CYTOKINE GENE EXPRESSION BY CD4+ CELLS IN AGING MICE

该项目的长期目标是：i）了解空间 细胞因子基因表达的限制-因此，对细胞 功能-在健康个体的CD 4 +T细胞群内，以及 ii）鉴定老年人的CD 4 + T细胞区室， 个人，可能导致这种现象的变化， 免疫衰老 这里提出使用鼠标系统来 在人CD 4 + T细胞中建立表型和功能异质性模型。 流式细胞荧光技术将用于分析脾脏CD 4 + 来自年轻成年、中年和老年小鼠的细胞， 三种细胞表面决定簇-3G 11、CD 45 RB和CD 44-的表达， 被认为是用有限的模式来划分CD 4+细胞亚群， 细胞因子产生和细胞功能。 随后，CD 4+细胞， 从每个年龄组的小鼠中分离，将用 体外抗CD 3 β单克隆抗体，然后评估：i） 细胞周期进入和进展的程度和ii） 几种T细胞相关细胞因子的产生，在 稳态mRNA积累或蛋白质分泌水平。 在 此外，来自年轻Thy-1同种异型同源小鼠和来自 在细胞中使用适当背景品系的老年小鼠 混合实验研究CD 4 +-CD 4+细胞中与年龄相关的变化 通讯 为了将3G 11、CD 45 RB和 CD 44表达具有CD 4+细胞功能，将分离细胞亚群 基于这些标志物的表达水平，然后评估 刺激依赖性细胞周期进程和细胞因子模式 基因表达。 比较分析将在以下两种情况下进行： 年轻组内的不同子集， 年龄组之间的准备。 最后，细胞混合实验 将扩展到包括子集-子集的评估 来自年轻小鼠的CD 4+细胞之间的通信， 随着小鼠年龄的增长，这些通信发生了变化。 结果 从这些研究中，我们应该进一步了解功能性 健康个体的CD 4+细胞区室的异质性，以及 老龄化对妇女代表性和能力的影响 CD 4+细胞亚群。

The long-term goals of this project are: i) to understand the spatial restrictions on cytokine gene expression - and, consequently, on cell function - within the CD4+T cell population of healthy individuals, and ii) to identify, within, the CD4+ T cell compartment of elderly individuals, alterations which may underlie the phenomenon of immunosenescence. It is proposed herein to use the mouse system to model phenotypic and functional heterogeneity among human CD4+ T cells. Flow cytofluorometric techniques will be used to analyze splenic CD4+ cells from young adult, middle-aged, and old mice for the simultaneous expression of three cell surface determinants - 3G11, CD45RB, and CD44 - thought to demarcate CD4+ cell subsets with restricted patterns of cytokine production and cell function. Subsequently, CD4+ cells, isolated from mice of each age group, will be stimulated with anti-CD3epsilon monoclonal antibody in vitro and then evaluated for: i) extent of cell cycle entry and progression and ii) patterns of production of several T cell-associated cytokines, monitored at the level of either steady-state mRNA accumulation or protein secretion. In addition, CD4+ cells from young Thy-1 allotype congenic mice and from old mice of the appropriate background strain will be used in cell mixing experiments to study age-related alterations in CD4+-CD4+ cell communications. In order to correlate patterns of 3G11, CD45RB, and CD44 expression with CD4+ cell function, cell subsets will be isolated based on the expressed levels of these markers and then evaluated for stimulation-dependent cell cycle progression and patterns of cytokine gene expression. Comparative analyses will be performed both with distinct subsets within the young group and with subset-matched preparations between age groups. Finally, the cell-mixing experiments described above will be extended to include evaluations of subset-subset communications among CD4+ cells from young mice, and potential alterations in these communications with advancing mouse age. Results from these studies should further our understanding of functional heterogeneity in the CD4+ cell compartment of healthy individuals, and of the consequences of aging on the representation and competence of CD4+ cell subsets.