Probing macrophage cell nucleotide sensing and calcium signaling through computation

通过计算探测巨噬细胞核苷酸传感和钙信号传导

• 批准号: 10552460
• 负责人: Peter Michael Kekenes-Huskey
• 金额: $ 42.01万
• 依托单位: LOYOLA UNIVERSITY CHICAGO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10552460
• 关键词: Acceleration; Adenosine Triphosphate; Attenuated; Automobile Driving; Award; Calcium Signaling; Calmodulin; Cells; Chronic; Computer Models; Coupling; Disease; Elements; Eukaryotic Cell; Functional disorder; Goals; Grant; Immune; Immune response; Immune system; Inflammation; Inflammatory; Inflammatory Response; Investigation; Leukocytes; Macrophage; Malignant Neoplasms; Mediating; Modeling; Myocardial dysfunction; Nucleotides; Outcome; P2X-receptor; Pathway interactions; Phagocytosis; Physiological; Physiology; Positioning Attribute; Post-Translational Protein Processing; Process; Proteins; Reactive Oxygen Species; Research; Rest; Role; Sepsis; Signal Induction; Signal Pathway; Signal Transduction; System; Tissues; Up-Regulation; cell behavior; computerized tools; cytokine; ecto-nucleotidase; healing; human disease; immune function; insight; migration; multi-scale modeling; oxidation; pathogen; receptor; sensor; simulation; stem; tool

While inflammation is a natural immune system response that begins the healing process, chronic inflam- mation is tied to many human diseases including cancer, cardiac dysfunction, and sepsis. A key element of inflammatory responses are macrophages, a white blood cell that eliminates pathogens or dying tissues. An endogenous 'danger signal', adenosine triphosphate (ATP), stimulates Ca-dependent inflammatory pathways in macrophages. While previous research has made great strides in understanding inflammation, my lab seeks to uncover roles of ATP in driving macrophage inflammatory responses through multi-scale computational models we develop. With new models of inflammatory responses in macrophages, our lab can predict protein and cell behavior in integrated, physiological systems to better understand the immune system. The current paradigm for ATP-triggered inflammation in macrophages is that upregulation of nucleotide- sensing P2X channels sensitizes inflammatory responses, including cytokine and reactive oxygen species (ROS) release. However, this paradigm does not account for several observations. One, while P2X expression is increased in inflammatory macrophages, these receptors also support phagocytosis and migration in resting macrophages. How these processes are selectively controlled by P2X subtypes like P2X4 and P2X7 is unresolved. Two, inflammatory macrophages harbor post-translational modifications (PTMs) of many proteins that sense Ca, yet little is known about how PTMs impact immune pathways they control. Three, release and degradation of ATP by pannexins and ectonucleotidases control ATP that activates P2X, yet few studies have evaluated their coupling. Our lab is uniquely positioned to extend this paradigm by probing mechanisms underlying these observations and the largely unstudied coupling of P2X-, ATP-, and Ca-driven inflammation. Our lab and assembled collab- orators will investigate the overall hypothesis via computational modeling and experimental approaches: P2X channels in macrophages help nucleate chronic inflammation via ATP-induced ATP release (autocrinic) mechanisms that selectively prime Ca-dependent, pro-inflammatory signaling pathways. This hypothesis stems from questions that emerged from our investigations during the initial ESI MIRA award: 1. Does increased P2X4 and P2X7 expression and the resulting Ca signals they induce in macrophages prolong pro-inflammatory release of cytokines and ROS? 2. Do PTMs like ROS oxidation in the Ca-sensor calmodulin (CaM) attenuate its activation of pro-inflammatory signaling pathways? 3. Do (autocrinic) ATP-induced, ATP release in macrophages prolong pro-inflammatory increases in intracellular Ca? Our long-term goal to understand macrophage physiology through computation will be accelerated by the proposed investigations. Key expected outcomes from this grant period include new mechanisms and simulation tools for autocrinic, ATP-driven inflammatory responses mediated by P2X receptors. Since all Eukaryotic cells use Ca, insights from modeling macrophages will have broad impacts beyond immune function.

虽然炎症是一种开始愈合过程的自然免疫系统反应，但慢性炎症 炎症与许多人类疾病有关，包括癌症、心脏功能障碍和败血症。 炎症反应是巨噬细胞，一种消除病原体或垂死组织的白细胞。 内源性“危险信号”三磷酸腺苷 (ATP) 可刺激 Ca 依赖性炎症通路 虽然之前的研究在了解炎症方面取得了很大进展，但我的实验室致力于 通过多尺度计算模型揭示 ATP 在驱动巨噬细胞炎症反应中的作用 我们开发了巨噬细胞炎症反应的新模型，我们的实验室可以预测蛋白质和细胞。 综合生理系统的行为，以更好地了解免疫系统。 当前巨噬细胞中 ATP 触发炎症的范例是核苷酸- 传感 P2X 通道使炎症反应敏感，包括细胞因子和活性氧 (ROS) 然而，这个范式并没有解释几个观察结果，而 P2X 表达是。 炎症巨噬细胞增加，这些受体还支持静息时的吞噬作用和迁移 巨噬细胞如何通过 P2X 亚型（如 P2X4 和 P2X7）选择性控制这些过程尚未解决。 第二，炎症巨噬细胞含有许多可感知 Ca 的蛋白质的翻译后修饰 (PTM)， 然而，人们对 PTM 如何影响其控制的免疫途径知之甚少。 第三，ATP 的释放和降解。 pannexins 和核酸外切酶控制 ATP 激活 P2X，但很少有研究评估它们的耦合。 我们的实验室具有独特的优势，可以通过探索这些观察结果背后的机制来扩展这一范式 以及 P2X、ATP 和 Ca 驱动的炎症的耦合很大程度上未经研究，我们的实验室和组装的合作伙伴。 演讲者将通过计算模型和实验方法研究总体假设：P2X 巨噬细胞中的通道通过 ATP 诱导的 ATP 释放（自分泌）帮助形成慢性炎症 选择性启动 Ca 依赖性促炎症信号通路的机制。 源于我们在最初的 ESI MIRA 颁奖期间调查中出现的问题： 1. 是否增加了 P2X4 和 P2X7 表达以及它们在巨噬细胞中诱导的 Ca 信号延长促炎作用 2. Ca 传感器钙调蛋白 (CaM) 中的 ROS 氧化等 PTM 会减弱其作用吗？ 3. 巨噬细胞中（自分泌）ATP 诱导的 ATP 释放吗？ 延长细胞内 Ca2+ 的促炎性增加？ 我们通过计算了解巨噬细胞生理学的长期目标将加速实现 拟议调查的主要预期成果包括新机制和 由 P2X 受体介导的自分泌、ATP 驱动的炎症反应的模拟工具。 真核细胞使用 Ca，巨噬细胞建模的见解将产生免疫功能之外的广泛影响。