Preterm birth, lung innate immunity, and RSV

早产、肺部先天免疫和 RSV

• 批准号: 6965619
• 负责人: Mark R Ackermann
• 金额: $ 22.96万
• 依托单位: IOWA STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-08-15 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6965619
• 关键词: RNA interference; alveolar macrophages; cell differentiation; cell proliferation; defensins; dendritic cells; disease /disorder proneness /risk; gene expression; gene expression profiling; genetic susceptibility; genetic transcription; gestational age; immunity; immunogenetics; newborn animals; premature infant animal; protein quantitation /detection; pulmonary surfactants; respiratory epithelium; respiratory infections; respiratory syncytial virus; sheep; tissue /cell culture; toll like receptor

DESCRIPTION (provided by the applicant): Respiratory syncytial virus (RSV) infection is the most common cause of respiratory disease leading to hospitalization in children. Preterm infants are especially susceptible to severe RSV infection. Respiratory epithelium is an initial site of RSV infection and epithelial cells along with alveolar macrophages (AM) and dendritic cells (DC) are vital to innate and adaptive immune responses. However, the extent of innate immune gene expression by epithelia and AM-DC in preterm infants can be variable/limited. The hypothesis is that: Reduced innate immunity by respiratory epithelia and AM-DC preterm enhances susceptibility to RSV infection This hypothesis is based on the facts above and our preliminary data in lambs demonstrating limited expression of surfactant proteins A and D (SP-AD), sheep beta-defensin-1 (SBD-1), and Toll-like receptor 4 (TLR4) preterm. It will be tested in preterm lambs which have close similarities with human disease including susceptibility, lesions, and innate immunity. Specific Aim 1 compares expression of key innate immune genes (SBD-1, SP-AD, TLR4) and protein/peptide production in vivo as well as AM-DC cytokine expression in pre- and full-term lung. It also tests the hypothesis that limited epithelial cell proliferation and/or differentiation pre-term underlie(s) the mechanistic basis for limited SP-AD, SDB-1 expression and tests this by comparing transcriptional activity, protein/peptide production in pre- and full term cultured cells with or without cell proliferation and differentiation. Specific Aim 2 tests the hypothesis that SP-AD, SBD-1 and AM-DC responses to RSV are less at pre- than full-term in the lamb model and in vitro with cultured epithelial cells. A second hypothesis, that increased cell proliferation and/or differentiation of epithelia protects against RSV infection, will be tested in vitro with treatments from Aim 1. The extent to which SP-AD, SBD-1 directly prevent RSV infection will be tested with RNAi assays. Specific Aim 3 tests the hypothesis that yet other innate immune genes expressed with cell proliferation/differentiation prevent RSV infection. This Aim uses gene expression profiling of primary polarized human lung cells and a respiratory epithelia-specific probe set (Unigene) that is the most well-annotated and defined gene target set to date. It also identifies ovine orthologs of human genes and test for impaired/reduced expression preterm. This team combines veterinary and human medical expertise to attain the goal of this project: to discover the reason(s) for inadequate expression of SP-AD, SBD-1 and other innate immune genes as well as AMDC responses at preterm that predispose to RSV infection. The work is significant because it discovers the underlying basis for RSV susceptibility preterm and mechanistic approaches to enhance innate immunity.

描述（由申请人提供）：呼吸道合胞病毒（RSV）感染是导致儿童住院治疗的最常见原因。早产儿特别容易受到严重的RSV感染。呼吸上皮是RSV感染的初始部位，以及上皮细胞以及肺泡巨噬细胞（AM）和树突状细胞（DC）对先天和适应性免疫反应至关重要。但是，早产儿中上皮和AM-DC先天免疫基因表达的程度可能是可变/有限的。假设是：通过呼吸性上皮症和AM-DC早产降低了先天免疫力，增强了对RSV感染的敏感性，该假设基于上述事实和我们在LAMBS中的初步数据，表明表面活性剂蛋白A和D（SP-AD），Sheep beta beta-defensin-1（Sheep beta-defensin-1（Sheep beta-defensin-fefensin-1）（SBBD-1（SBD-1）和TLRRISOR 4（sbd-1）和TLRIKE 4.4它将在与人类疾病（包括易感性，病变和先天免疫力）的早产羔羊中进行测试。特定目标1比较了体内和完整期肺中关键先天免疫基因（SBD-1，SP-AD，TLR4）和蛋白/肽的产生以及AM-DC细胞因子表达的表达。它还检验了以下假设：限制上皮细胞的增殖和/或分化前基础（s）有限的SP-AD，SDB-1表达的机理基础，并通过比较或没有细胞增殖和分化的有或没有任何不带有或没有细胞增殖的前培养细胞中的转录活性，蛋白质/肽的产生，蛋白质/肽的产生，蛋白质/肽的产生。具体目标2检验了以下假设：SP-AD，SBD-1和AM-DC对RSV的响应在羔羊模型中的前期和培养的上皮细胞的体外较少。第二个假设，即增加细胞增殖和/或分化可预防RSV感染的假设将在AIM 1的处理中进行体外测试。SP-AD，SBD-1直接防止RSV感染的程度将通过RNAI分析进行测试。具体目标3检验了以下假设：其他用细胞增殖/分化表达的先天免疫基因可以预防RSV感染。此目的使用原发性极化人肺细胞的基因表达分析和呼吸性上皮特异性探针集（Unigene），该探针集（Unigene）是迄今为止最通道和定义的基因靶标。它还鉴定了人类基因的椭圆形直系同源物，并测试了表达早产的受损/降低。该团队结合了兽医和人类的医学专业知识，以实现该项目的目标：发现SP-AD，SBD-1和其他先天免疫基因表达不足的原因，以及以早产的AMDC反应，使RSV感染易感性。这项工作很重要，因为它发现了RSV敏感性早产和增强先天免疫力的机理方法的基本基础。