CCR9 and TECK in Intestinal Lymphocyte Trafficking

描述：（申请人的摘要）：趋化因子已经涉及免疫调节。 控制淋巴细胞运输和微环境定位， 正常淋巴细胞再循环和免疫反应期间。这项建议 重点是了解新型趋化因子受体CCR 9及其 化学引诱物配体TECK在肠道免疫中的作用。研究者已 显示CCR 9由循环α 4 J37+的离散子集表达， “肠”记忆T细胞，以及几乎所有的固有层和 小肠上皮内淋巴细胞;其配体TECK 优先由小肠的上皮细胞表达。在这里， 研究者应探索这一受体-配体对的假设 在靶向小肠免疫细胞方面发挥着重要作用， 将粘膜免疫应答与全身免疫应答模式分离（并且可能 甚至是来自大肠免疫反应的小的）。1)表型和 将表征人中CCR 9+淋巴细胞亚群的功能特性 通过流式细胞术和细胞因子测定;以及CCR 9和TECK参与 小鼠肠道淋巴细胞与全身淋巴细胞的趋化反应将 在transwell趋化性测定中进行评估。2)TECK mRNA的细胞位点 表达将通过原位杂交来确定，并且表达的分布将通过原位杂交来确定。 蛋白水平的TECK将通过免疫组织化学在 肠和其他组织。3)研究者应确定CCR 9 + 细胞包括用于肠回忆的循环记忆和/或效应细胞 抗原，使用轮状病毒的免疫反应，一个良好的特点小 肠道病原体作为模型。T细胞记忆应答的体外测定， B细胞的抗原结合测定，以及小鼠体内免疫测定， 将用于表征轮状病毒特异性B和T淋巴细胞， CCR 9的表达。4)最后，探讨了CCR 9和TECK在细胞生理过程中的作用。 淋巴细胞向肠的运输将通过原位免疫组织化学法进行评价。 视频显微镜，重点是他们假设的参与， 渗出拟议的研究将严格界定CCR 9的重要性， 及其配体TECK用于淋巴细胞归巢至小肠板 固有的，它们在分离肠道免疫应答中的作用，以及它们的 作为炎症性肠病治疗靶点的潜力。

DESCRIPTION: (Applicant's Abstract): Chemokines have been implicated in the control of lymphocyte trafficking and microenvironmental positioning during normal lymphocyte recirculation, and during immune responses. This proposal focuses on understanding the role of the novel chemokine receptor CCR9 and its chemoattractant ligand TECK in the intestinal immunity. The investigator has shown that CCR9 is expressed by a discrete subset of circulating a4J37 + "intestinal" memory T cells, and by almost all lamina propria and intraepithelial lymphocytes in the small intestines; and that its ligand TECK is preferentially expressed by epithelial cells of the small intestines. Here, the investigator shall explore the hypothesis that this receptor-ligand pair plays a fundamental role in targeting small intestinal immune cells, helping to segregate mucosal from systemic immune response modalities (and potentially even small from large intestinal immune responses). 1) The phenotype and functional properties of CCR9+ lymphocyte subsets in man will be characterized by flow cytometric and cytokine assays; and the involvement of CCR9 and TECK in the chemotactic responses of intestinal vs. systemic lymphocytes in mice will be assessed in transwell chemotaxis assays. 2) The cellular sites of TECK mRNA expression will be defined by in situ hybridization, and the distribution of TECK at the protein level will be explored by immunohistochemistry in intestines and other tissues. 3) The investigator shall determine whether CCR9+ cells comprise circulating memory and/or effector cells for intestinal recall antigens, using the immune response to rotavirus, a well characterized small intestinal pathogen, as a model. In vitro assays of T cell memory responses, antigen-binding assays of B cells, and in vivo assays of immunity in the mouse, will be used to characterize rotavirus-specific B and T lymphocytes and assess their expression of CCR9. 4) Finally, the role of CCR9 and TECK in physiologic lymphocyte trafficking to the intestines will be evaluated by in situ videomicroscopy, focusing on their hypothesized involvement in transendothelial diapedesis. The studies proposed will define critically the importance of CCR9 and its ligand TECK for homing of lymphocytes to the small intestinal lamina propria, their role in segregating intestinal immune responses, and their potential as therapeutic targets in inflammatory bowel diseases.