Molecular Imaging Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, United States.
Chemical Biology Laboratory, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, Maryland 21702, United States.
J Am Chem Soc. 2022 Jun 29;144(25):11075-11080. doi: 10.1021/jacs.2c02962. Epub 2022 Jun 13.
Photoconvertible tracking strategies assess the dynamic migration of cell populations. Here we develop hototruncation-ssisted ell racking (PACT) and apply it to evaluate the migration of immune cells into tumor-draining lymphatics. This method is enabled by a recently discovered cyanine photoconversion reaction that leads to the two-carbon truncation and consequent blue-shift of these commonly used probes. By examining substituent effects on the heptamethine cyanine chromophore, we find that introduction of a single methoxy group increases the yield of the phototruncation reaction in neutral buffer by almost 8-fold. When converted to a membrane-bound cell-tracking variant, this probe can be applied in a series of and experiments. These include quantitative, time-dependent measurements of the migration of immune cells from tumors to tumor-draining lymph nodes. Unlike previously reported cellular photoconversion approaches, this method does not require genetic engineering and uses near-infrared (NIR) wavelengths. Overall, PACT provides a straightforward approach to label cell populations with spatiotemporal control.
光转化追踪策略用于评估细胞群体的动态迁移。在这里，我们开发了光诱导截断辅助细胞追踪（PACT）技术，并将其应用于评估免疫细胞向肿瘤引流淋巴管的迁移。该方法依赖于最近发现的菁染料光转化反应，该反应导致这些常用探针的两个碳截断和随后的蓝移。通过研究取代基对七甲川菁类生色团的影响，我们发现，在中性缓冲液中，引入单个甲氧基基团几乎将光截断反应的产率提高了 8 倍。当转化为膜结合的细胞追踪变体时，该探针可用于一系列 和 实验。这些实验包括定量、时间依赖性地测量免疫细胞从肿瘤到肿瘤引流淋巴结的迁移。与之前报道的细胞光转化方法不同，该方法不需要基因工程，并且使用近红外（NIR）波长。总的来说，PACT 为具有时空控制的细胞群体标记提供了一种简单的方法。
