Lung epithelium collaborates with alveolar macrophages in host defense

肺上皮与肺泡巨噬细胞合作进行宿主防御

• 批准号: 8367586
• 负责人: Min Wu
• 金额: $ 41.4万
• 依托单位: UNIVERSITY OF NORTH DAKOTA
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-16 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8367586
• 关键词: Accounting; Acids; Acquired Immunodeficiency Syndrome; Alveolar; Alveolar Macrophages; Alveolus; Anti-Bacterial Agents; Antibiotic Resistance; Area; Bacteria; Biochemical; Burn injury; CCL2 gene; Cell model; Ceramides; Chemicals; Chronic; Clinical; Cystic Fibrosis; Cytokine Activation; Data; Development; Education; Epithelial; Epithelial Cells; Epithelium; Funding; Goals; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Grant; HIV-1; Hospital Charges; Host Defense; Human; Hydrolysis; Immune; Immunity; Immunocompromised Host; In Situ Hybridization; Individual; Infection; Inflammatory Response; Laboratories; Lower respiratory tract structure; Lung; Macrophage Activation; Malignant Neoplasms; Manuscripts; Mediating; Membrane Lipids; Membrane Microdomains; Microscopy; Modeling; Monocyte Chemoattractant Proteins; Mus; Natural Immunity; North Dakota; Nosocomial Infections; Play; Population; Production; Pseudomonas aeruginosa; Recruitment Activity; Research; Respiratory Tract Infections; Retroviral Vector; Role; Scheme; Site; Small Interfering RNA; Source; Sphingolipids; Stem cells; Students; Techniques; Testing; Training; Translational Research; Tuberculosis; Type II Epithelial Receptor Cell; Universities; Work; acid sphingomyelinase; alveolar type II cell; base; cell type; chemokine; combat; cytokine; defense response; design; experience; graduate student; high school; immune function; inhibitor/antagonist; innovation; insight; interest; macrophage; microbicide; novel; novel therapeutics; pathogen; programs; respiratory; response; therapeutic development; undergraduate student

DESCRIPTION (provided by applicant): P. aeruginosa (PA) frequently infects immunocompromised individuals with HIV-1, cancer, and cystic fibrosis (CF). Since PA is increasingly resistant to antibiotics, its infection often leads to either severe states or chronic situations with a persistent inflammatory response. Better understanding of host-pathogen interaction may suggest a more effective approach to combating this pathogen. MCP-1 is a major chemokine secreted by alveolar epithelial cells type II (AECII). Recent research has illustrated an immune role of AECII in PA infection, but the underlying mechanism remains unidentified. Our long-term goal is to understand the mechanism of host immunity and develop new strategies for controlling respiratory infections. The objective of this application is to elucidate the immune function of AECII, in particular through their secretion of cytokines and activation of AM. Our central hypothesis is that AECII can secrete cytokines (MCP-1) to enhance AM's anti-bacterial immunity through a lipid raft- mediated mechanism. We have formulated this hypothesis based on our recent findings that both AECII and AM participate in innate immunity against PA. We further found that membrane lipid rafts may be instrumental for regulating cytokine secretion. Using our primary cell model, we have discovered an immune role of AECII in enhancing AM's immunity using a conditioned AECII medium. Our data also suggest that AECII play a critical role in PA infection by secreting MCP-1 and recruiting the classically activated macrophages (CAM). The rationale is that elucidating how AECII enhance AM immunity will indicate a potential strategy to bolster immunity against PA. Our laboratory is ideally suited for this research, having the relevant expertise in isolation and culture of AECII a well as in lung infection models. We propose the following three specific aims: Specific Aim 1: Define the immune role of AECII cells in secreting cytokines during PA infection. We will identify the source of MCP-1 using in situ hybridization with AECII marker SPC. We will also use primary AECII culture to show MCP-1 as a dominant cytokine. Furthermore, AM and AECII from MCP-1-/- mice will be examined for their decreased immune function against PA infection. We will determine the ability of AECII in recruiting the classically activated macrophages (CAM). Specific Aim 2: Evaluate how lipid rafts regulate MCP-1 secretion in AECII. We will study the underlying mechanism for MCP-1 secretion and hopefully identify the involvement of ceramide-rich membrane microdomains. Acid shingomyelinase will be blocked by siRNA and chemical inhibitors for analyzing sphingolipid hydrolysis during PA early infection. Specific Aim 3: Assess the potential of super-AECII over-expressing MCP-1 in enhancing anti-PA capacity of human AM. We will create super-AECII using retroviral vectors to secrete high levels of MCP-1 and test their host defense in PA infection. We will also demonstrate that human AM can be activated by AECII and that this translational research may imply the clinical value of the immune AECII. This research will be performed by graduate and undergraduate students. Our efforts are expected to substantially advance understanding of this previously unrecognized immune function of AECII in activating AM, and may provide insights into mechanisms of cytokine secretion, with indications in development of novel therapeutics for treating this infection. PUBLIC HEALTH RELEVANCE: P. aeruginosa (PA) is a bacterium that causes severe infections, particularly in immunodeficient individuals who are suffering tuberculosis, cancer, AIDS, severe burns, and cystic fibrosis. Because PA is increasingly resistant to antibiotics, its infection usually leads to a chronic state of persistent inflammatory response. We have made the surprising discovery that MCP-1, a versatile cytokine from alveolar epithelial cells, regulates host defense and inflammatory response in PA infection. We have also noted that lipid rafts may be important for regulating cytokine production. Through secretion of MCP-1, the alveolar epithelial cells may recruit a particular subset of macrophages (i.e., classically activated macrophages) to promptly respond to infection. Studying the immune role of alveolar epithelial cells may provide new insights into the development of novel treatment for PA infection.

描述（由申请人提供）：铜绿假单胞菌（PA）经常感染免疫功能低下的HIV-1、癌症和囊性纤维化（CF）个体。由于PA对抗生素的耐药性越来越强，其感染通常导致严重状态或慢性疾病。 具有持续炎症反应的情况。更好地了解宿主-病原体相互作用可能会提出一种更有效的方法来对抗这种病原体。MCP-1是由肺泡上皮细胞II型（AECII）分泌的主要趋化因子。最近的研究表明AECII在PA感染中的免疫作用，但其潜在机制仍不清楚。我们的长期目标是了解宿主免疫机制，并开发控制呼吸道感染的新策略。本申请的目的是阐明AECII的免疫功能，特别是通过它们分泌细胞因子和激活AM。我们的中心假设是，AECII可以分泌细胞因子（MCP-1），通过脂筏介导的机制，以增强AM的抗菌免疫。我们已经制定了这一假设的基础上，我们最近的研究结果，AECII和AM参与对PA的先天免疫。我们进一步发现，膜脂筏可能有助于调节细胞因子的分泌。使用我们的原代细胞模型，我们已经发现了AECII在使用条件AECII培养基增强AM的免疫中的免疫作用。我们的数据还表明，AECII通过分泌MCP-1和募集经典活化的巨噬细胞（CAM）在PA感染中发挥关键作用。基本原理是阐明AECII如何增强AM免疫力将指示增强对PA的免疫力的潜在策略。我们的实验室非常适合这项研究，在AECII的分离和培养以及肺部感染模型方面具有相关的专业知识。我们提出了以下三个具体目标：具体目标1：确定AECII细胞在PA感染期间分泌细胞因子的免疫作用。我们将使用AECII标记SPC进行原位杂交来鉴定MCP-1的来源。我们还将使用原代AECII培养来显示MCP-1作为优势细胞因子。此外，将检查来自MCP-1-/-小鼠的AM和AECII针对PA感染的降低的免疫功能。我们将确定AECII募集经典活化的巨噬细胞（CAM）的能力。具体目标2：评价脂筏如何调节AECII中MCP-1分泌。我们将研究MCP-1分泌的潜在机制，并希望确定富含神经酰胺的膜微区的参与。酸性鞘磷脂酶将被siRNA和化学抑制剂阻断，用于分析PA早期感染过程中鞘脂的水解。具体目的3：评估过表达MCP-1的super-AECII在增强人AM的抗PA能力中的潜力。我们将使用逆转录病毒载体来分泌高水平的MCP-1，并测试它们在PA感染中的宿主防御。我们还将证明人类AM可以被AECII激活，并且这种翻译研究可能意味着免疫AECII的临床价值。这项研究将由研究生和本科生进行。我们的努力预计将大大推进对AECII在激活AM中的这种先前未被认识的免疫功能的理解，并可能提供对细胞因子分泌机制的见解，并指示开发用于治疗这种感染的新疗法。 公共卫生相关性：铜绿假单胞菌（PA）是一种引起严重感染的细菌，特别是在患有结核病、癌症、艾滋病、严重烧伤和囊性纤维化的免疫缺陷个体中。由于PA对抗生素的耐药性越来越强，其感染通常会导致持续炎症反应的慢性状态。我们已经有了令人惊讶的发现，MCP-1，一种来自肺泡上皮细胞的多功能细胞因子， PA感染中宿主防御和炎症反应。我们还注意到，脂筏可能是重要的调节细胞因子的产生。通过分泌MCP-1，肺泡上皮细胞可以募集特定亚群的巨噬细胞（即，经典活化的巨噬细胞）以迅速响应感染。研究肺泡上皮细胞的免疫作用可能为PA感染的新治疗方法的发展提供新的见解。

项目成果

Structural and Molecular Mechanism of CdpR Involved in Quorum-Sensing and Bacterial Virulence in Pseudomonas aeruginosa.

• DOI: 10.1371/journal.pbio.1002449
• 发表时间: 2016-04
• 期刊: PLoS biology
• 影响因子: 9.8
• 作者: Zhao J;Yu X;Zhu M;Kang H;Ma J;Wu M;Gan J;Deng X;Liang H
• 通讯作者: Liang H

A novel signal transduction pathway that modulates rhl quorum sensing and bacterial virulence in Pseudomonas aeruginosa.

• DOI: 10.1371/journal.ppat.1004340
• 发表时间: 2014-08
• 期刊: PLoS pathogens
• 影响因子: 6.7
• 作者: Cao Q;Wang Y;Chen F;Xia Y;Lou J;Zhang X;Yang N;Sun X;Zhang Q;Zhuo C;Huang X;Deng X;Yang CG;Ye Y;Zhao J;Wu M;Lan L
• 通讯作者: Lan L

Genes as early responders regulate quorum-sensing and control bacterial cooperation in Pseudomonas aeruginosa.

• DOI: 10.1371/journal.pone.0101887
• 发表时间: 2014
• 期刊: PloS one
• 影响因子: 3.7
• 作者: Zhao K;Li Y;Yue B;Wu M
• 通讯作者: Wu M

FIP200 is involved in murine pseudomonas infection by regulating HMGB1 intracellular translocation.

FIP200通过调节HMGB1细胞内易位参与鼠假单胞菌感染。

• DOI: 10.1159/000362954
• 发表时间: 2014
• 期刊: Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology
• 作者: Li Y;Gan CP;Zhang S;Zhou XK;Li XF;Wei YQ;Yang JL;Wu M
• 通讯作者: Wu M

Lyn Delivers Bacteria to Lysosomes for Eradication through TLR2-Initiated Autophagy Related Phagocytosis.

Lyn 将细菌输送至溶酶体，通过 TLR2 启动的自噬相关吞噬作用将细菌消灭。

• DOI: 10.1371/journal.ppat.1005363
• 发表时间: 2016-01
• 期刊: PLoS pathogens
• 影响因子: 6.7
• 作者: Li X;He S;Zhou X;Ye Y;Tan S;Zhang S;Li R;Yu M;Jundt MC;Hidebrand A;Wang Y;Li G;Huang C;Wu M
• 通讯作者: Wu M