Innate Immune Response Genes and P. Gingivalis

描述：牙周病是与病原菌的殖民地龈下地区。先天免疫系统细胞介导的炎症反应是牙周病的关键决定因素。最常见的细菌之一是牙龈卟啉单胞菌（Porphyromonas gingivalis，Pg）。牙周炎被认为是由先天免疫系统的细胞，即单核细胞/巨噬细胞和粒细胞的反应引起的宿主组织损伤引起的。近年来，Toll样受体（TLR）已迅速成为先天免疫系统识别微生物病原体的主要途径。TLR激活需要邻近TLR的许多细胞内衔接蛋白，包括MyD 88、TRAF 6、MD-2和TRAM。最近，我们已经确定了一个蛋白质家族，进一步调节TLR信号，称为CATERPILLER蛋白。其中两种，Monarch-1和CIAS/cryopyrin，是NF-κ B，AP-1和细胞因子产生的新型抑制剂。然而，这两种蛋白质的功能依赖于修饰蛋白ASC（具有CARD的凋亡斑点蛋白），其颠覆了它们的负功能，并导致促炎表型。本申请的目的是了解TLR、其衔接子、CATERPILLER蛋白和ASC在Pg感染期间的作用。比较宿主对Pg和E.以评估Pg是否引起独特的宿主反应。因此，目的是：1）确定哪些TLR分子及其下游介体对于宿主对Pg vs. E的应答信号是重要的。杆菌这将通过使用RNA干扰技术来靶向人TLR和TLR接头基因来实现;我们将确定这些基因的去除是否会导致宿主对Pg的反应改变，如通过细胞因子反应和基因表达谱所测量的。2)缺乏Monarch-1的单核细胞/巨噬细胞细胞系将与1）中类似地进行测试。由于Monarch-1似乎是NF-κ B和AP-1通路的抑制分子，并且可以调节细胞因子的产生，因此我们认为Monarch-1的缺失可能有利于更有力的促炎反应。3)将类似地测试缺乏或过表达CIAS/cryopyrin（另一种炎症反应调节剂）的细胞系。4)还将检测ASC减少的细胞系。由于ASC可以克服Monarch-1和CIAS的负调节作用，ASC可能增强对Pg的免疫应答以抑制感染。

DESCRIPTION: Periodontal diseases are associated with pathogenic bacteria which colonize the subgingival area. Inflammatory responses mediated by cells of the innate immune system are critical determinants of periodontal diseases. One of the most prominent bacteria is Porphyromonas gingivalis (Pg). Periodontitis is thought to result from host tissue injury caused by the response of cells of the innate immune system, namely monocytes/macrophages and granulocytes. In recent years, the Toll-like receptors (TLR) have rapidly emerged as a dominant route by which the innate immune system recognizes microbial pathogens. TLR activation requires a host of intracellular adaptor proteins proximal to the TLRs, including MyD88, TRAF6, MD-2 and TRAM. More recently, we have identified a family of proteins that further modulate TLR signaling, called the CATERPILLER proteins. Two of these, Monarch-1 and CIAS/cryopyrin, are novel inhibitors of NF-kappaB, AP-1 and cytokine production. Nevertheless, the function of these two proteins is dependent on a modifier protein ASC (Apoptotic Speck protein with a CARD), which subverts their negative function, and causes a pro-inflammatory phenotype. The purpose of this application is to understand the roles of TLRs, their adaptors, CATERPILLER proteins and ASC during a Pg infection. Comparisons of host response to Pg vs. E. coli will be made to assess if Pg elicits unique host responses. Accordingly, the Aims are: 1) to determine which TLR molecules and their downstream mediators are important to signal host responses to Pg vs. E. coli. This will be achieved by using RNA interference technology to target human TLRs and TLR adaptor genes; we will determine if the removal of these genes causes alterations in host response to Pg as measured by cytokine responses, and by gene expression profile. 2) Monocytic/macrophage cell lines that lack Monarch-1 will be similarly tested as in 1). Since Monarch-1 appears to be an inhibitory molecule of the NF-kB and AP-1 pathway, and can modulate cytokine production, we posit that the absence of Monarch-1 may favor a more vigorous pro-inflammatory response. 3) Cell lines that lack or overexpress CIAS/cryopyrin, another modulator of inflammatory response will be similarly tested. 4) Cell lines with reduced ASC will also be tested. Since ASC can overcome the negative regulatory function of Monarch-1 and CIAS, ASC may enhance immune response to Pg to contain the infection.