Inducible transgenes under the control of the hCD68 promoter identifies mouse macrophages with a distribution that differs from the F4/80-and CSF-1R-expressing populations
Inducible transgenes under the control of the hCD68 promoter identifies mouse macrophages with a distribution that differs from the F4/80-and CSF-1R-expressing populations
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DOI：
10.1016/j.exphem.2009.09.003
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发表时间：
2009-12-01
影响因子：
2.6
通讯作者：
Torok-Storb, Beverly
中科院分区：
文献类型：
--
作者：
Pillai, Manoj M.;Hayes, Brian;Torok-Storb, Beverly
目标。巨噬细胞是成年期不同微环境的重要组成部分，在胚胎发育过程中也是如此。它们在发育中的作用排除了使用基因靶向和敲除方法来研究它们的功能。因此，我们建议创造一种巨噬细胞特异性诱导的转基因小鼠，在这种转基因小鼠中，基因可以随意打开或关闭。材料和方法。建立了在hCD68启动子下表达反向四环素激活剂(RTTA-M2)以诱导巨噬细胞特异性基因的转基因小鼠，并与其中绿色荧光蛋白(GFP)基因受四环素反应元件启动子控制的转基因报告小鼠进行杂交。双转基因动物CD68-RTTA-tet-GFP经多西环素诱导后，通过多色流式细胞仪检测血液、骨髓和脾细胞的表达，并在不同组织的新鲜冰冻切片中检测到GFP的表达。在骨髓中，可诱导的GFP表达并不局限于或包括所有表达经典巨噬细胞标志物的细胞，如F4/80。然而，在硫代乙醇酸诱导的巨噬细胞中，表达GFP的细胞对F4/80和单核巨噬细胞特异性2抗原也呈阳性。有趣的是，流动分析也表明F4/80和CSF-1R阳性人群之间几乎没有重叠。已知含有巨噬细胞的新鲜冰冻组织样本显示，表达GFP的细胞具有不同的形态。我们的结果表明，hCD68启动子在巨噬细胞群体中指导基因表达，与经典的单核-巨噬细胞标志物或启动子所定义的不同。这一群体是否在功能上是不同的仍有待确定。(C)2009年ISEH--血液学和干细胞学会。由爱思唯尔公司出版。
Objective. Macrophages are critical components of diverse microenvironments (ME) in adulthood, as well as during embryogenesis. Their role in development precludes the use of gene-targeting and knockout approaches for studying their function. Hence, we proposed to create a macrophage-specific inducible transgenic mouse where genes can be turned on or off at will.Materials and Methods. A transgenic mouse in which the reverse tetracycline activator (rtTA-M2) is expressed under the hCD68 promoter for macrophage-specific gene induction was developed and crossed with a second transgenic reporter mouse strain in which the gene for green fluorescent protein (GFP) is under the control of tetracycline responsive element promoter. After doxycycline induction of the double transgenic animals (designated CD68-rtTA-tet-GFP), inducible expression of GFP was characterized by multicolor flow cytometric analysis of blood, marrow, and spleen cells and by demonstration of GFP expression in fresh-frozen sections in diverse tissues.Results. In bone marrow, inducible GFP expression was not confined to, or inclusive of, all cells expressing the classical macrophage markers, such as F4/80. However, GFP-expressing cells in thioglycollate-elicited peritoneal macrophages were also positive for F4/80 and monocyte-macrophage-specific 2 antigen. Interestingly, flow analysis also indicated little overlap between the F4/80 and CSF-1R-positive populations. Fresh-frozen samples of tissues known to contain macrophages revealed GFP-expressing cells with variable morphologies.Conclusion. Our results show that the hCD68 promoter directs gene expression in a macrophage population distinct from that defined by classical monocyte-macrophage markers or promoters. Whether this population is functionally distinct remains to be established. (C) 2009 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc.