原文如此]，1）使用来自TLR缺陷型和JNK缺陷型小鼠的粘膜DC评估致耐受性DC和Tr 1细胞的诱导，所述小鼠在体外由LcrV刺激或感染Y。小肠结肠炎2)探讨TLR 6和JNK在口腔Y染色体病发病中的作用。小肠结肠炎在这个目标中，我们将利用基因敲除小鼠以及通过使用IL-10-T细胞报告小鼠繁殖TLR-缺陷和JNK-缺陷的小鼠，希望确定IL-10诱导的粘膜位点，并评估在感染过程中诱导的粘膜CD 4 T细胞是否可以转移耐受性并将耐受性传播到第二抗原。3)使用抗LcrV和LcrV缺失突变体的单克隆抗体鉴定LcrV内负责诱导IL-10和激活JNK的特定残基。 公共卫生相关性：了解Y。小肠结肠炎诱导肠道Tr 1和耐受性DC，可能会给我们关键的洞察了解肠组织如何产生调节反应的稳态。

DESCRIPTION (provided by applicant): IL-10 is a critical cytokine for homeostatic responses in the intestinal mucosa, both against orally ingested antigens and against commensal microflora. IL-10 can exert its effects through the induction of DC that prime tolerogenic responses, referred to as tolerogenic DC. It is proposed that tolerogenic DC prime type-1 regulatory (Tr1) cells, a subset of T cell that produce high amounts of IL-10 and suppress inflammation. However, the molecular mechanism of tolerogenic DC and (Tr1) cell generation in the intestine remain poorly understood. The goal of this proposal is to determine how IL-10-producing cells are generated in the intestinal immune tissue using Y. enterocolitica infection as a model system. What makes Y. enterocolitica an ideal choice for examining induction of IL-10-mediated mucosal responses is because of its tropism for immune sites of the small intestine, specifically the Peyer's patches and the MLN, both sites of immune cell induction and T cell priming. More importantly, Y. enterocolitica harbors the Low Calcium Response V Antigen (LcrV) an essential virulence factor found in all three pathogenic Yersinia species and which has been shown to induce IL-10 from antigen presenting cells (APC). Using systemic Y. pestis infection we found that LcrV induced tolerogenic DC and primed a Tr1 cell response in a TLR6 dependent manner. Furthermore, our initial studies suggest that TLR6 is uniquely involved in the generation of tolerogenic DC and Tr1 through activation of the MAPK JNK. We hypothesize that TLR6 and JNK will play a key role in the generation of mucosal intestinal tolerogenic DC and Tr1 cells. Furthermore, we anticipate that TLR6 and JNK play an important role in Y. enterocolitica pathogenesis. Our specific aims will investigate [sic], 1) Evaluate the induction of tolerogenic DC and Tr1 cells using mucosal DC from TLR-deficient and JNK-deficient mice stimulated in vitro by LcrV or infected with Y. enterocolitica. 2) Evaluate the role TLR6 and JNK play during pathogenesis of oral Y. enterocolitica infection. In this aim we will utilize knockout mice as well as by using IL-10-T cell reporter mice bred to TLR-deficient and JNK-deficient mice in hopes to identify the mucosal sites of IL-10 induction and evaluate whether mucosal CD4 T cells induced during infection can transfer tolerance and spread tolerance to a second antigen. 3) Use monoclonal antibodies against LcrV and LcrV deletion mutants to identify specific residues within LcrV responsible for inducing IL-10 and activating JNK. PUBLIC HEALTH RELEVANCE: Understanding the molecular mechanism that Y. enterocolitica induces intestinal Tr1 and tolerogenic DC, may give us critical insight into understanding how intestinal tissue generates regulatory responses homeostatically.