REGULATION OF DENDRITIC CELL-LYMPHOCYTE INTERACTIONS

细胞表面分子的鉴定与表征 在造血系统中提供了对 细胞通讯和这些分子在细胞中的作用 免疫反应的调节。该项目将重点放在 CDNA鉴定的细胞表面糖蛋白HB15的研究 克隆及单抗的制备和鉴定 人物刻画。HB15展示了一种独特的表达模式， 主要在淋巴组织中发现，仅限于细胞 在抗原(Ag)呈递方面很关键。HB15的强表达 已在树突状细胞、朗格汉斯细胞和芦苇上发现 斯特恩伯格细胞。树突状细胞是一种强大的抗原提呈细胞 它们被认为在两者的激活中都很重要 细胞毒和辅助性T细胞。从结构上讲，HB15有一个单一的 免疫球蛋白(Ig)样结构域，提示HB15可能是 在蜂窝通信中很重要。这项研究的目标将是 如下所示：(I)描述…的结构和功能 人类和小鼠Hb15基因产物。最初的工作将 涉及小鼠Hb15基因的分子克隆，以及 人类和小鼠基因结构的测定。鉴定 应预测同源区域的功能重要性 分子，并通过以下方式提供对IG基因保护的洞察 进化论。(2)描述这一现象的表达模式 分子在血液系统和组织细胞恶性肿瘤中的表达，以及在 尤其是霍奇金斯病。树突状细胞培养方法的改进 将利用HB15单抗进行分离和纯化 并应提供一种分类和表征手段 属于树突状细胞家族。间接免疫荧光和 利用HB15mAb进行的流式细胞术分析将用于 树突状细胞对淋巴细胞的贡献 自身免疫性疾病中的激活。(3)刻画 表达HB15的细胞的功能，这些细胞在 免疫功能障碍，以及HB15如何参与 那些细胞。树突状细胞的功能将通过 混合白细胞反应中辅助细胞功能的测定， 而HB15单抗取消这一功能的能力将是 测试过。HB15提供共刺激信号 T细胞的增殖将在体外试验中进行研究。 HB15-Ig融合蛋白的构建和黏附试验 用于鉴定HB15的天然配基。这些研究 将提供全面的努力来理解HB的作用 15在正常和异常淋巴细胞生物学中。他们将做出贡献 树突状细胞的表型和功能特征 细胞及其附属细胞家族成员。一种对 这种分子和它在生物学中所起的精确作用 淋巴细胞的激活将为发育提供基础 调节淋巴细胞活化机制的合理工具 处于免疫失调状态。

The identification and characterization of cell surface molecules in the hematopoietic system provides insight into patterns of cellular communication and the role of these molecules in the regulation of the immune response. This project will focus on the study of HB15, a cell surface glycoprotein identified by cDNA cloning and monoclonal antibody (mAb) production and characterization. HB15 demonstrates a unique pattern of expression, being found primarily in lymphoid tissue, and restricted to cells critical in antigen (Ag)-presentation. Strong expression of HB15 has been identified on dendritic cells, Langerhans cells and Reed- Sternberg cells. Dendritic cells are potent Ag-presenting cells that are believed to be important in the activation of both cytotoxic and helper T cells. Structurally, HB15 has a single immunoglobulin (Ig)-like domain, suggesting that HB15 may be important in cellular communication. The goals of this study will be as follows: (i) To characterize the structure and function of the human and murine HB 15 gene products. The initial work will involve the molecular cloning of the murine cDNA for HB 15, and determination of the human and mouse gene structure. Identification of homologous regions should predict functional importance of the molecule and provide insight into IG gene conservation through evolution. (2) To characterize the expression pattern of this molecule in hematopoietic and histiocytic malignancies, and in particular, in Hodgkins Disease. Improved methods of dendritic cell isolation and purification will be developed using the HB 15 mAb and should provide a means for classification and characterization of the family of dendritic cells. Indirect immunofluorescence and flow cytometry analysis utilizing HB 15 mAb will be used to investigate the contribution of dendritic cells to lymphocyte activation in autoimmune disorders. (3) To characterize the function of the cells that express HB15, the role of those cells in immune dysfunction, and how HB15 is involved in the function of those cells. Dendritic cell function will be measured through assays of accessory cell function in the mixed leukocyte reaction, and the ability of HB15 mAb to abrogate this function will be tested. The ability of HB15 to provide a co-stimulatory signal for T cell proliferation will be investigated in in vitro assays. Construction of HB15-Ig fusion proteins and adhesion assays will be utilized to identify the natural ligand for HB15. These studies will provide a comprehensive effort to understand the, role of HB 15 in normal and abnormal lymphocyte biology. They will contribute to the phenotypic and functional characterization of dendritic cells and their accessory cell family members. An understanding of this molecule and the precise function it serves in the biology of lymphocyte activation will provide the basis for developing rational tools to modulate the mechanisms of lymphocyte activation in states of immune dysregulation.