Genetic Determinants of Aspergillus host-pathogen interactions

曲霉菌宿主-病原体相互作用的遗传决定因素

• 批准号: 10724816
• 负责人: Jarrod R. Fortwendel
• 金额: $ 23.1万
• 依托单位: UNIVERSITY OF TENNESSEE HEALTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-23 至 2025-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10724816
• 关键词: Address; Allergic Bronchopulmonary Aspergillosis; Anabolism; Aspergillosis; Aspergillus; Aspergillus fumigatus; Asthma; Automobile Driving; Caspase; Cell Line; ChIP-seq; Chronic; Clinical; Coculture Techniques; Complex; Cystic Fibrosis; Development; Fungal Components; Future; Gene Deletion; Gene Expression Profile; Gene Expression Profiling; Genetic Determinism; Genetic Epistasis; Genetic Transcription; Goals; Human; Immune response; Immunity; Immunocompetent; Immunocompromised Host; In Vitro; Individual; Infection; Inflammasome; Inflammation; Inflammatory Response; Interleukin-1 beta; Libraries; Macrophage; Masks; Measures; Mediating; Molecular; Morbidity - disease rate; Organism; Pathogen detection; Pathogenicity; Pathway interactions; Patients; Pattern; Peripheral Blood Mononuclear Cell; Phagocytosis; Process; Protein Kinase; Proteins; Regulation; Research; Research Design; Role; Screening Result; Severities; Signal Transduction; Stimulus; Stress Response Signaling; Syndrome; Tissue-Specific Gene Expression; Virulence; Work; biological adaptation to stress; chronic infection; diagnostic criteria; fungus; gene complementation; immunological status; immunopathology; improved outcome; in vivo; molecular assembly/self assembly; monocyte; mortality; mouse model; mutant; new therapeutic target; novel; novel therapeutic intervention; pathogen; pathogenic fungus; protein-histidine kinase; respiratory; response; sensor histidine kinase; therapeutic target; tool; transcription factor; transcriptome sequencing

The long-term goal of our work is to reduce the morbidity and mortality associated with Aspergillus infections by improving outcomes of host-pathogen interactions. Aspergillus fumigatus is the major airborne fungal pathogen and is responsible for a range of clinical syndromes, the severity of which is dependent on host immune status. Invasive pulmonary aspergillosis and disseminated infections can occur in severely immunocompromised hosts and are often associated with mortality rates of up to 90%. In immune competent hosts, A. fumigatus colonization can lead to chronic pulmonary aspergillosis (CPA), a clinical manifestation with recently defined diagnostic criteria that impacts upwards of 1.6 million individuals per year. Many individuals with CPA have underlying respiratory conditions, such as asthma or cystic fibrosis, that are further exacerbated by the presence of the fungus. Although multiple Pathogen-Associated Molecular Patterns (PAMPs) driving host recognition and response are known, uncovering novel fungal molecular pathways that could serve as therapeutic targets to enhance or mask PAMP display and/or biosynthesis could prove useful therapeutic targets to modulate host response for improved outcomes. To address this, we utilized activation of the inflammasome, a multiprotein intracellular complex that detects pathogenic organisms to initiate inflammatory responses, as a tool to uncover Aspergillus mutants with altered abilities to activate host response. We have completed a preliminary screen to measure IL-1β secretion from a macrophage differentiated human monocyte cell line employing an A. fumigatus protein kinase disruption library recently generated in our lab. Of 118 protein kinase disruption mutants screened, we identified seven A. fumigatus protein kinases that either significantly increased (n=2) or decreased (n=5) inflammasome-dependent IL-1β secretion upon disruption. Strikingly, both of the protein kinase disruption mutants that induced increased IL-1β release encode phospho-relay sensor histidine kinases (phkA and fhk3), a sub-class of protein kinases that directly sense environmental and intracellular changes and subsequently activate stress response signaling. The molecular pathways controlled by PhkA and Fhk3 are unknown, as both HKs are largely uncharacterized. Although a major consequence of HK signaling is activation of stress responses pathways that upregulate transcription factor activity to respond to environmental stimuli, the downstream transcriptional effectors for all A. fumigatus HKs remain undescribed. Our work will delineate A. fumigatus histidine kinase (HK)-dependent mechanisms of host response (Aim 1) and identify A. fumigatus transcriptional regulators of inflammasome activation (Aim 2). Through completion of the proposed Aims, we will delineate fungal molecular pathways mediating Aspergillus-induced host response. This work is essential for future development of novel therapeutic approaches targeted towards activating protection against invasive infections or mitigating harmful host-response during chronic infections.

我们工作的长期目标是通过以下方式降低曲霉感染相关的发病率和死亡率： 改善宿主与病原体相互作用的结果。烟曲霉是主要的空气传播真菌病原体 并导致一系列临床综合征，其严重程度取决于宿主免疫状态。 侵袭性肺曲霉病和播散性感染可能发生在严重免疫功能低下的宿主中 并且通常与高达 90% 的死亡率相关。在免疫能力强的宿主中，烟曲霉定植 可导致慢性肺曲霉病 (CPA)，这是一种最近定义的诊断临床表现 标准每年影响超过 160 万人。许多拥有注册会计师 (CPA) 的人都有潜在的 呼吸系统疾病，例如哮喘或囊性纤维化，这些疾病的存在会进一步加剧 菌。尽管多种病原体相关分子模式（PAMP）驱动宿主识别和 反应是已知的，揭示了新的真菌分子途径，可以作为治疗靶点 增强或掩盖 PAMP 显示和/或生物合成可能证明调节宿主的有用治疗靶点 改善结果的响应。为了解决这个问题，我们利用了炎症小体的激活，炎症小体是一种多蛋白 检测病原微生物以引发炎症反应的细胞内复合物，作为发现的工具 曲霉突变体具有改变激活宿主反应的能力。我们已经完成了初步筛选 使用烟曲霉测量巨噬细胞分化的人单核细胞系的 IL-1β 分泌 我们实验室最近生成了蛋白激酶破坏库。在筛选的 118 个蛋白激酶破坏突变体中， 我们鉴定了七种烟曲霉蛋白激酶，它们要么显着增加（n = 2），要么显着减少（n = 5） 破坏后炎症小体依赖性 IL-1β 分泌。引人注目的是，这两种蛋白激酶均被破坏 诱导 IL-1β 释放增加的突变体编码磷酸中继传感器组氨酸激酶（phkA 和 fhk3）， 蛋白激酶的一个子类，可直接感知环境和细胞内的变化，并随后 激活应激反应信号。 PhkA 和 Fhk3 控制的分子途径尚不清楚，因为两者 HK 基本上没有特征。尽管 HK 信号传导的一个主要后果是应激反应的激活 上调转录因子活性以响应环境刺激的途径，下游 所有烟曲霉 HK 的转录效应子仍未被描述。我们的工作将描述烟曲霉 组氨酸激酶 (HK) 依赖性宿主反应机制（目标 1）并鉴定烟曲霉转录 炎症小体激活的调节因子（目标 2）。通过完成拟议的目标，我们将描绘 介导曲霉诱导的宿主反应的真菌分子途径。这项工作对未来至关重要 开发新的治疗方法，旨在激活针对侵袭性感染的保护 或减轻慢性感染期间有害的宿主反应。