The roles of IL-7 and IL-15 in niches for lymphocyte progenitors and immune cells in lymphoid organs
The roles of IL-7 and IL-15 in niches for lymphocyte progenitors and immune cells in lymphoid organs
复制标题
IL-7和IL-15在淋巴器官淋巴细胞祖细胞和免疫细胞微环境中的作用
DOI：
10.1007/978-3-030-86016-5_4
复制
发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Cui G
中科院分区：
文献类型：
--
作者：
Ikuta K;Hara T;Abe S;Asahi T;Takami D;Cui G
淋巴器官由免疫细胞和基质细胞组成。基质细胞产生各种细胞因子，支持免疫细胞的发育、维持和反应。IL-7和IL-15是基质细胞产生的主要细胞因子，对淋巴细胞和先天淋巴样细胞（ILCs）的发育和维持至关重要。此外，IL-7在淋巴器官的器官发生中是不可缺少的。然而，由于这两种细胞因子的含量相对较低，直接检测它们的表达一直很困难。最近，一些研究小组成功建立了IL-7和IL-15报告小鼠系。如预期的那样，IL-7和IL-15在骨髓和淋巴结的间充质间质细胞以及胸腺上皮细胞中检测到。此外，IL-7和IL-15分别在淋巴内皮细胞和血液内皮细胞中表达差异。除了IL-7和IL-15的表达外，许多研究小组还利用细胞类型特异性敲除小鼠分析了IL-7和IL-15的局部功能。从这些实验中，表达cxcl12的间充质基质细胞被确定为早期B细胞前体的主要生态位。单细胞RNA测序（scRNA-seq）分析揭示了淋巴器官中基质细胞的不同亚群，包括那些同时表达IL-7和IL-15的细胞。未来的研究仍需要阐明哪些基质细胞作为骨髓中ILCs和NK细胞早期前体的生态位。
Lymphoid organs consist of immune cells and stromal cells. The stromal cells produce various cytokines that support the development, maintenance, and response of the immune cells. IL-7 and IL-15 are the major cytokines produced by stromal cells and are essential for the development and maintenance of lymphocytes and innate lymphoid cells (ILCs). In addition, IL-7 is indispensable for the organogenesis of lymphoid organs. However, because the amount of these two cytokines is relatively low, it has been difficult to directly detect their expression. Recently, several groups succeeded in establishing IL-7 and IL-15 reporter mouse lines. As expected, IL-7 and IL-15 were detected in mesenchymal stromal cells in the bone marrow and lymph nodes and in epithelial cells in the thymus. Furthermore, IL-7 and IL-15 were differentially expressed in lymphatic endothelial cells and blood endothelial cells, respectively. In addition to their expression, many groups have analyzed the local functions of IL-7 and IL-15 by using cell-type-specific knockout mice. From these experiments, CXCL12-expressing mesenchymal stromal cells were identified as the major niche for early B cell precursors. Single-cell RNA sequencing (scRNA-seq) analysis has revealed different subpopulations of stromal cells in the lymphoid organs, including those that express both IL-7 and IL-15. Future research is still needed to elucidate which stromal cells serve as the niche for the early precursors of ILCs and NK cells in the bone marrow.