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Review
. 2017 Dec;51(4):283-296.
doi: 10.1007/s13139-017-0475-8. Epub 2017 Mar 16.

Recent Progress in the Development of TSPO PET Ligands for Neuroinflammation Imaging in Neurological Diseases

Md Maqusood Alam  1 , Jihye Lee  1 , Sang-Yoon Lee  1   2
Affiliations
Review

Recent Progress in the Development of TSPO PET Ligands for Neuroinflammation Imaging in Neurological Diseases

Md Maqusood Alam et al. Nucl Med Mol Imaging. 2017 Dec.

Abstract

Neuroinflammation is heavily associated with various neurological diseases including Alzheimer's disease, Parkinson's disease, multiple sclerosis, and stroke. It is strongly characterized by the activation of microglia which can be visualized using position emission tomography (PET). Traditionally, translocator protein 18 kDa (TSPO) has been the preferred target for imaging the inflammatory progression of the microglial component. TSPO is expressed in the outer mitochondrial membrane and present in very low concentrations in the healthy human brain, but is markedly upregulated in response to brain injury and inflammation. Due to its value as a marker of microglial activation and subsequent utility for evaluating neuroinflammation in CNS disorders, several classes of TSPO radioligands have been developed and evaluated. However, the application of these second-generation TSPO radiotracers has been subject to several limiting factors, including a polymorphism that affects TSPO binding. This review focuses on recent developments in TSPO imaging, as well as current limitations and suggestions for future directions from a medical imaging perspective.

Keywords: Microglia activation; Molecular imaging; Neuroinflammation; PET radioligand; Translocator protein.

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Conflict of interest statement

Compliance with Ethical standardsMd. Maqusood Alam, Jihye Lee, and Sang-Yoon Lee declare that they have no conflict of interest. This work was supported by a grant of the Korea Health Technology R&D project through the Korea Health Industry Development Institute (KHIDI), funded by the ministry of health and welfare, Korea (HI14C1135).This work does not contain any studies with human participants or animals performed by any of the authors.

Figures

Fig. 1
Fig. 1
First and second generation TSPO PET radioligands used for human studies
Fig. 2
Fig. 2
Second and new generation TSPO tracers in various stages of development
See this image and copyright information in PMC

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