CMV-Induced Embryonic Cochlear Pathogenesis

CMV 诱导的胚胎耳蜗发病机制

• 批准号: 7771092
• 负责人: TINA JASKOLL
• 金额: $ 24.39万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-12-04 至 2011-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7771092
• 关键词: Accounting; Address; Age; Antiviral Agents; Antiviral Therapy; Biological Assay; Biological Models; Biological Neural Networks; Cell Proliferation; Child; Cochlea; Congenital Abnormality; Cytomegalovirus; Cytomegalovirus Infections; Deterioration; Development; Developmental Gene; Drug Delivery Systems; Embryo; Exhibits; Figs - dietary; First Pregnancy Trimester; Foundations; Future; Gene Expression; Gene Expression Profile; Goals; Hearing; In Situ Hybridization; In Vitro; Individual; Infant; Infection; Investigation; Labyrinthitis; Methods; Modeling; Molecular; Molecular Profiling; Morphogenesis; Morphology; Mus; Newborn Infant; Organ Culture Techniques; Pathogenesis; Pathology; Pharmaceutical Preparations; Phenotype; Prevalence; Probability; Relative (related person); Research; Reverse Transcriptase Polymerase Chain Reaction; Risk; Safety; Screening procedure; Sensorineural Hearing Loss; Series; Severities; Signal Pathway; Signal Transduction; Signaling Molecule; System; Time; Tissues; Variant; Viral; Woman; blastomere structure; cellular targeting; clinically relevant; comparative; congenital cytomegalovirus; design; experience; in utero; in vitro Model; malformation; molecular pathology; molecular phenotype; non-genetic; novel; postnatal; public health relevance; research study; spatiotemporal

DESCRIPTION (provided by applicant): Congenital cytomegalovirus (CMV) infection is the most common non-genetic cause of sensorineural hearing loss (SNHL) in children, accounting for between 20 and 60% of all SNHL. It is estimated that at least 8000 infants born annually in the US will have congenital CMV-induced SNHL, with a significant proportion of these children exhibiting delayed onset and progressive deterioration of hearing after the newborn period. Currently, little is known about the mechanism underlying CMV-induced birth defects. Since in utero CMV infection causes SNHL whereas postnatal infection does not, we postulate that CMV-induced cochlear malformations are caused by viral-induced dysregulation of multiple host (embryonic) cell signaling pathways essential for normal cochlear morphogenesis and that the severity of dysmorphogenesis is time-dependent. We have recently developed a novel mouse embryonic organ culture model of CMV-induced cochlear malformations and demonstrate that active CMV infection of embryonic mouse cochlears in vitro induces severely abnormal cochlear phenotypes and labyrinthitis. Our preliminary results indicate that this novel embryonic mouse cochlear culture model mimics the pathology seen in children with congenital CMV infection. Our objective is to initiate delineation of the molecular pathology of the CMV-induced cochlear abnormalities using our novel in vitro embryonic mouse organ culture model of CMV-induced cochlear malformation. Long-term, our goal is to identify the molecular mechanisms underlying CMV-induced cochlear dysmorphogenesis and identify key cellular targets against which new cochlear- specific, postnatal therapies can be directed. We have designed a series of interrelated experiments to address three Specific Aims. Aim 1: Characterize mCMV-induced changes in embryonic cochlear morphology, histodifferentiation and cell proliferation in vitro. Aim 2: Determine mCMV-induced differences in the gene expression of a focused set of "cochlea-related" signaling molecules. Aim 3: Determine time-dependent differences in the molecular pathology of mCMV-induced cochlear abnormalities. The results of our initial studies will provide a detailed molecular phenotype of CMV-induced cochlear pathology. An informed and rational framework will emerge within which future mechanistic studies may be planned and proposed to identify which cellular signaling pathways are functionally essential for CMV-induced cochlear pathogenesis, and likely putative targets against which new therapies can be directed will emerge. Our in vitro model also has the added translational value of providing a system for initial screening of all classes of new candidate, cochlear-targeted, postnatal anti-CMV drugs, including antivirals. This line of investigation is clinically critical because the prevalence of CMV-induced SNHL is considerable, present antiviral therapies are teratogenic in themselves, and long-term use of current antiviral drugs by infected children present serious safety concerns. PUBLIC HEALTH RELEVANCE: Congenital cytomegalovirus (CMV) infection is the most common non-genetic cause of sensorineural hearing loss (SNHL) in children, accounting for between 20 and 60% of all SNHL. It is estimated that at least 8000 infants born annually in the US will have congenital CMV-induced SNHL. Since little is presently known about the mechanisms underlying CMV-induced abnormalitites, the objective of this project is to initiate delineation of the molecular pathology of the CMV-induced cochlear abnormalities. The ultimate goal of this research is to identify the molecular mechanisms underlying CMV-induced cochlear dysmorphogenesis and identify cellular targets against which new cochlear-specific, postnatal therapies can be directed to ameliorate SNHL due to congenital CMV infection. In addition, our in vitro model has the added translational value of providing an efficient model system for initial screening of all classes of new tissue-targeted drugs for their ability to preclude CMV-induced pathology. This is clinically important because the prevalence of CMV-induced SNHL is considerable, present antiviral therapies are teratogenic in themselves, and long-term use of current antiviral drugs by infected children present serious safety concerns.

描述（由申请人提供）：先天性巨细胞病毒（CMV）感染是儿童感音神经性听力损失（SNHL）最常见的非遗传原因，占所有SNHL的20 - 60%。据估计，美国每年至少有8000名新生儿患有先天性CMV诱导的SNHL，其中相当大一部分儿童在新生儿期后表现出延迟发作和听力进行性恶化。目前，对CMV引起的出生缺陷的机制知之甚少。由于在子宫内CMV感染导致SNHL，而出生后感染没有，我们假设CMV诱导的耳蜗畸形是由病毒诱导的多个主机（胚胎）细胞信号通路的失调所造成的，这些信号通路对正常耳蜗形态发生至关重要，并且畸形的严重程度是时间依赖性的。我们最近开发了一种新的小鼠胚胎器官培养模型CMV诱导的耳蜗畸形，并证明，活跃的CMV感染的胚胎小鼠耳蜗在体外诱导严重异常的耳蜗表型和耳蜗炎。我们的初步结果表明，这种新的胚胎小鼠耳蜗培养模型模仿先天性CMV感染儿童的病理学。我们的目的是开始描绘CMV诱导的耳蜗畸形的分子病理学，使用我们的新的体外胚胎小鼠器官培养模型CMV诱导的耳蜗畸形。从长远来看，我们的目标是确定CMV诱导的耳蜗畸形发生的分子机制，并确定新的耳蜗特异性产后治疗可以针对的关键细胞靶点。我们设计了一系列相互关联的实验来解决三个具体目标。目的1：研究小鼠巨细胞病毒（mCMV）对体外培养的胚胎耳蜗形态、组织分化和细胞增殖的影响。目的2：确定mCMV诱导的一组集中的“耳蜗相关”信号分子的基因表达差异。目的3：确定mCMV诱导的耳蜗异常的分子病理学的时间依赖性差异。我们的初步研究结果将提供一个详细的CMV诱导的耳蜗病理的分子表型。一个明智的和合理的框架将出现在未来的机制研究可以计划和建议，以确定哪些细胞信号通路是CMV诱导的耳蜗发病机制的功能至关重要，并可能推定的目标，新的治疗方法可以针对将出现。我们的体外模型还具有额外的翻译价值，为初始筛选所有类别的新候选、耳蜗靶向的出生后抗CMV药物（包括抗病毒药）提供了一个系统。由于CMV诱导的SNHL的患病率相当高，目前的抗病毒治疗本身具有致畸性，并且受感染儿童长期使用目前的抗病毒药物存在严重的安全性问题，因此该研究具有临床关键意义。 公共卫生相关性：先天性巨细胞病毒（CMV）感染是儿童感音神经性听力损失（SNHL）最常见的非遗传性原因，占所有SNHL的20 - 60%。据估计，在美国每年至少有8000名新生儿患有先天性CMV诱导的SNHL。由于目前对CMV诱导的异常的机制知之甚少，本项目的目的是开始描绘CMV诱导的耳蜗异常的分子病理学。本研究的最终目标是确定CMV诱导的耳蜗畸形发生的分子机制，并确定新的耳蜗特异性的细胞靶点，出生后治疗可用于改善先天性CMV感染引起的SNHL。此外，我们的体外模型具有额外的翻译价值，为所有类型的新组织靶向药物的初始筛选提供了有效的模型系统，以确定其排除CMV诱导的病理的能力。这在临床上很重要，因为CMV诱导的SNHL的患病率相当高，目前的抗病毒治疗本身具有致畸性，感染儿童长期使用目前的抗病毒药物存在严重的安全性问题。