Immunotoxic effects of lead on cytokine expression

铅对细胞因子表达的免疫毒性作用

• 批准号: 6702307
• 负责人: David A Lawrence
• 金额: $ 27.76万
• 依托单位: WADSWORTH CENTER
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-03-27 至 2005-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6702307
• 关键词: RNase protection assay; T lymphocyte; biological signal transduction; cellular immunity; cytokine; environmental toxicology; enzyme linked immunosorbent assay; flow cytometry; fluorescence microscopy; gene expression; gene targeting; genetically modified animals; immunofluorescence technique; immunoregulation; immunotoxicity; interferon gamma; interleukin 1; interleukin 4; interleukin 8; laboratory mouse; lead poisoning; leukocyte activation /transformation; macrophage; microarray technology; mutant; polymerase chain reaction; western blottings

DESCRIPTION (provided by applicant): The mechanisms by which lead (Pb) alters immune reactivities are multifactorial, both MHC and non-MHC genes are likely involved, in that there appear to be independent effects on T cells, B cells and macrophages, and these effects appear to involve different cytokines and signaling/transcription factors. The long-term goal of this project is to determine the sub cellular mechanisms by which Pb alters lymphocyte development (naive to memory cells) and the activation and reactivity of memory T cells which could influence immunity causing hypo- or hyper-responsiveness. This proposal tests the hypothesis that the heavy metal Pb can alter immune status by biochemical and molecular modulations resulting in a preferential environment for development of type-2 responses, and dependent on the particular type of immune response needed for defense against an infectious agent, cancer or regulation of self-reactive response, this "skewing" may increase pathologies associated with lessened type-] and enhanced lype-2 immune responses. Synergies between chemical, physical and/or emotional stresses can enhance the skewing of immune reactivities toward type-] or type-2 responses; short-term imbalance is needed for appropriate defenses, but long-term imbalance exacerbates pathologies. Thus, an environmental agent such as Pb may alter the balance enough to increase morbidity. Mutant (genetic over-expressing or deficient) H-2d mice will be employed to assess the involvement of specific genes in the "skewing" phenomenon. Specific questions to be addressed are: how Pb alters kinetic production of IFN?gamma; how macrophage reactivities, such as production of ILl 0, ILl 2 or ILl 8, are altered, and whether cellular thiol modifications are involved; whether Pb "skewing" can be achieved with T cells specific only to OVA or whether T cells with self-reactivity (or metal-related specificities) are needed, whether B cells or a particular type of T cell subset (e.g., NK-like T cells) are required and within what particular cytokine environment; what molecular mechanisms are involved with the IL-4 reactivities of T cells; and what cells are responsible for the type-2 environment induced by Pb. Cell types will be assayed by flow cytometry and immunofluorescence microscopy. The presence of cytokines and signaling factors will be assessed by ELISA, microarray analysis (or RNAse protection) and western analyses. Pb heads the ATSDR list of toxic substances and its potential to induce or modify incidence of diseases associated with immune reactivities needs to be better understood. This cellular and molecular approach should identify the mechanisms by which Pb is immunomodulatory and assist evaluation of its health hazard and the molecular basis for the risks in exposure.

描述(申请人提供)：铅(铅)改变的机制 免疫反应是多因素的，MHC和非MHC基因都有可能 涉及到对T细胞、B细胞似乎有独立的影响 和巨噬细胞，这些效应似乎涉及不同的细胞因子和 信号/转录因子。这个项目的长期目标是 确定铅改变淋巴细胞发育的亚细胞机制 (对记忆细胞的幼稚)和记忆T细胞的激活和反应性 这可能会影响免疫力，导致低或高反应性。这 该提案验证了重金属铅可以改变免疫状态的假设 通过生物化学和分子调控产生了优先的 类型2反应的发展环境，并依赖于 防御传染性疾病所需的特定类型的免疫反应 毒剂、癌症或调节自身反应，这种“偏斜”可能 与减弱的[型]和增强的2型免疫相关的病理增加 回应。化学、物理和/或情绪压力之间的协同效应可以 增强免疫反应性向[型]或2型反应的倾斜； 适当的防御需要短期的不平衡，但长期的 不平衡会加剧病态。因此，诸如铅之类的环境试剂可以 改变平衡足以增加发病率。突变型(基因过度表达 或缺陷)H-2D小鼠将被用来评估特定的 “倾斜”现象中的基因。需要解决的具体问题包括：如何 PB改变干扰素-γ的动态产生；巨噬细胞的反应如何，如 IL0、IL2或IL8的产生被改变，无论是细胞内的硫醇 这涉及到修饰；T细胞能否实现铅的“偏斜” 仅针对OVA或具有自身反应性(或与金属相关)的T细胞 特异性)，无论是B细胞还是特定类型的T细胞 亚群(例如，NK样T细胞)是必需的，在什么特定的细胞因子中 IL-4反应的分子机制是什么 T细胞的数量；以及哪些细胞负责诱导的2型环境 由铅。细胞类型将通过流式细胞仪和免疫荧光进行分析 显微镜。细胞因子和信号因子的存在将通过以下方式进行评估 酶联免疫吸附试验、基因芯片分析(或核糖核酸酶保护)和蛋白质分析。PB磁头 《ATSDR有毒物质清单》及其诱发或修改的可能性 与免疫反应相关的疾病的发病率需要更高 明白了。这种细胞和分子的方法应该能确定这种机制 其中铅具有免疫调节作用，并有助于评估其对健康的危害 暴露风险的分子基础。