Pittsburgh Compound-B (PiB) binds amyloid ?-protein protofibrils.

ABSTRACT: The neuropathology of Alzheimer's disease (AD) includes amyloid plaque formation by the amyloid ?-protein (A?) and intracellular paired helical filament formation by tau protein. These neuropathogenetic features correlate with disease progression and have been revealed in brains of AD patients using positron emission tomography (PET). One of the most useful positron emission tomography imaging agents has been Pittsburgh Compound-B (PiB). However, since its introduction in 2002, substantial evidence has accumulated suggesting that A? oligomerization and protofibril formation, rather than fibril formation per se, may be the more important pathogenetic event in AD. Detecting protofibrils and oligomeric forms of A? thus may be of value. We report here the results of experiments to determine whether PiB binds to oligomers or protofibrils formed by A?40 and A?42. We observed strong binding to A?42 fibrils, significant binding to protofibrils, and weaker binding to A?42 oligomers. PiB also binds A?40 fibrils, but its binding to A?40 protofibrils and oligomers is substantially lower than for that observed for A?42.

SUBMITTER: Yamin G 

PROVIDER: S-EPMC5225051 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature