The role of TLR3 signaling in Chlamydia caused urogenital pathology

描述(申请人提供)：衣原体感染引起的生殖道病理是女性生殖道内免疫反应的结果。先天和获得性免疫反应都是作为宿主防御感染的一部分而诱导的，特定的细胞因子和趋化因子在调节这些防御机制中发挥作用。由于在生殖道感染过程中，上皮细胞是衣原体感染的主要细胞类型，我们研究的总体目标是了解感染的上皮细胞对宿主防御的贡献。我们发现，在输卵管上皮细胞(OE)中，干扰素-�的合成主要以TLR3依赖的方式发生。初步数据显示，来自TLR3缺陷小鼠的OE细胞在合成参与先天炎症反应的多种炎性细胞因子和趋化因子方面存在缺陷。初步实验比较了衣原体感染在野生型和TLR3缺陷小鼠之间的致病机制，结果表明TLR3对衣原体诱导的生殖道病理具有保护性免疫反应。这一新的观察结果显示，在TLR3基因缺陷的小鼠中，某些炎性细胞因子和趋化因子的合成减少，提出了TLR3调节这些炎性介质的合成的假设，这有助于在衣原体感染期间对宿主免疫反应产生积极影响。我们的研究计划将包括进一步检验TLR3在体内对衣原体疾病的贡献，进一步检验我们的假设，即缺乏TLR3的小鼠在生殖道病理上将有显着差异。我们建议对生殖道进行初步鉴定 通过大体和显微组织学检查、淋巴细胞浸润、炎性介质合成等方法，对野生型和TLR3缺陷型小鼠进行病理学观察，进而确定TLR3信号在感染过程中对小鼠生殖道细菌复制的影响。接下来，我们建议使用相同的方法来确定干扰素-�在鼠隐孢子虫感染的发病机制中的具体作用，并将确定不需要干扰素-�合成的、有助于生殖病理的TLR3依赖机制。最后，我们建议使用TLR3特异性细胞试验在体外鉴定衣原体感染的成分，作为TLR3刺激的PAMP。

DESCRIPTION (provided by applicant): Reproductive tract pathology caused by Chlamydia infections are the result of the immune responses within the female reproductive tract. Both innate and adaptive immune responses are induced as part of the host defense against infection, and specific cytokines and chemokines play a role in regulating these defense mechanisms. Because epithelial cells are the major cell type productively infected with Chlamydia during genital tract infections, the overall goal of our research is to understand the contribution of the infected-epithelial cells to the host defense. We showed that IFN-� synthesis in oviduct epithelial (OE) cells occurred in a mostly TLR3-dependent manner. Preliminary data show that OE cells derived from TLR3- deficient mice were defective in the synthesis of a multitude of inflammatory cytokines and chemokines involved in the innate inflammatory response. Pilot experiments comparing the pathogenesis of Chlamydia infection between wild-type and TLR3-deficient mice show that TLR3 elicits a protective immune response against Chlamydia-induced genital-tract pathology. The novel observation showing diminished synthesis of certain inflammatory cytokines and chemokines in TLR3-deficient mice, presents the hypothesis that TLR3 regulates the synthesis of these inflammatory mediators which contributes to its positive impact on the host immune response during Chlamydia infection. Our research plan will involve further examining the in vivo contributions of TLR3 to Chlamydia disease by further testing our hypothesis that mice deficient in TLR3-deficient mice will have significant differences in reproductive tract pathology. We propose to initially qualify the reproductive tract pathology in wild-type versus TLR3-deficient via gross and microscopic histological examination, lymphocyte infiltration, inflammatory mediator synthesis, and then determining the effect that TLR3 signaling has bacterial replication in the reproductive tracts of the mice during infection. We next propose to ascertain the role of IFN-� specifically in the pathogenesis of C. muridarum infection using the identical methodologies, and we will identify the TLR3-dependent mechanisms that contribute to reproductive pathology that do not require IFN-� synthesis. Finally, we propose to identify the component of the Chlamydia infection that serves as the PAMP for TLR3 stimulation in vitro using a TLR3-specific cellular assay.