Radioligand development for PET imaging of beta-amyloid (Abeta)--current status.
Two of the main pathological hallmarks of Alzheimer's disease (AD) are neuritic plaques and neurofibrillary tangles. Significant evidence supports a critical and probable causative role of beta amyloid (Abeta) plaque formation. Since neuroprotective treatments are typically most effective at early stages of injury, the detection and measurement of Abeta load in living brain should be performed at early and perhaps even presymptomatic stages of AD. Two primary targets of molecular imaging research with positron emission tomography (PET) are to develop surrogate markers (radioligands) for assessing disease progression and for monitoring the efficacy of developmental therapeutics. Here, we review the current status of radioligand development for PET imaging of Abeta aggregates. General structure-activity relationships have emerged, including the identification of at least three different ligand binding sites in various Abeta aggregates and recognition of the general structural requirements for ligand binding at each site. Also a few radioligands applicable to imaging Abeta plaques in living human brain with positron emission tomography (PET) have emerged, including [(11)C]PIB, [(11)C]SB-13 and [(18)F]FDDNP.
Cai
Lisheng
L
Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892, USA. cail@intra.nimh.nih.gov.
Innis
Robert B
RB
Pike
Victor W
VW
D016229:Amyloid beta-Peptides / Q000378:metabolism*; D001665:Binding Sites; D049268:Positron-Emission Tomography; D011869:Radioligand Assay; D013329:Structure-Activity Relationship
D016229:Amyloid beta-Peptides