Modulation of Autoimmune Diabetes by N-acetyl-D-glucosamine Specific B cells

N-乙酰基-D-葡萄糖胺特异性 B 细胞对自身免疫性糖尿病的调节

• 批准号: 7545226
• 负责人: Brian Leonard Dizon
• 金额: $ 3.28万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7545226
• 关键词: Acetylglucosamine; Affect; Antibodies; Antibody Formation; Antigen Presentation; Antigens; Autoantibodies; Autoantigens; Autoimmune Diabetes; Autoimmune Diseases; B cell repertoire; B-Lymphocytes; Beta Cell; Binding; Biological Assay; Blood Glucose; Blood Vessels; C57BL/6 Mouse; Cell Line; Cells; Childhood; Data; Defect; Development; Diabetes Mellitus; Diagnosis; Disease; Drug or chemical Tissue Distribution; Early Diagnosis; Enzyme-Linked Immunosorbent Assay; Epidemiologic Studies; Epitopes; Flow Cytometry; Frequencies; Genetic; Goals; Gram-Positive Bacteria; Heating; Heavy-Chain Immunoglobulins; Human; Immune; Immune system; Immunization; Immunofluorescence Microscopy; Immunoglobulin Idiotypes; Immunoglobulin M; Inbred C57BL Mice; Inbred NOD Mice; Incidence; Individual; Infection; Infectious Agent; Insulin; Insulin-Dependent Diabetes Mellitus; Islets of Langerhans; Lead; Link; Lymphoid; Measurement; Measures; Modeling; Mouse Strains; Mus; Neonatal; Neurologic; Non obese; Numbers; Peripheral; Phenotype; Preparation; Prevention; Production; Proteins; Publishing; Rattus; Resistance; Role; Serum; Streptococcal Infections; Streptococcal Preparation OK-432; Streptococcus pyogenes; Streptozocin; Stress; T-Lymphocyte; Techniques; Testing; Transgenic Mice; Transgenic Organisms; Whole Blood; base; blood glucose regulation; cell type; cohort; diabetic; enzyme linked immunospot assay; improved; in vivo; insight; islet; killings; male; mouse model; pathogen; response

DESCRIPTION (provided by applicant): Type 1 diabetes (T1D) is an autoimmune disease in which insulin-producing beta cells are destroyed by the immune system. The consequence of beta cell destruction is an inability to regulate blood glucose levels, which ultimately lead to neurological and vascular complications. The long-term goal of this project is to identify factors that can influence the progression of T1D in susceptible individuals, which may improve T1D diagnosis and therapy. We will examine a role for Group A Streptococcal (GAS) infection in modulating the function of antigen-specific B lymphocytes in mouse models of autoimmune diabetes. B lymphocytes recognizing beta cell antigens can promote autoimmune diabetes development. In response to GAS challenge, B lymphocytes produce a large proportion of antibodies recognizing O-linked N-acetyl-D- glucosamine, which can bind self-antigens on beta cells. Interestingly, a strong negative correlation between childhood GAS infection and T1D has been demonstrated in human epidemiological studies, while challenge with a heat-killed GAS preparation leads to diabetes resistance in susceptible mouse and rat models. In fact, the diabetes resistance can be transferred by sera from mice immunized with heat-killed GAS to unimmunized mice, suggesting that factors in the sera, such as antibodies, can protect against T1D development. We hypothesize that infection with GAS can protect as well as promote the development of autoimmune diabetes through mechanisms involving GlcNAc-specific B lymphocytes. To test our hypothesis, we propose the following specific aims: 1) to characterize the response of GlcNAc-specific B cells in autoimmune diabetes, 2) to determine how neonatal GAS challenge affects the development of autoimmune diabetes, and 3) to identify mechanisms by which GlcNAc-specific B cells influence the development of autoimmune diabetes. We will measure diabetes incidence in GAS-immunized and unimmunized wild type (WT) NOD mice, streptozotocin (STZ) treated WT C57BL/6 mice, and STZ-treated C57BL/6 mice transgenic for immunoglobulin'heavy chain (IgH Tg) associated with GlcNAc recognition. The absolute numbers, phenotype, and tissue distribution of GlcNAc-specific B cells, as well as GlcNAc-specific IgM titers, will be measured by flow cytometry, ELISA, ELISPOT, and immunofluorescence microscopy utilizing clonal idiotype markers. This study will attempt to determine how a common infectious organism, Group A Streptococcus, can alter an individual's propensity to develop type I diabetes (T1D). Understanding the mechanisms involved in this link may provide insight on new strategies for earlier diagnosis, treatments, and prevention of T1D.

描述（由申请人提供）：1型糖尿病（T1 D）是一种自身免疫性疾病，其中产生胰岛素的β细胞被免疫系统破坏。β细胞破坏的后果是无法调节血糖水平，最终导致神经和血管并发症。该项目的长期目标是确定可能影响易感个体T1 D进展的因素，这可能会改善T1 D的诊断和治疗。我们将研究A组链球菌（GAS）感染在调节自身免疫性糖尿病小鼠模型中抗原特异性B淋巴细胞功能中的作用。识别β细胞抗原的B淋巴细胞可促进自身免疫性糖尿病的发展。响应于GAS攻击，B淋巴细胞产生大比例的识别O-连接的N-乙酰基-D-葡糖胺的抗体，其可以结合β细胞上的自身抗原。有趣的是，在人类流行病学研究中已经证明了儿童期GAS感染与T1 D之间的强烈负相关性，而用热灭活GAS制剂的挑战导致易感小鼠和大鼠模型的糖尿病抗性。事实上，糖尿病抗性可以通过来自用热灭活GAS免疫的小鼠的血清转移到未免疫的小鼠，这表明血清中的因子，如抗体，可以防止T1 D的发展。我们假设GAS感染可以通过涉及GlcNAc特异性B淋巴细胞的机制保护以及促进自身免疫性糖尿病的发展。为了验证我们的假设，我们提出了以下具体目标：1）描述自身免疫性糖尿病中GlcNAc特异性B细胞的反应，2）确定新生儿GAS激发如何影响自身免疫性糖尿病的发展，3）确定GlcNAc特异性B细胞影响自身免疫性糖尿病发展的机制。我们将测量GAS免疫的和未免疫的野生型（WT）NOD小鼠、链脲佐菌素（STZ）处理的WT C57 BL/6小鼠和STZ处理的与GlcNAc识别相关的免疫球蛋白重链（IgH Tg）转基因的C57 BL/6小鼠中的糖尿病发病率。将通过流式细胞术、ELISA、ELISPOT和利用克隆独特型标志物的免疫荧光显微镜测量GlcNAc特异性B细胞的绝对数量、表型和组织分布，以及GlcNAc特异性IgM滴度。这项研究将试图确定一种常见的传染性微生物，A组链球菌，如何改变个体发展为I型糖尿病（T1 D）的倾向。了解这种联系所涉及的机制可能会为T1 D的早期诊断，治疗和预防提供新的策略。