Imaging Inflammation in Alzheimer's Disease With 11C-ER176

Inflammation likely plays a role in the damage to the brain caused by Alzheimer's disease.

Accurately measuring inflammation in the brain could provide new information about the
mechanisms that cause Alzheimer's disease, and could help identify new treatments that reduce
inflammation. Positron emission tomography (PET) imaging is a type of brain scanning method
that allows investigators to measure small molecules in the brain. ER176-PET was recently
developed as an improved method for measuring brain inflammation. However, ER176-PET has not
yet been used in patients with Alzheimer's disease. The investigators propose to use
ER176-PET imaging in subjects with mild cognitive impairment (a very early stage of
Alzheimer's disease) or mild Alzheimer's disease to compare the amount of inflammation with
that seen in older control subjects. The investigators will first use a "gold standard"
method of measuring ER176 in brain that requires sampling arterial blood during the scan. The
investigators will compare these results to those obtained using novel methods that don't
require blood sampling. The investigators hope to show that ER176 is a useful tool for
measuring inflammation in Alzheimer's disease, and that the investigators can develop a way
to obtain ER176 PET scans that don't require arterial blood sampling.

This study uses a special type of scan called a PET scan to take pictures of the brain.
During the PET scan, a special dye is injected into the body. Two types of dye will be used
in this study: Florbetaben and 11C-ER176. Florbetaben sticks to amyloid plaques, which are in
the brain in Alzheimer's disease. Florbetaben has been approved by the Food and Drug
Administration to help diagnose Alzheimer's disease. 11C-ER176 sticks to parts of the brain
where there is inflammation. Past studies have shown that inflammation is present in the
brains of patients with Alzheimer's disease.

Inclusion Criteria:

1. Age 50 and older

2. Meet criteria for either a) amnestic mild cognitive impairment or Alzheimer's disease,
or b) have no cognitive impairment

3. If you are unable to provide informed consent, you must have a surrogate decision
maker and be able to verbally assent to the study procedures

4. Written and oral fluency in English

5. Able to participate in all scheduled evaluations and to complete all required tests
and procedures.

6. In the opinion of the investigator, you must be considered likely to comply with the
study protocol and to have a high probability of completing the study.

Exclusion Criteria:

1. Past or present history of certain brain disorders other than MCI or AD.

2. Certain significant medical conditions, which make study procedures of the current
study unsafe. Such serious medical conditions include uncontrolled epilepsy and
multiple serious injuries.

3. Contraindication to MRI scanning

4. Conditions precluding entry into the scanners (e.g. morbid obesity, claustrophobia,
etc.).

5. Exposure to research related radiation in the past year that, when combined with this
study, would place you above the allowable limits.

6. Participation in the last year in a clinical trial for a disease modifying drug for
AD.

7. Inability to have a catheter in your vein for the injection of radioligand.

8. Inability to have blood drawn from your veins.

9. Taking anticoagulant medication (e.g., warfarin).