Perturbations of host cell signaling by a complex hepatotropic pathogen

复杂的嗜肝病原体对宿主细胞信号传导的干扰

• 批准号: 10677933
• 负责人: Alexis Kaushansky
• 金额: $ 63万
• 依托单位: SEATTLE CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-04-01 至 2028-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10677933
• 关键词: Animals; Antigen-Presenting Cells; Antigens; Apoptosis; Apoptotic; Biological; Blood; CD8-Positive T-Lymphocytes; CRISPR screen; Cell Death; Cell Survival; Cells; Cessation of life; Characteristics; Collection; Complex; Culicidae; Data; Development; Disease; Dissection; Environment; Equilibrium; Erythrocytes; Genetic; Genetic Transcription; Growth and Development function; Hepatocyte; Host Defense; Human; Immune; Immune response; Immunity; Immunologic Stimulation; Immunologics; In Situ; Individual; Infection; Inflammatory; Integration Host Factors; Internet; Intervention; Invaded; Investigation; Knock-out; Lipid Peroxidation; Lipid Peroxides; Liver; LoxP-flanked allele; Macrophage; Malaria; Mediating; Mediator; Medical; Mitochondria; Molecular; Mus; Nature; Outcome; Parasites; Parasitic infection; Pathway interactions; Persons; Plasmodium; Process; Proteomics; Research; Resources; Robot; Role; Signal Transduction; Site; Sterility; Stimulus; Stream; System; T cell response; T-Cell Development; T-Lymphocyte; Technology; Testing; Tissues; Vaccination; Vaccines; cell killing; cell type; comparative; cytokine; design,build,test; experimental study; genome-wide; in vivo; insight; liver infection; malaria infection; migration; pathogen; prevent; recruit; response; small molecule; tool; transcriptomics; transmission process; whole genome

ABSTRACT During Plasmodium parasite liver stage infection, parasites protect their host hepatocyte by preventing its death and exploiting host resources for growth and development. This process is imperfect, as some parasites succumb to host defenses and are eliminated by host cell death; this, in turn, elicits an immune response. This proposal is focused on the investigation of molecular mechanisms in the hepatocyte that curtail, or promote, malaria parasite infection and the immunological consequences of those outcomes. After transmission by a mosquito, Plasmodium parasites are carried by the blood stream to the liver and invade a single hepatocyte to form a liver stage. Throughout the liver stage we have shown that both apoptosis and lipid peroxide mediated death pathways curtail infection. Whether the infected cell survives or succumbs to host cell death has consequences that expand beyond the individual infection; parasites that are eliminated via hepatocyte cell death can provide potent stimuli for the subsequent immune response and the nature of the immune stimulation is partially dependent on the type of regulated cell death engaged. Indeed, we show that immune cell subsets, in particular immune cells with markers consistent with tolerogenic macrophages, sequester around the parasite during liver infection. Additionally, eliminating apoptosis, a sterile form of cell death, reduces immunity in response to whole parasite vaccination. This proposal aims to test the hypothesis that multiple forms of cell death can control Plasmodium infection and that altering the balance between sterile and inflammatory forms of cell death impacts subsequent immunity to parasite infection. To test this hypothesis, we will make extensive use of animal and technological tools. First, we will use mice with cell death pathways eliminated exclusively in hepatocytes to examine the specific role of each type of cell death in regulating wild type parasites and parasites with multiple biological deficiencies. We will use genome wide CRISPR/Cas9 screens to identify specific genetic regulators of cell death in infected cells and we will make use of a mosquito dissection robot that we have recently designed, built, and tested to perform larger, more unbiased analyses than previously possible. We will also take advantage of state-of-the-art spatial profiling approaches that facilitate the collection of proteomic and transcriptomic information in situ for Plasmodium-infected livers to examine infected cells, and the surrounding immune environment. In addition to identifying mediators of initial infection, will use these tools to ask how altered hepatocyte death primes CD8 T cell responses and informs immunity to subsequent infection. Accomplishing our aims enables altering key host factors with small- molecules that could prevent a wild-type parasite from progressing to symptomatic erythrocytic infection or eliminate infection in a way that elicits a potent immune response against subsequent challenge.

抽象的 在疟原虫寄生虫阶段感染期间，寄生虫通过防止其宿主肝细胞保护其宿主 死亡和利用宿主资源以进行增长和发展。这个过程是不完美的，因为某些寄生虫 屈服于宿主防御，并被宿主细胞死亡消除；反过来，这引起了免疫反应。这 提案的重点是研究肝细胞中分子机制的研究，以减少或促进，促进或促进 疟疾寄生虫感染和这些结果的免疫学后果。通过 蚊子，疟原虫寄生虫被血液流到肝脏中，并侵入一个肝细胞 形成肝阶段。在整个肝脏阶段，我们已经表明凋亡和脂质过氧化 死亡道路减少感染。感染的细胞是否幸存还是屈服于宿主细胞死亡 超越个体感染的后果；通过肝细胞消除的寄生虫 死亡可以为随后的免疫反应和免疫的性质提供有效的刺激 刺激部分取决于调节细胞死亡的类型。确实，我们证明了免疫力 细胞子集，特别是具有与耐受性巨噬细胞一致的标志物的免疫细胞， 肝脏感染期间寄生虫周围。另外，消除了细胞凋亡，一种无菌形式的细胞死亡形式， 响应整个寄生虫疫苗接种而降低免疫力。该建议旨在检验以下假设 多种形式的细胞死亡可以控制疟原虫感染，并改变无菌和无菌之间的平衡 细胞死亡的炎症形式随后对寄生虫感染的免疫力。为了检验这一假设，我们 将广泛使用动物和技术工具。首先，我们将使用小鼠与细胞死亡途径 仅在肝细胞中消除，以检查每种细胞死亡在调节野生中的特定作用 类型具有多种生物缺陷的寄生虫和寄生虫。我们将使用基因组宽CRISPR/CAS9 筛选以鉴定受感染细胞中细胞死亡的特定遗传调节剂，我们将利用蚊子 我们最近设计，构建和测试以执行更大，公正的分析的解剖机器人 比以前可能。我们还将利用最先进的空间分析方法 促进在原位收集元素的蛋白质组学和转录组信息，以归因于疟原虫感染的肝脏 检查受感染的细胞以及周围的免疫环境。除了确定初始的调解人 感染，将使用这些工具来询问肝细胞死亡素质变化如何CD8 T细胞反应并告知 对随后感染的免疫力。实现我们的目标可以通过小型宿主因素改变关键的宿主因素 可以防止野生型寄生虫发展到症状性红细胞感染或 消除感染，以引起对随后挑战的有效免疫反应。