Thymocyte-Dendritic Cell Interactions near Sources of CCR7 Ligands in the Thymic Cortex
Thymocyte-Dendritic Cell Interactions near Sources of CCR7 Ligands in the Thymic Cortex
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DOI：
10.4049/jimmunol.181.10.7014
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发表时间：
2008-11-15
影响因子：
4.4
通讯作者：
Robey, Ellen A.
中科院分区：
文献类型：
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作者：
Ladi, Ena;Schwickert, Tanja A.;Robey, Ellen A.
关于胸腺细胞与其他类型细胞之间的相互作用的动态，以及胸腺细胞在皮层微环境中的正选择过程中的时空分布，人们知之甚少。我们使用小鼠胸腺的双光子激光扫描显微镜来显示胸腺细胞和树突状细胞(DC)，并描述它们在皮质中的相互作用。我们发现胸腺细胞与胸腺皮质中的树突状细胞频繁接触，当胸腺细胞表达介导阳性选择的T细胞受体时，这些联系增加。我们还表明，皮质DC和趋化因子CCL21的表达与整个皮质的毛细血管密切相关。胸腺细胞中趋化因子受体CCR7的过表达导致DC-胸腺细胞相互作用的增加，而在阳性选择TCR的背景下CCR7的缺失降低了DC-胸腺细胞相互作用的程度。这些观察确定了胸腺皮质内与血管相关的微环境，该微环境促进了树突状细胞和正在接收积极选择信号的胸腺细胞之间的相互作用。免疫学杂志，2008,181：7014-7023。
Little is known about the dynamics of the interactions between thymocytes and other cell types, as well as the spatiotemporal distribution of thymocytes during positive selection in the microenvironment of the cortex. We used two-photon laser scanning microscopy of the mouse thymus to visualize thymocytes and dendritic cells (DCs) and to characterize their interactions in the cortex. We show that thymocytes make frequent contacts with DCs in the thymic cortex and that these associations increase when thymocytes express T cell receptors that mediate positive selection. We also show that cortical DCs and the chemokine CCL21 expression are closely associated with capillaries throughout the cortex. The overexpression of the chemokine receptor CCR7 in thymocytes results in an increase in DC-thymocyte interactions, while the loss of CCR7 in the background of a positive-selecting TCR reduces the extent of DC-thymocyte interactions. These observations identify a vasculature-associated microenvironment within the thymic cortex that promotes interactions between DCs and thymocytes that are receiving positive selection signals. The Journal of Immunology, 2008, 181: 7014-7023.