Research Center for Radioisotope, Radiopharmaceutical, and Biodosimetry Technology, Research Organization for Nuclear Energy, National Research and Innovation Agency, Puspiptek, Banten, 15314, Indonesia.
Anal Biochem. 2022 Oct 15;655:114854. doi: 10.1016/j.ab.2022.114854. Epub 2022 Aug 11.
The translocator protein 18 kDa (TSPO) was first identified in 1997, and has now become one of the appealing subcellular targets in medicinal chemistry and its related fields. TSPO involves in a variety of diseases, covering neurodegenerative diseases, psychiatric disorders, cancers, and so on. To date, various high-affinity TSPO ligands labelled with single-photon emission computed tomography (SPECT)/positron emission tomography (PET) radionuclides have been reported, with some third-generation radioligands advanced to clinical trials. On the other hand, only a few number of TSPO ligands have been labelled with fluorophores for disease diagnosis. It is noteworthy that the majority of the TSPO fluorescent probes synthesised to date are based on visible fluorophores, suggesting that their applications are limited to in vitro studies, such as in vitro imaging of cancer cells, post-mortem analysis, and tissue biopsies examinations. In this context, the potential application of TSPO ligands can be broadened for in vivo investigations of human diseases by labelling with near-infrared (NIR)-fluorophores or substituting visible fluorophores with NIR-fluorophores on the currently developed fluorescent probes. In this review article, recent progress on fluorescent probes targeting the TSPO are summarised, with an emphasis on development trend in recent years and application prospects in the future.
转位蛋白 18kDa（TSPO）于 1997 年首次被鉴定出来，现已成为医学化学及其相关领域中具有吸引力的亚细胞靶标之一。TSPO 涉及多种疾病，涵盖神经退行性疾病、精神疾病、癌症等。迄今为止，已经报道了各种与单光子发射计算机断层扫描（SPECT）/正电子发射断层扫描（PET）放射性核素标记的高亲和力 TSPO 配体，其中一些第三代放射性配体已进入临床试验。另一方面，只有少数 TSPO 配体被荧光团标记用于疾病诊断。值得注意的是，迄今为止合成的大多数 TSPO 荧光探针都是基于可见荧光团，这表明它们的应用仅限于体外研究，例如癌细胞的体外成像、死后分析和组织活检检查。在这种情况下，通过用近红外（NIR）荧光团标记或用 NIR 荧光团替代现有荧光探针上的可见荧光团，可以拓宽 TSPO 配体在人类疾病的体内研究中的应用。本文总结了近年来针对 TSPO 的荧光探针的最新进展，重点介绍了近年来的发展趋势和未来的应用前景。
