Macrophages are crucial innate immune system cells that have the ability to generate large amounts of HO in the cytoplasm to combat germs. Macrophage mitochondria also produce HO to participate in the antimicrobial response when infected by bacteria. However, visualization of HO production in the mitochondria of bacterially infected macrophages is extremely challenging due to the lack of appropriate research methods. Here, by developing a new mitochondrial-targeting fluorescent HO probe, combined with confocal fluorescence imaging, we report for the first time that HO production in the mitochondria of bacterially infected macrophages (Raw264.7 cells) was visualized with a fluorescent probe. In addition, the developed probe has accurate mitochondrial targeting ability, large Stokes shift, fast response capability, high selectivity and sensitivity (detection limit of 4.346 × 10 M), and the probe can be used to detect HO in living cells and zebrafish. Therefore, this work is expected to be used to further reveal the biological function of HO in subcellular mitochondria.

中文翻译：

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大Stokes位移线粒体靶向H2O2荧光探针的构建及其在细菌感染中的应用

巨噬细胞是重要的先天免疫系统细胞，能够在细胞质中产生大量 H2O 来对抗细菌。当巨噬细胞线粒体被细菌感染时，也会产生 H2O2 参与抗菌反应。然而，由于缺乏适当的研究方法，细菌感染巨噬细胞线粒体中 H2O 产生的可视化极具挑战性。在这里，通过开发一种新的线粒体靶向荧光 H2O2 探针，结合共聚焦荧光成像，我们首次报告用荧光探针可视化细菌感染的巨噬细胞（Raw264.7 细胞）线粒体中 H2O2 的产生。此外，所开发的探针具有精确的线粒体靶向能力、斯托克斯位移大、响应速度快、选择性和灵敏度高（检测限为4.346×10 M），可用于活细胞和斑马鱼中H2O的检测。因此，这项工作有望进一步揭示H2O在亚细胞线粒体中的生物学功能。