Human B1-like Cells and Pneumococcal Defense in the Elderly

人类 B1 样细胞和老年人的肺炎球菌防御

基本信息

批准号：
10553643
负责人：
THOMAS L ROTHSTEIN
金额：
$ 37.75万
依托单位：
WESTERN MICHIGAN UNIV SCHOOL OF MEDICINE
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：
2019-02-01 至 2025-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10553643
关键词：
Address Adoptive Transfer Age Aging Antibodies Antibody Repertoire Antigens Attention B-Lymphocytes Bacteria Binding Biological Assay Cell Count Cell Separation Cell physiology Cell secretion Cells Characteristics Cloning Communicable Diseases Diagnosis Elderly Enzyme-Linked Immunosorbent Assay Failure Flow Cytometry Functional disorder Future Genetic Transcription Human Immune Immune System Diseases Immunity Immunization Immunoglobulin M Immunoglobulins Individual Infection MS4A1 gene Modeling Morbidity - disease rate Mus Nature Organism Performance Persons Phosphorylcholine Pneumococcal Infections Pneumococcal vaccine Population Process Reporting Rest Role Serology Serum Severity of illness Specificity Stains Streptococcus pneumoniae System Time Vaccination Vaccines Work age related enzyme linked immunospot assay experimental study immune function improved in vivo microbial mortality natural antibodies novel therapeutic intervention

Address Adoptive Transfer Age Aging Antibodies Antibody Repertoire Antigens Attention B-Lymphocytes Bacteria Binding Biological Assay Cell Count Cell Separation Cell physiology Cell secretion Cells Characteristics Cloning Communicable Diseases Diagnosis Elderly Enzyme-Linked Immunosorbent Assay Failure Flow Cytometry Functional disorder Future Genetic Transcription Human Immune Immune System Diseases Immunity Immunization Immunoglobulin M Immunoglobulins Individual Infection MS4A1 gene Modeling Morbidity - disease rate Mus Nature Organism Performance Persons Phosphorylcholine Pneumococcal Infections Pneumococcal vaccine Population Process Reporting Rest Role Serology Serum Severity of illness Specificity Stains Streptococcus pneumoniae System Time Vaccination Vaccines Work age related enzyme linked immunospot assay experimental study immune function improved in vivo microbial mortality natural antibodies novel therapeutic intervention

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项目摘要

The broad, long term objective of this project is to elucidate the mechanism or mechanisms underlying the relative deficiency of serological immunity in the elderly, with particular attention to human B1-like cells and natural antibodies derived therefrom. The specific focus of the present application is to understand the age- related failure of immune defense against infection with S. pneumoniae, both at rest and after immunization with pneumococcal vaccine. A key mechanism for disposing of infectious pneumococci lies in opsonization by serum antibody, and a principal target for opsonizing antibody is phosphorylcholine (PC). Thus, we will study B cells, particularly B1-like cells, that bind PC and secrete anti-PC antibodies. It is known that human serum contains antibodies against PC, that human B1-like cells recognize PC, and that the total population of human B1-like cells declines with age. But it is not known what happens to PC-binding B1-like cells in older individuals as compared to younger individuals. In mice, where adoptive transfer experiments are possible, serum IgM derived from B1 cells of older mice fails to alter the course of pneumococcal infection in mice lacking antibody, whereas an equal amount of serum IgM from younger mice is effective. This coincides with an age-related change in the underlying nature of mouse B1 cell anti- PC antibodies as transcribed immunoglobulin becomes less germline in sequence. These reports regarding age-related changes in total human B1-like cell number and in mouse B1 cell anti-PC antibody repertoire suggest mechanisms for the failure of pneumococcal defense in older people. We hypothesize that the relative deficiency of serological immunity against PC/pneumococci in older humans, before and after pneumococcal vaccination, is due to one or more of: age-related loss of PC- binding B1-like cells, erosion of B1-like cell anti-PC antibody sequence/repertoire, and dysfunction of PC- binding B1-like cells/poor function of B1-like cell anti-PC antibodies. These characteristics have either never been studied in human B1-like cells or never been examined in antigen-specific human B1-like cells with respect to age. We will determine the validity of our hypotheses through the following aims in which we will compare older vs younger healthy donors, and older donors before and after pneumococcal vaccination. SA1. We will evaluate the level of PC-binding B1-like cells, by immunofluorescent staining for B cell subpopulations and PC-binding, followed by flow cytometry/cell sorting. SA2. We will determine the sequence/repertoire of PC-binding B1-like cell antibodies by single cell PCR followed by sequencing, cloning, and ELISA for specificity. SA3. We will evaluate the function of PC-binding B1-like cells and the antibodies they produce, by determining B1-like cell secretion with ELISPOT assays and determining anti- pneumococcal function with opsonophagocytic assays. This work will provide completely new information that will suggest new ways to improve anti-pneumococcal antibody immune defense in the elderly.

该项目的广泛长期目标是阐明该项目的机制或机制最古老的血清学免疫相对缺乏，特别注意人类B1样细胞和自然抗体从中得出。本应用的具体重点是了解年龄 - 免疫防御因肺炎链球菌感染的相关故障，无论是在休息还是在免疫后与肺炎球菌疫苗。处置感染性肺炎球菌的关键机制在于调整通过血清抗体和调向抗体的主要靶标是磷酸胆碱（PC）。那我们会的研究B细胞，特别是B1样细胞，结合PC并分泌抗PC抗体。众所周知，人血清含有针对PC的抗体，人类B1样细胞已识别 PC，人类B1样细胞的总人群随着年龄的增长而下降。但不知道会发生什么与年轻个体相比，老年人的PC结合B1样细胞。在接管的老鼠中转移实验可能是可能的，源自老鼠的B1细胞的血清IgM无法改变缺乏抗体的小鼠中的肺炎球菌感染，而年轻的血清IgM相等小鼠有效。这与小鼠b1细胞抗 - 的潜在性质发生变化相吻合作为转录的免疫球蛋白的PC抗体在顺序上变得较少。这些报告很重要与年龄相关的人类B1样细胞数和小鼠B1细胞抗PC抗体库的变化提出了老年人肺炎球菌防御失败的机制。我们假设血清学免疫对PC/PC/肺炎球菌的相对缺乏症人类在肺炎球菌疫苗接种之前和之后是由于一个或多个：与年龄相关的PC-丧失结合B1样细胞，B1样细胞抗PC抗体序列/曲目的侵蚀以及PC-功能障碍结合B1样细胞/B1样细胞抗PC抗体的功能不良。这些特征从来没有在人类B1样细胞中研究或从未在抗原特异性的人B1样细胞中检查尊重年龄。我们将通过以下目标确定我们的假设的有效性比较年龄较大的健康捐助者，以及肺炎球菌疫苗接种前后的年长捐助者。 SA1。我们将通过对B细胞的免疫荧光染色评估PC结合B1样细胞的水平亚群和PC结合，然后进行流式细胞仪/细胞分类。 SA2。我们将确定单细胞PCR的PC结合B1样细胞抗体的序列/曲目，然后进行测序，克隆和特异性ELISA。 SA3。我们将评估PC结合B1样细胞的功能和通过用ELISPOT分析确定B1样细胞分泌并确定抗抗体，它们产生的抗体肺炎球菌功能带有核细胞测定。这项工作将提供全新的信息这将提出新的方法来改善抗巨球菌抗体免疫防御。