Cell migration and cell-cell interactions in bone marrow

项目3将继续研究骨髓（BM）中的细胞运输。使用活体显微镜 (IVM)，该项目的先前工作已经显示了BM微血管中的特化内皮细胞（EC） 控制血细胞进出血管外空间的选择性运输。 目的1将描述骨髓中T细胞与树突状细胞（DC）相互作用的性质和后果。 这一目的是基于这样的假设，即BM是T细胞和专职抗原呈递的聚集场所。 可以促进抗原特异性细胞免疫应答的诱导的细胞。我们已经表明 最近，BM是CDS T细胞，特别是中央记忆细胞的储存库和募集场所 （Tcm）。初步数据表明，DC可以从外周组织迁移到BM，这表明DC是一种潜在的免疫调节剂。 诱导对BM中外周抗原的初次和二次免疫应答的机制。 然而，目前还不知道这种免疫应答是如何在单细胞水平上诱导的，以及免疫应答是如何在单细胞水平上诱导的。 BM中的反应不同于次级淋巴组织中的反应。Subaim 1.1将决定 DC亚群被募集到BM并表征BM内归巢的DC的迁移行为。这 将包括浆细胞样DC（PDCs）的分析，这将在一种新的转基因小鼠品系中进行研究， 哪些PDCs表达GFP。我们将与德尼莎瓦格纳合作，进行初步观察， 组织驻留PDC激活TNF-α转化酶（TACE）。Subaim 1.2将生成深入的 分析幼稚T细胞与BM中不同DC亚群的相互作用和子目标1.3将扩展这一点。 分析以探索BM居民Tcm的DC介导的回忆反应。作者：Leslie Silberstein 我们将调查是否差异CXCR 4信号是负责初步发现，不同的 白细胞亚群在归巢到BM后具有不同的滞留动力学。Subaim 1.4将探索T细胞 BM中的活化诱导细胞毒性效应细胞（CTL）以及CTL如何在该器官中起作用。统称 目的1中的实验将阐明含有T细胞和/或DC的血细胞输注如何影响细胞增殖， BM中的免疫力。 目的2将继续研究多发性骨髓瘤（MM）在BM中的播散机制。这一目标将 还研究了CTL介导的MM免疫治疗的潜力，MM是一种高度侵袭性的浆细胞来源的肿瘤。 肿瘤具有明显的BM向性。肿瘤细胞被认为是在生殖中心反应中产生的， 次级淋巴器官，并且必须通过血液回到BM以建立疾病。的准备工作 这一目的已经建立了一种体内模型来研究MM在鼠BM中的迁移和生长。Subaim 2.1将 探讨MM细胞在骨髓中播散的分子和细胞机制。Subaim 2.2将继续 初步观察表明CXCR 4-CXCL 12途径对于存活和/或 BM中MM细胞的增殖。这项工作将与Leslie Silberstein合作完成。最后， 子目标2.3将探索基于T细胞的抗MM免疫疗法的可行性， 在这个项目中以前产生的技术。这一目标将产生新的信息， 输血医学和血液学/肿瘤学治疗MM的临床方法。

Project 3 will continue investigations of the cellular traffic in the bone marrow (BM). Using intravital microscopy (IVM), previous work in this project has shown how specialized endothelial cells (EC) in BM microvessels control the selective transit of blood cells into and out of the extravascular space. Aim 1 will characterize the nature and consequences of T cell interactions with dendritic cells (DCs) in the BM. This aim is based on the hypothesis that the BM is a gathering place for T cells and professional antigenpresenting cells that can foster the induction of antigen-specific cellular immune responses. We have shown recently that the BM is a reservoir and site of recruitment for CDS T cells, particularly central memory cells (Tcm). Preliminary data indicate that DCs can migrate from peripheral tissues to the BM, suggesting a potential mechanism for the induction of primary and secondary immune responses to peripheral antigens in the BM. However, it is not known how such immune responses are induced at the single-cell level and how immune responses in the BM differ from those in secondary lymphoid tissues. Subaim 1.1 will determine how different DC subsets are recruited to the BM and characterize the migratory behavior of homed DCs within the BM. This will include an analysis of plasmacytoid DCs (PDCs), which will be studied in a new transgenic mouse strain in which PDCs express GFP. In collaboration with Denisa Wagner, we will pursue preliminary observations that tissue-resident PDCs activate TNF-alpha converting enzyme (TACE). Subaim 1.2 will generate an in-depth analysis of naive T cell interactions with different DC subsets in the BM and subaim 1.3 will extend this analysis to explore DC-mediated recall responses by BM-resident Tcm. In collaboration with Leslie Silberstein we will investigate whether differential CXCR4 signaling is responsible for preliminary findings that different leukocyte subsets have distinct retention kinetics after homing to the BM. Subaim 1.4 will explore if T cell activation in BM induces cytotoxic effector cells (CTLs) and how CTLs function in this organ. Together, the experiments in aim 1 will clarify how blood cell transfusions containing T cells and/or DCs influence cellular immunity in the BM. Aim 2 will continue to study the mechanisms of multiple myeloma (MM) dissemination in the BM. This aim will also investigate the potential for CTL-mediated immunotherapy of MM, a highly aggressive plasma cell-derived tumor with pronounced BM tropism. The tumor cells are thought to arise during germinal center reactions in secondary lymphoid organs and must home via the blood to the BM to establish disease. Preliminary work for this aim has established an in vivo model to study MM migration and growth in murine BM. Subaim 2.1 will explore the molecular and cellular mechanisms of MM cell dissemination in the BM. Subaim 2.2 will pursue preliminary observations indicating that the CXCR4-CXCL12 pathway is critical for the survival and/or proliferation of MM cells in the BM. This work will be done in collaboration with Leslie Silberstein. Finally, subaim 2.3 will explore the feasibility of T cell-based anti-MM immunotherapy building on knowledge and techniques previously generated in this project. This aim will produce novel information that may improve clinical approaches in transfusion medicine and hematology/oncology to the treatment of MM.