Laboratory of Organic Chemistry, ETH Zürich, 8093, Zürich, Switzerland.
Institute of Pharmaceutical Sciences, ETH Zürich, 8093, Zürich, Switzerland.
ACS Chem Biol. 2020 Jun 19;15(6):1613-1620. doi: 10.1021/acschembio.0c00208. Epub 2020 Apr 28.
Cell trackers are fluorescent chemical tools that facilitate imaging and tracking cells within live organisms. Despite their versatility, these dyes lack specificity, tend to leak outside of the cell, and stain neighboring cells. Here, we report a dual-activatable cell tracker for increased spatial and temporal staining control, especially for single-cell tracking. This probe overcomes the typical problems of current cell trackers: off-target staining, high background signal, and leakage from the intracellular medium. Staining with this dye is not cytotoxic, and it can be used in sensitive primary cells. Moreover, this dye is resistant to harsh fixation and permeabilization conditions and allows for multiwavelength studies with confocal microscopy and fluorescence-activated cell sorting. Using this cell tracker, we performed homing experiments in mice with primary splenocytes and tracked a single cell in a heterogeneous, multicellular culture environment for over 20 h. These experiments, in addition to comparative proliferation studies with other cell trackers, demonstrated that the signal from this dye is retained in cells for over 72 h after photoactivation. We envision that this type of probes will facilitate the analysis of single-cell behavior and migration in cell culture and experiments.
细胞示踪剂是一种荧光化学工具，可用于在活体生物中对细胞进行成像和跟踪。尽管它们用途广泛，但这些染料缺乏特异性，往往会从细胞内漏出，并对邻近细胞进行染色。在这里，我们报告了一种双激活型细胞示踪剂，以增强空间和时间染色控制，特别是用于单细胞跟踪。该探针克服了当前细胞示踪剂的典型问题：非靶向染色、高背景信号和细胞内介质泄漏。用这种染料染色不会产生细胞毒性，并且可以用于敏感的原代细胞。此外，该染料耐苛刻的固定和通透化条件，允许使用共聚焦显微镜和荧光激活细胞分选进行多波长研究。使用这种细胞示踪剂，我们在小鼠的原代脾细胞中进行了归巢实验，并在超过 20 小时的时间内跟踪了一个异质多细胞培养环境中的单个细胞。除了与其他细胞示踪剂进行的比较增殖研究外，这些实验表明，这种染料的信号在光激活后超过 72 小时仍保留在细胞内。我们设想这种类型的探针将有助于在细胞培养和实验中分析单细胞行为和迁移。
