DNA Damage Repair Pathways Play a Critical Role in Myeloid Differentiation

项目摘要 髓系祖细胞的分化产生多种下游效应细胞， 先天免疫系统的组成部分。在造血过程中，单核细胞作为 监视单元，等待接收来自细胞因子的信号，以识别炎症或感染区域。 分化诱导可能会产生树突状细胞或巨噬细胞，这取决于接收到的信号， 炎症与DNA损伤剂的释放有关， 影响免疫细胞的功能。但是保护分化的效应物的机制 细胞免受DNA损伤的研究相对不足，特别是树突状细胞。所以在这 我们研究DNA损伤和修复如何影响树突状细胞的分化和激活， 细胞我们的初步数据表明，一个主要的缺陷，在核苷酸切除修复（NER）途径， 而其他途径，包括非同源末端连接和碱基切除修复 保持熟练。由于这些途径专门修复不同类型的DNA损伤， 数据提示树突细胞可能对某些DNA损伤剂比其它的更敏感。的 该提案的目标是确定DNA修复在细胞分化和激活过程中的作用， 树突状细胞，并确定NER途径的失调对树突状细胞的能力的影响。 肺部的炎症反应我假设DNA修复在分化中起着关键作用， 和树突状细胞的功能，以及DNA修复的失调降低了树突状细胞的能力， 来激活T细胞为了研究这一点，我将首先确定DNA损伤对分化的影响， 和树突状细胞的激活。通过首先分离人单核细胞，然后用一个面板挑战它们， DNA损伤剂在分化过程中，我将确定如何特定类型的DNA损伤影响， 树突状细胞的分化及其体外活化T细胞的能力。为了确定 DNA修复影响树突状细胞的分化和功能在体内，我将调查小鼠的能力 NER基因XPC缺陷，以在暴露于免疫原性 试剂poly（I：C）。支气管肺泡灌洗液和完整肺中细胞因子和细胞浸润的分析 将使用组织以确定与WT相比树突状细胞和T细胞活化的变化 对照该项目的完成将对DNA损伤和修复的作用产生新的见解， 树突状细胞的分化和功能，并将提供一个基础，了解和可能 控制患者的免疫反应，特别是在促进DNA损伤的条件下， 癌症治疗、炎症和吸入毒物。

PROJECT SUMMARY Differentiation of myeloid progenitor cells produces a wide variety of downstream effector cells that are integral components of the innate immune system. During hematopoiesis, monocytes are produced as surveillance units, waiting to receive signals from cytokines identifying regions of inflammation or infection. Induction of differentiation may produce dendritic cells or macrophages, dependent on the signals received, and inflammatory conditions are associated with the release of DNA damaging agents that could potentially impact the function of immune cells. But the mechanisms involved in protecting the differentiated effector cells from DNA damage is relatively under-investigated, particularly for dendritic cells. Therefore, in this proposal we investigate how DNA damage and repair affect the differentiation and activation of dendritic cells. Our preliminary data indicate a major deficiency in the nucleotide excision repair (NER) pathway in dendritic cells, whereas other pathways, including non-homologous end joining and base excision repair remain proficient. Since these pathways specialize in the repair of different types of DNA damage, these data suggest that dendritic cells may be more sensitive to some DNA damaging agents than others. The goals of this proposal are to determine the role of DNA repair during the differentiation and activation of dendritic cells and to determine the effect of dysregulation of the NER pathway on the ability to mount an inflammatory response in the lung. I hypothesize that DNA repair plays a critical role in the differentiation and the function of dendritic cells and that dysregulation of DNA repair diminishes the ability of dendritic cells to activate T cells. In order to study this, I will first determine the effect of DNA damage on the differentiation and activation of dendritic cells. By first isolating human monocytes and then challenging them with a panel of DNA damaging agents during differentiation, I will determine how specific types of DNA damage affect the differentiation of dendritic cells and their ability of to activate T cells in vitro. To determine how inefficient DNA repair affects dendritic cell differentiation and function in vivo, I will investigate the ability of mice deficient in the NER gene, XPC, to induce an inflammatory response after exposure to the immunogenic agent poly(I:C). Analysis of cytokines and cell infiltrates into the bronchoalveolar lavage fluid and intact lung tissue will be utilized in order to determine the change in dendritic cell and T cell activation compared to WT controls. Completion of this project will yield new insights into the roles of DNA damage and repair in dendritic cell differentiation and function, and will provide a foundation for understanding and possibly controlling immune responses in patients, particularly under conditions that promote DNA damage including cancer therapy, inflammation, and inhaled toxicants.