Nucl Med Mol Imaging.  2017 Dec;51(4):283-296. 10.1007/s13139-017-0475-8.

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

• Alam MM
• Lee J
• Lee SY

• KMID: 2403501
• DOI: http://doi.org/10.1007/s13139-017-0475-8

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.

Keyword

Microglia activation; Molecular imaging; Neuroinflammation; PET radioligand; Translocator protein

MeSH Terms

Alzheimer Disease
Brain
Brain Injuries
Diagnostic Imaging
Humans
Inflammation
Ligands*
Microglia
Mitochondrial Membranes
Molecular Imaging
Multiple Sclerosis
Parkinson Disease
Stroke
Ligands