Elevation of {beta}-amyloid 1-42 autoantibodies in the blood of amnestic patients with mild cognitive impairment.
OBJECTIVE
To develop a blood-based test for screening populations at risk for Alzheimer disease.


METHODS
Case-control study. Subjects A total of 180 patients with mild cognitive impairment (MCI) and 105 age-matched, cognitively normal controls.


METHODS
The titer of beta-amyloid 1-42 autoantibodies in the plasma was obtained at the time of diagnosis and evaluated by enzyme-linked immunosorbent assay before and after dissociation of the antigen-antibody complexes. A total of 107 patients with MCI were followed up for 36 months; 70 of the 107 cases progressed to Alzheimer disease.


RESULTS
The average level of beta-amyloid 1-42 plasma autoantibodies in patients with MCI that progressed to Alzheimer disease, but not that of the stable cases, was significantly higher than in cognitively normal controls (P < .001).


CONCLUSIONS
The results suggest that the plasma beta-amyloid 1-42 autoantibodies parallel beta-amyloid 42 deposition in the brain, which is known to precede by several years the clinical onset of Alzheimer disease. The evaluation of beta-amyloid 1-42 autoantibodies after dissociation of the complexes is a simple and inexpensive method that can be used to predict the occurrence of Alzheimer disease.
Storace
Daniela
D
Department of Internal Medicine and Medical Specialties, University of Genoa, Italy.
Cammarata
Sergio
S
Borghi
Roberta
R
Sanguineti
Roberta
R
Giliberto
Luca
L
Piccini
Alessandra
A
Pollero
Valeria
V
Novello
Cristina
C
Caltagirone
Carlo
C
Smith
Mark A
MA
Bossù
Paola
P
Perry
George
G
Odetti
Patrizio
P
Tabaton
Massimo
M
D000647:Amnesia / Q000097:blood / Q000150:complications; D016229:Amyloid beta-Peptides / Q000276:immunology*; D053327:Apolipoprotein E4 / Q000235:genetics; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000097:blood* / Q000209:etiology / Q000235:genetics / Q000276:immunology*; D005500:Follow-Up Studies; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood*; D010446:Peptide Fragments / Q000276:immunology*; D011336:Probability
D016229:Amyloid beta-Peptides; D053327:Apolipoprotein E4; D007074:Immunoglobulin G; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42)