Rotavirus Outer Capsid Functions in Neutralization

轮状病毒外衣壳的中和功能

基本信息

批准号：
9808756
负责人：
Kristen M Ogden
金额：
$ 21.25万
依托单位：
VANDERBILT UNIVERSITY MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-05-20 至 2021-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9808756
关键词：
Academic Medical Centers Amino Acid Sequence Animal Model Animals Antibodies Antibody Response Antigenic Diversity Antigens Attenuated Binding Biological Biological Assay Capsid Capsid Proteins Cell Line Cell model Cells Child Cultured Cells Data Developing Countries Development Diarrhea Dose Engineering Enterocytes Epidemic Epitopes Evolution Exhibits Foundations Genes Genetic Genome Genotype Geographic Locations Human Human Cell Line Immune response Immune system Immunize Immunologic Tests Immunologics In Vitro Individual Infant Infection Intestines Knowledge Laboratories Mediating Modeling Molecular Biology Molecular Vaccines Monkeys Morbidity - disease rate Oryctolagus cuniculus Outcome Pathogenicity Pattern Phenotype Plasmids Play Population Analysis Population Dynamics Proteins Publishing Reporting Research Resources Role Rotavirus Rotavirus Vaccines Rotavirus disease Serotyping Serum Specificity Specimen System Technology Testing Tropism Vaccinated Vaccination Vaccines Viral Virion Virus Work base burden of illness cell type diarrheal disease experimental study human model improved insight kidney cell kidney epithelial cell mortality neutralizing antibody population based pressure prevent programs protein function response reverse genetics uptake vaccine development vaccine efficacy vaccine evaluation vaccine response

项目摘要

PROJECT SUMMARY Rotavirus is an important cause of diarrheal morbidity and mortality in infants and children, particularly in developing countries. The rotavirus outer capsid is composed of VP4 and VP7 proteins, which facilitate viral attachment and entry and are primary targets of neutralizing antibodies. Rotaviruses exhibit narrow species and cell tropism, with human rotaviruses growing poorly in most cell lines and animal models. This phenotype, to which VP4 contributes significantly, has hampered studies of human rotavirus molecular biology and vaccine development. Following rotavirus vaccine introduction, there has been a significant decrease in severe rotavirus disease but concurrent emergence and spread of previously uncommon rotavirus serotypes and continued evolution of common serotypes. Differential patterns of circulating rotavirus serotypes that correlate with the specific vaccine implemented in a geographic region have been reported, suggesting vaccine- mediated serotype selection. While the antigenic diversity of contemporary and emerging human rotaviruses suggests antibodies elicited by current vaccines may neutralize them inequivalently, neutralization has not yet been empirically tested. The recent development of a plasmid-based reverse genetics system for a simian rotavirus and the use of human intestinal enteroids to culture human rotaviruses present new opportunities to elucidate outcomes of interactions between rotavirus outer-capsid antigens and vaccine-elicited antibodies. To test the hypothesis that that outer-capsid antigenic diversity, vaccine, and cell type influence serum neutralization of human rotaviruses, we propose two integrated Subaims. In Subaim 1, we will engineer chimeric simian rotaviruses incorporating outer-capsid genes from contemporary and emerging pathogenic human strains or vaccine strains using reverse genetics. We will quantify the capacity of serum antibodies elicited in rabbits or infants by different rotavirus vaccines to bind and neutralize the engineered viruses using standard assays, to permit comparison with previous studies. By isolating a human G or P type in an otherwise isogenic background, these studies will provide insight into antigen-specific functions of VP7 and VP4 in neutralization. In Subaim 2, we will perform replication and neutralization assays in human cell lines and human intestinal enteroids, using a panel of chimeric rotaviruses and differentially vaccinated rabbit and infant sera. These studies will provide biologically relevant insights into serum antibody responses elicited by different vaccines and roles of VP4 and VP7 in neutralization, which may support models that differ from those proposed based on animal rotaviruses or experiments in animal cell lines. Together, these studies will reveal individual rotavirus outer-capsid antigen functions in neutralization and differences in the breadth and specificity of vaccine-elicited serum antibody responses, provide insight into immunological pressures influencing rotavirus population dynamics, and enable development of improved rotavirus neutralization assays and platforms to test immune responses to current globally circulating rotaviruses.

项目摘要轮状病毒是婴儿和儿童腹泻发病率和死亡率的重要原因，特别是发展中国家。轮状病毒外带CACSID由VP4和VP7蛋白组成，可促进病毒附着和进入，是中和抗体的主要目标。轮状病毒表现出狭窄的物种和细胞向流，在大多数细胞系和动物模型中，人轮状病毒生长较差。这个表型， VP4显着贡献了对人轮状病毒分子生物学和疫苗的研究发展。轮状病毒疫苗引入后，严重的降低显着下降轮状病毒病，但同时出现和以前不常见的轮状病毒血清型和常见血清型的持续演变。相关的循环轮状病毒血清型的差异模式已经报道了在地理区域实施的特定疫苗，这表明疫苗 - 介导的血清型选择。而当代和新兴的人轮状病毒的抗原多样性建议当前疫苗引起的抗体可能将其中和不等，中和尚未经过经验测试。最近开发了基于质粒的反向遗传学系统轮状病毒和人类肠内肠动物在培养人轮状病毒中的使用带来了新的机会阐明轮状病毒外囊抗原与疫苗吸收抗体之间相互作用的结果。为了测试外部抗原抗原多样性，疫苗和细胞类型的假设影响血清人轮状病毒中和，我们提出了两个综合的子iaM。在Subaim 1中，我们将设计嵌合邻生和新兴致病性的嵌合型替代型轮子病毒使用反向遗传学的人菌株或疫苗菌株。我们将量化血清抗体的能力通过不同的轮状病毒疫苗在兔子或婴儿中引起，以结合和中和工程病毒标准测定，以允许与以前的研究进行比较。通过隔离人类或p类型这些研究将提供对VP7和VP4在中和。在Subaim 2中，我们将在人类细胞系中进行复制和中和测定人肠肠to肠肠to使用一组嵌合轮病毒和差异疫苗接种的兔子和婴儿血清。这些研究将提供对由血清抗体反应的生物学相关见解 VP4和VP7在中和中的不同疫苗和作用，这可能支持与这些模型不同的模型根据动物轮状病毒或动物细胞系中的实验提出的提议。这些研究将共同揭示单个轮状病毒外部capsid抗原在中和和广度差异和差异中起作用疫苗吸收的血清抗体反应的特异性，提供了对免疫压力的见解影响轮状病毒种群动力学，并能够开发改善轮状病毒中和测定法和平台测试对当前全球循环轮状病毒的免疫反应。