2005 Investigator-Initiated Research Grant

In Alzheimer’s disease, tiny protein fragments called beta-amyloid clump together, or aggregate, eventually forming deposits called amyloid plaques. Beta-amyloid is believed to be key toxic factor in disease processes. Two large fields of Alzheimer research are the (1) development of drugs that inhibit amyloid production or enhance amyloid clearance and (2) the development of brain imaging strategies that enable researchers to “see” amyloid plaques.

An effective imaging strategy may, in fact, be critical in the drug development process, because investigators would could directly measure the effect of an anti-amyloid drug.

John Seibyl, M.D., and colleagues are testing an engineered compound called 123-I IMPY that (1) attaches itself to beta-amyloid, (2) carries a safe radioactive “flag” that can be detected by positron emission tomography (PET) or single photon emission computed tomography (SPECT), (3) can travel to the brain via the bloodstream and (4) can be cleared from the brain.

The key focus of this study will be to examine the amyloid-imaging potential of 123-I IMPY by comparing scans from 14 individuals with Alzheimer’s disease and seven adults with no cognitive impairment.

The outcome of this work has implications for future studies in diagnostic and disease-monitoring procedures, as well as drug development.