Epithelial PLUNC as a determinant of Airway Mucosal Antimicrobial Activity

上皮 PLUNC 作为气道粘膜抗菌活性的决定因素

基本信息

批准号：
8119055
负责人：
Yuanpu Peter Di
金额：
$ 39.84万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-09-05 至 2013-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8119055
关键词：
Amino Acid Motifs Anti-Bacterial Agents Antibiotic Resistance Bacteria Bacterial Infections Biotechnology Bronchitis Carcinoma Cell surface Cells Chronic lung disease Clinical Duct (organ) structure Endotoxins Epithelial Epithelial Cells Epithelium Genes Gland Gram-Negative Bacteria HIV Health Host Defense Host Defense Mechanism Human Immune response Immune system In Vitro Incidence Individual Infection Infectious Lung Disorder Intensive Care Units Invaded Knowledge Lactoferrin Leukocytes Liquid substance Lung Lung diseases Maps Mediating Messenger RNA Microarray Analysis Morphology Muramidase Mus Names Nasal Epithelium Natural Immunity Nosocomial Infections Palate Patients Peptides Predisposition Protease Inhibitor Proteins Pseudomonas Pseudomonas aeruginosa Public Health Recombinants Respiratory Tract Infections Secretory Cell Serous Sinusitis Site Specificity Structure-Activity Relationship Terminology Testing Transgenic Mice Tretinoin United States Upper respiratory tract aerosolized airway epithelium alternative treatment antimicrobial antimicrobial drug bactericidal permeability increasing protein base cDNA Arrays cystic fibrosis patients efficacy testing extracellular in vitro activity in vivo killings microbial mucoid neutralizing antibody neutrophil novel pathogen programs prophylactic protein aminoacid sequence respiratory secretory protein small hairpin RNA

项目摘要

DESCRIPTION (provided by applicant): Respiratory infection is the most common lung disease with an estimated incidence of over one billion cases annually in the United States. Gram negative bacteria, particular Pseudomonas aeruginosa, are opportunistic pathogens that frequently cause hospital-acquired infections especially in ventilated patients and are the second most common infection in Intensive Care Units. The conducting airway serves as a first line of defense against bacterial insults through passive action as a barrier as well as through active contribution to antimicrobial activity of the extracellular lining fluid. Importantly, airway epithelial cell-derived proteins contribute to this milieu and promote an appropriate host defense against invading pathogens. Our long-term objective is to advance the understanding of the respiratory innate immune response especially with regard to epithelial cell-specific antimicrobial function. One molecule we believe to be critical to epithelially initiated antimicrobial defense is PLUNC (palate, lung and nasal epithelium carcinoma associated) which we co-discovered and originally named SPURT (secretory protein in upper respiratory tract). We characterized PLUNC as airway lining fluid protein that was secreted apically in primary human airway epithelial cultures and whose abundance was elevated in multiple chronic lung diseases. We demonstrated that PLUNC mRNA and protein in normal subjects were restricted to serous cells of secretory ducts and submucosal glands, sites that express high levels of other host defense proteins such as lysozyme and lactoferrin. PLUNC is abundant in airway fluid of normal individuals and our preliminary results demonstrate that it possess antimicrobial activity against P. aeruginosa. In this study, we hypothesize that mucosal PLUNC acts as an antimicrobial protein that is a critical determinant in host defense against Gram-negative bacteria. To test this hypothesis, we will pursue three specific aims. For Aim 1, the specificity of PLUNC toward common airway pathogens will be assessed and necessity of PLUNC for anti-microbial activity evaluated in vivo and in vitro. For Aim 2, PLUNC transgenic mice and prophylactic administration of recombinant PLUNC will be used to determine if elevated epithelial PLUNC protects against respiratory microbial infection. For Aim 3, the peptide sequences and protein motifs of PLUNC critical to its antimicrobial function will be mapped and utility or these peptides as endogenously generated antimicrobial agents tested. PUBLIC HEALTH RELEVANCE. Relevance to Public Health Concerns: These studies will assess innate mechanisms regulating antimicrobial activity of the airway lining fluid. By focusing on an epithelially-derived protein product, PLUNC, our study may provide an alternative treatment for respiratory infection through augmentation of native host defense mechanisms.

描述（由申请人提供）：呼吸道感染是最常见的肺部疾病，估计在美国每年发病率超过十亿例。革兰氏阴性菌，特别是铜绿假单胞菌，是机会性病原体，经常引起医院获得性感染，尤其是在通气患者中，并且是重症监护病房中第二常见的感染。传导气道通过作为屏障的被动作用以及通过对细胞外衬液的抗菌活性的主动贡献而成为抵御细菌侵害的第一道防线。重要的是，气道上皮细胞衍生的蛋白质有助于这种环境并促进宿主对入侵病原体的适当防御。我们的长期目标是增进对呼吸道先天免疫反应的理解，特别是在上皮细胞特异性抗菌功能方面。我们认为对上皮启动的抗菌防御至关重要的一种分子是 PLUNC（腭、肺和鼻上皮癌相关分子），我们共同发现并最初将其命名为 SPURT（上呼吸道分泌蛋白）。我们将 PLUNC 描述为气道内壁液体蛋白，在原代人气道上皮培养物中顶部分泌，其丰度在多种慢性肺部疾病中升高。我们证明，正常受试者中的 PLUNC mRNA 和蛋白质仅限于分泌管和粘膜下腺的浆液细胞，这些部位表达高水平的其他宿主防御蛋白，如溶菌酶和乳铁蛋白。 PLUNC 在正常个体的气道液体中含量丰富，我们的初步结果表明它对铜绿假单胞菌具有抗菌活性。在这项研究中，我们假设粘膜 PLUNC 作为一种抗菌蛋白，是宿主防御革兰氏阴性菌的关键决定因素。为了检验这一假设，我们将追求三个具体目标。对于目标 1，将评估 PLUNC 对常见气道病原体的特异性，并在体内和体外评估 PLUNC 抗微生物活性的必要性。对于目标 2，PLUNC 转基因小鼠和重组 PLUNC 的预防性施用将用于确定升高的上皮 PLUNC 是否可以防止呼吸道微生物感染。对于目标 3，将绘制对其抗菌功能至关重要的 PLUNC 肽序列和蛋白质基序，并测试这些肽作为内源产生的抗菌剂的用途。公共卫生相关性。与公共卫生问题的相关性：这些研究将评估调节气道内壁液体抗菌活性的先天机制。通过关注上皮衍生的蛋白质产品 PLUNC，我们的研究可能通过增强天然宿主防御机制为呼吸道感染提供替代治疗。