MOLECULAR BASIS OF POLYCLONAL LYMPHOCYTE ACTIVATION

多克隆淋巴细胞激活的分子基础

• 批准号: 3297505
• 负责人: ROBERT DEANS
• 金额: $ 10.07万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-04-01 至 1991-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3297505
• 关键词: B lymphocyte; alleles; chromosome translocation; fluorescent dye /probe; gene expression; genetic library; hybrid cells; immune tolerance /unresponsiveness; immunochemistry; laboratory mouse; laboratory rabbit; leukocyte activation /transformation; linkage mapping; lipopolysaccharides; membrane proteins; molecular cloning; monoclonal antibody; mutant; nucleic acid sequence; protein structure; tissue /cell culture

This is a proposal to study the regulation of B lymphocyte activation at the molecular level, and particularly to gain insight into control mechanisms governing cell proliferation. A major focus of this study is the identification of the gene product defective in a lipopolysaccharide (LPS) non-responsive mouse line. This inbred of mice, C3H//HeJ, is genetically deficient in LPS- induced polyclonal spleen cell activation. This recessive mutation maps to a single locus (lps) on mouse chromosome 4. It is our long range goal to identify this gene and its product, and ultimately to restore competency for LPS responsiveness in mutant lymphocytes by gene re-introduction. Resting splenic lymphocytes respond to a variety of cell surface stimulation by undergoing general metabolic activation, maturation of immunoglobulin production from a surface receptor to a secreted molecule, and entry into the cell cycle. LPS is a potent polyclonal (antigen-independent) B cell activator, stimulating a high proportion (30%) of splenic B cells. B cell responses induced by LPS have common pathways of metabolic and cellular responses exhibited by antigen-induced B cell activation, and these events are currently poorly characterized at the molecular level. We have identified immunochemically a molecule (p-lps) which is unique to LPS-responsive B cells, and absent in LPS non- responsive B cells or spleen cells from C3H/HeJ mice. We have generated monoclonal antibodies (MoAb) which recognize this molecule, and use these antibodies to successfully screen a spleen cell gtII cDNA library. We propose to rigorously test these cDNA clones for their linkage to the lps allele by several distinct strategies. These anti-p-lps MoAb are valuable reagents to use in biochemically characterizing the p-lps molecule. We will determine its pattern of expression in various tissues and lymphocyte subpopulations. As well, we will study potential modification, both post-transcriptionally and post-LPS stimulation. We will investigate the association of p-lps with other molecules, with a particular focus on determining the involvement of p-lps in signal transduction pathways operating in B cell activation. The study of the lps gene and its product will yield insight into the molecular basis by which B cells are activated and lymphocyte proliferation responses induced in the immune response. This contributes to studies on abnormal B cell growth control in autoimmunity or neoplastic disease. This is a model system for an approach of gene complementation to restore inherited immune defects.

这是一项研究B淋巴细胞调节的建议 分子水平上的激活，特别是为了获得洞察力 转化为控制细胞增殖的机制。一位少校 本研究的重点是基因产物的鉴定。 在脂多糖(LPS)无反应小鼠品系中存在缺陷。 这种近亲繁殖的小鼠，C3H//Hej，在基因上缺乏内毒素- 诱导多克隆脾细胞活化。这种隐性突变 映射到小鼠4号染色体上的单个基因座(LP)。这是我们的长染色体 范围目标，以确定该基因及其产物，并最终 在突变体中恢复对内毒素应答的能力 通过基因重新导入淋巴细胞。 静息的脾淋巴细胞对多种细胞表面产生反应 通过进行全身代谢激活来刺激， 从表面受体产生免疫球蛋白的成熟 与分泌的分子结合，进入细胞周期。LP是一种 有效的多克隆(非抗原依赖)B细胞激活剂， 刺激高比例(30%)的脾B细胞。B细胞 脂多糖诱导的反应有共同的代谢途径 抗原诱导的B细胞表现出的细胞反应 激活，目前这些事件的特征很差 分子水平。 我们已经用免疫化学方法鉴定了一种分子(p-LPs)，它是 为内毒素反应性B细胞所特有，而在内毒素非 C3H/HeJ小鼠的反应性B细胞或脾细胞。我们有 产生了识别这一点的单抗(摩押) 分子，并使用这些抗体成功地筛查脾 细胞gtII基因文库。我们建议严格测试这些cdna。 与Lps等位基因连锁的几个不同的克隆 战略。 这些抗p-LPs摩押是很有价值的试剂 P-LPS分子的生物化学特征。我们会 确定其在不同组织中的表达模式 淋巴细胞亚群。此外，我们还将研究潜在的 转录后修饰和脂多糖修饰 刺激。我们将调查p-LP与 其他分子，特别关注于确定 P-LPs参与细胞内信号转导途径的研究 B细胞活化。 对LPs基因及其产物的研究将使我们深入了解 B细胞活化的分子基础与淋巴细胞 在免疫反应中诱导增殖反应。这 对B细胞异常生长控制的研究有贡献 自身免疫或肿瘤性疾病。这是一个模型系统，用于 基因互补恢复遗传免疫的途径 缺陷。