Activation Defects in T Cells of Aged Mice

老年小鼠 T 细胞的激活缺陷

• 批准号: 7463678
• 负责人: RICHARD A MILLER
• 金额: $ 30.33万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-09-30 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7463678
• 关键词: Accounting; Address; Adoptive Transfer; Age; Aging; Agonist; Antigen-Presenting Cells; Biochemical; CD44 gene; CD8B1 gene; Calcium Signaling; Cell Aging; Cell physiology; Cell surface; Cells; Chromosome Pairing; Complex; Conjugated Carrier; Cytoskeletal Proteins; Cytoskeleton; Data; Defect; Digestion; Disease; Distal; Elderly; Electrophoresis; Endopeptidases; Enzymes; Failure; Family; Functional disorder; Glycoproteins; Glycoside Hydrolases; Glycosides; Haptens; Immune; Immune response; Immunoblotting; Immunotherapy; In Vitro; Infection; Laboratories; Lead; Lectin; Link; Malignant Neoplasms; Mediating; Membrane Glycoproteins; Methods; Microfluidics; Modeling; Molecular; Mus; Nuclear; Numbers; PTPRC gene; Pattern; Peptide Hydrolases; Peptides; Phosphorylation; Polysaccharides; Predisposition; Protein phosphatase; Publishing; Research Personnel; Reverse Transcriptase Polymerase Chain Reaction; Series; Site; Synapses; System; T-Cell Activation; T-Lymphocyte; Testing; Transferase; Transgenic Organisms; Vaccination; Work; age related; aged; base; cell age; cytokine; extracellular; functional restoration; glycosylation; glycosyltransferase; improved; improved functioning; in vivo; knowledge base; macromolecule; repaired; research study; response; segregation; senescence; synaptogenesis; tumor; two-dimensional

DESCRIPTION (provided by applicant): Prior work has suggested a model for age-related T cell failure in which T cells from aged mice show both altered surface glycoprotein patterns and defects in cytoskeleton-dependent relocalization of surface glycoproteins. In addition, OSGE, a protease specific for O-linked glycoproteins including CD43, CD44, and CD45, has been shown to restore function of aged T cells to levels similar to that of T cells of young donors. Three specific aims will address, respectively, (1) altered glycosylation, (2) cytoskeletal defects, and (3) repair of in vivo immune responses. Aim 1 a will use a battery of specific lectins and glycosidases to determine which T cell surface glycoproteins contribute to diminished synapse formation, calcium signals, and cytokine expression in aged T cells. Aim 1b will use 2D electrophoresis and glycan-profiling to identify the T cell surface glycoproteins whose susceptibility to enzymatic digestion parallels the ability of the enzymes to improve T cell function. Aim 1c uses a multiplex RT-PCR approach to develop a listing of age-related changes in mRNAs for glycosides and glycosyl-transferases. Aim 1 d evaluates specific surface glycoproteins, starting with CD44, CD45, CD4, and CDS, for susceptibility to the functionally relevant enzymes. Aim 2 will explore the molecular basis for the failure of aged T cells to move molecules either into the synapse, or into the distal pole complex (DPC) opposite from the site of APC contact. This aim explores two related hypotheses: (a) that T cell activation defects involve a failure to remove inhibitory molecules, including CD43 and protein phosphatases, from the synapse to the DPC, and (b) that the cytoskeletal defect involves altered phosphorylation of proteins in the ERM family. Aim 3 will use two in vivo adoptive transfer systems to see if enzyme-treated T cells from aged donors show improved function in responses to hapten-carrier conjugates and to transplantable tumors. Improved knowledge of the basis for poor T cell function in old age, and the mechanisms by which enzyme exposure corrects these defects, could point to new ways to protect the elderly from cancer and infection, as well as to improvements in vaccination methods for old people.

描述（由申请人提供）：先前的工作提出了一种与年龄相关的 T 细胞衰竭模型，其中来自老年小鼠的 T 细胞显示出表面糖蛋白模式的改变和表面糖蛋白的细胞骨架依赖性重新定位的缺陷。此外，OSGE 是一种对 O 连接糖蛋白（包括 CD43、CD44 和 CD45）具有特异性的蛋白酶，已被证明可以将衰老 T 细胞的功能恢复到与年轻捐赠者的 T 细胞相似的水平。三个具体目标将分别解决（1）糖基化改变、（2）细胞骨架缺陷和（3）体内免疫反应的修复。目标 1a 将使用一组特定的凝集素和糖苷酶来确定哪些 T 细胞表面糖蛋白导致衰老 T 细胞中突触形成、钙信号和细胞因子表达的减少。目标 1b 将使用 2D 电泳和聚糖分析来鉴定 T 细胞表面糖蛋白，其对酶消化的敏感性与酶改善 T 细胞功能的能力相似。 Aim 1c 使用多重 RT-PCR 方法来开发糖苷和糖基转移酶 mRNA 中与年龄相关的变化列表。目标 1d 评估特定表面糖蛋白（从 CD44、CD45、CD4 和 CDS 开始）对功能相关酶的敏感性。目标 2 将探索衰老 T 细胞无法将分子移动到突触或与 APC 接触部位相对的远端极复合体 (DPC) 的分子基础。该目标探讨了两个相关的假设：(a) T 细胞激活缺陷涉及未能从突触到 DPC 去除抑制分子，包括 CD43 和蛋白磷酸酶，以及 (b) 细胞骨架缺陷涉及突触中蛋白质磷酸化的改变。 ERM 家族。目标 3 将使用两种体内过继转移系统来观察来自老年供体的酶处理 T 细胞在对半抗原载体缀合物和可移植肿瘤的反应中是否表现出改善的功能。提高对老年 T 细胞功能不良的基础以及酶暴露纠正这些缺陷的机制的了解，可能会为保护老年人免受癌症和感染带来新的方法，并改进老年人的疫苗接种方法。