Dementia Japan 28:211-219, 2014

In vivo imaging of neuroinflammation in Alzheimer's disease

Makoto Higuchi, Bin Ji, Jun Maeda, Anna Barron, Tetsuya Suhara

Molecular Imaging Center, National Institute of Radiological Sciences

    Immunocompetent cells in the brain as exemplified by microglia are crucially involved in the homeostasis of local environment by protection of neurons against toxic stimuli, while they also exert neurotoxicity in pathological conditions.  Translocator protein (TSPO) is a mitochondrial component functioning in the neurosteroidogenesis, and has attracted research interests as its upregulation in deleterious microglia can be visualized in living brains with positron emission tomography (PET) and specific radioligands.  Although TSPO ligands currently available for PET imaging are of limited utility in diagnostic and therapeutic assessments of Alzheimer's disease (AD) patients, preclinical PET assays of animals modeling AD can facilitate development of new imaging agents with high sensitivity and selectivity for microglial TSPO.  In vivo imaging of other inflammatory elements such as cyclooxygenases would also help to monitor multifunctionality of microglia and associated cells in combination with TSPO-PET.

Address correspondence to Dr. Makoto Higuchi, Molecular Imaging Center, National Institute of Radiological Sciences (4-9-1 Anagawa, Inage-ku, Chiba, Chiba 263-8555, Japan)