The validity of 18F-GE180 as a TSPO imaging agent
- 84 Downloads
To image the 18-kDa mitochondrial translocator protein (TSPO), a putative biomarker for inflammation, dozens of PET radioligands have been synthesized over the years . None of them, however, presents optimal imaging characteristics. A drawback common to most, if not all, TSPO ligands is that they are sensitive to a single-aminoacid polymorphism of the target protein . This polymorphism differentiates subjects into high- (HAB), mixed- (MAB), and low- (LAB) affinity binders.
Therefore, a TSPO ligand providing better imaging quality is still a much sought-after goal. 18F-GE180 is a novel tricyclic indole compound that binds to TSPO with high affinity , and has been used with satisfactory results in a variety of preclinical models [4, 5, 6]. Head-to-head comparisons in animal models of neuroinflammation showed 18F-GE180 to have better imaging properties than 11C-(R)-PK11195  and 18F-DPA-714 , although it seemed to be less sensitive than 11C-DPA-713 .
Compliance with ethical standards
Conflict of interest
The authors declare they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
- 5.Chaney A, Cropper HC, Johnson EM, et al. (11)C-DPA-713 versus (18)F-GE-180: a preclinical comparison of TSPO-PET tracers to visualize acute and chronic neuroinflammation in a mouse model of ischemic stroke. J Nucl Med. 2018;60(1):122–28.Google Scholar
- 10.Albert NL, Unterrainer M, Fleischmann DF, et al. TSPO PET for glioma imaging using the novel ligand 18F-GE-180: first results in patients with glioblastoma. Eur J Nucl Med Mol Imaging. 2017;44(13):2230–238.Google Scholar
- 11.Unterrainer M, Fleischmann DF, Diekmann C, et al. Comparison of (18)F-GE-180 and dynamic (18)F-FET PET in high grade glioma: a double-tracer pilot study. Eur J Nucl Med Mol Imaging. 2018 Sep 22 [Epub ahead of print].Google Scholar
- 16.Kreisl WC, Fujita M, Fujimura Y, et al. Comparison of [(11)C]-(R)-PK 11195 and [(11)C]PBR28, two radioligands for translocator protein (18 kDa) in human and monkey: implications for positron emission tomographic imaging of this inflammation biomarker. NeuroImage. 2010;49:2924–32.CrossRefGoogle Scholar