Interleukin 1 Type 1 Receptor Restore: A Genetic Mouse Model for Studying Interleukin 1 Receptor-Mediated Effects in Specific Cell Types
Interleukin 1 Type 1 Receptor Restore: A Genetic Mouse Model for Studying Interleukin 1 Receptor-Mediated Effects in Specific Cell Types
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DOI：
10.1523/jneurosci.3199-14.2015
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发表时间：
2015-02-18
影响因子：
5.3
通讯作者：
Quan, Ning
中科院分区：
文献类型：
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作者：
Liu, Xiaoyu;Yamashita, Tetsuji;Quan, Ning
白细胞介素-1（IL-1）通过I型IL-1受体（IL-1 R1）介导CNS中多种神经生理学和神经病理学效应。然而，IL-1 R1表达细胞类型和IL-1 R1的细胞类型特异性功能的鉴定仍然具有挑战性。在这项研究中，我们创建了一个新的遗传小鼠模型，其中IL-1 R1基因表达被破坏的内含子插入loxP侧翼的破坏性序列，可以删除Cre重组酶，导致恢复IL-1 R1基因表达的内源性启动子。在IL-1 R1基因的终止密码子处引入第二突变，以允许通过3 HA标签追踪恢复的IL-1 R1蛋白，并通过td Tomato荧光追踪IL-1 R1 mRNA。这些动物被命名为IL-1 R1（r/r），并表现出IL-1 R1敲除表型。我们使用IL-1 R1全面恢复的小鼠（IL-1 R1（GR/GR））作为IL-1 R1报告基因，并观察到脑内皮细胞中IL-1 R1 mRNA和蛋白的一致标记。产生了两种细胞类型特异性IL-1 R1恢复系：Tie 2Cre-IL-1 R1（r/r）和LysMCre-IL-1 R1（r/r）。在IL-1 R1（r/r）或LysMCre-IL-1 R1（r/r）小鼠中未观察到脑室内注射IL-1 β诱导的脑内皮考克斯-2表达、CNS白细胞浸润和整体小胶质细胞活化，但在Tie 2Cre-IL-1 R1（r/r）小鼠中恢复。这些结果表明，内皮细胞中单独的IL-1 R1表达足以介导这些中枢IL-1诱导的应答。此外，离体IL-1 β刺激增加了野生型、Tie 2Cre-IL-1 R1（r/r）和LysMCre-IL-1 R1（r/r）小鼠骨髓细胞中IL-1 β的表达，但不增加IL-1 R1（r/r）小鼠的表达。这些结果表明该IL-1 R1恢复模型是研究IL-1 R1的细胞类型特异性功能的有价值的工具。
Interleukin-1 (IL-1) mediates diverse neurophysiological and neuropathological effects in the CNS through type I IL-1 receptor (IL-1R1). However, identification of IL-1R1-expressing cell types and cell-type-specific functions of IL-1R1 remains challenging. In this study, we created a novel genetic mouse model in which IL-1R1 gene expression is disrupted by an intronic insertion of a loxP flanked disruptive sequence that can be deleted by Cre recombinase, resulting in restored IL-1R1 gene expression under its endogenous promoters. A second mutation was introduced at stop codon of the IL-1R1 gene to allow tracking of the restored IL-1R1 protein by a 3HAtag and IL-1R1 mRNA by td Tomato fluorescence. These animals were designated as IL-1R1(r/r) and exhibited an IL-1R1 knock-out phenotype. We used IL-1R1 globally restored mice (IL-1R1(GR/GR)) as an IL-1R1 reporter and observed concordant labeling of IL-1R1 mRNA and protein in brain endothelial cells. Two cell-type-specific IL-1R1 restore lines were generated: Tie2Cre-IL-1R1(r/r) and LysMCre-IL-1R1(r/r). Brain endothelial COX-2 expression, CNS leukocyte infiltration, and global microglia activation induced by intracerebroventricular injection of IL-1 beta were not observed in IL-1R1(r/r) or LysMCre-IL-1R1(r/r) mice, but were restored in Tie2Cre-IL-1R1(r/r) mice. These results reveal IL-1R1 expression in endothelial cells alone is sufficient to mediate these central IL-1-induced responses. In addition, ex vivo IL-1 beta stimulation increased IL-1 beta expression in bone marrow cells in wild-type, Tie2Cre-IL-1R1(r/r), and LysMCre-IL-1R1(r/r), but not IL-1R1(r/r) mice. These results demonstrate this IL-1R1 restore model is a valuable tool for studying cell-type-specific functions of IL-1R1.