AD-associated Protein Research Articles

The indusium griseum in Alzheimer's disease: an immunocytochemical study

The immunocytochemical features of the indusium griseum (IG) were compared with the corresponding hippocampus in 5 patients with Alzheimer's disease (AD) and 5 age-matched nondemented individuals using antibodies against β-amyloid, the A68 protein (Alz-50 antibody), tau, ubiquitin and synapsin I. β-Amyloid-positive plaques were prominent in the AD hippocampus but were not present in the IG. Numerous Alz-50, tau and ubiquitin-positive neurofibrillary tangles and dystrophic neurites were observed in the AD hippocampus but were infrequent in the IG. Synapsin I immunoreactivity was significantly reduced in both the AD hippocampus and the AD IG when compared to age-matched patients. These findings suggest that the IG may be resistant to factors that trigger production of abnormal AD-associated proteins. Loss of synaptic input alone may not account for the AD-associated changes in the hippocampus since synaptic depletion was seen in both the hippocampus and the unaffected AD IG.

Alterations in Alzheimer's Disease—Associated Protein in Alzheimer's Disease Frontal and Temporal Cortex

Alzheimer's disease (AD)-associated protein is present in brain and cerebrospinal fluid of patients with AD but not in adult, nondemented, normal controls. This protein may represent an abnormal epitope of the "tau" microtubule-associated protein and has been detected before the appearance of senile plaques and neurofibrillary tangles. The amount of AD-associated protein in the frontal and temporal cortices in 93 cases of neuropathologically confirmed AD was compared with the amount that was present in 20 cases without AD. The amount of AD-associated protein was significantly increased in the cases of AD for both brain regions compared with that in the cases without AD. The presence of high levels of this protein is a useful adjunct, postmortem marker of the presence of AD and may eventually lead to tests that allow early detection of individuals at risk for this disease.