title: Evolution of Abeta42 and Abeta40 levels and Abeta42/Abeta40 ratio in plasma during progression of Alzheimer's disease: a multicenter assessment.
abstract: OBJECTIVE
  To better understand the seemingly contradictory plasma beta-amyloid (Abeta) results in Alzheimer's disease (AD) patients by using a newly developed plasma Abeta assay, the INNO-BIA plasma Abeta forms, in a multicenter study.
  
  
  METHODS
  A combined retrospective analysis of plasma Abeta isoforms on mild cognitive impairment (MCI) from three large cross-sectional studies involving 643 samples from the participating German and Swedish centers.
  
  
  RESULTS
  Detection modules based on two different amino (N)-terminal specific Abeta monoclonal antibodies demonstrated that Abeta in plasma could be reliable quantified using a sandwich immunoassay technology with high precision, even for low Abeta42 plasma concentrations. Abeta40 and Abeta42 concentrations varied consistently with the ApoE genotype, while the Abeta42/Abeta40 ratio did not. Irrespective of the decrease of the Abeta42/Abeta40 ratio with age and MMSE, this parameter was strongly associated with AD, as defined in this study by elevated hyperphosphorylated (P-tau181P) levels in cerebrospinal fluid (CSF).
  
  
  CONCLUSIONS
  A highly robust assay for repeatedly measuring Abeta forms in plasma such as INNO-BIA plasma Abeta forms might be a useful tool in a future risk assessment of AD.
authors.affiliation: Sahlgrenska University Hospital, Göteborg University, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Blennow
authors.forename: G
authors.initials: G
authors.lastname: De Meyer
authors.forename: O
authors.initials: O
authors.lastname: Hansson
authors.forename: L
authors.initials: L
authors.lastname: Minthon
authors.forename: A
authors.initials: A
authors.lastname: Wallin
authors.forename: H
authors.initials: H
authors.lastname: Zetterberg
authors.forename: P
authors.initials: P
authors.lastname: Lewczuk
authors.forename: H
authors.initials: H
authors.lastname: Vanderstichele
authors.forename: E
authors.initials: E
authors.lastname: Vanmechelen
authors.forename: J
authors.initials: J
authors.lastname: Kornhuber
authors.forename: J
authors.initials: J
authors.lastname: Wiltfang
authors.forename: I
authors.initials: I
authors.lastname: Heuser
authors.forename: W
authors.initials: W
authors.lastname: Maier
authors.forename: C
authors.initials: C
authors.lastname: Luckhaus
authors.forename: E
authors.initials: E
authors.lastname: Rüther
authors.forename: M
authors.initials: M
authors.lastname: Hüll
authors.forename: H
authors.initials: H
authors.lastname: Jahn
authors.forename: H J
authors.initials: HJ
authors.lastname: Gertz
authors.forename: L
authors.initials: L
authors.lastname: Frölich
authors.forename: H
authors.initials: H
authors.lastname: Hampel
authors.forename: R
authors.initials: R
authors.lastname: Pernetzki
mesh_terms: D000368:Aged; D000375:Aging; D000544:Alzheimer Disease / Q000097:blood* / Q000175:diagnosis*; D016229:Amyloid beta-Peptides / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D005858:Germany; D006801:Humans; D007118:Immunoassay / Q000379:methods; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010446:Peptide Fragments / Q000097:blood*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D013548:Sweden
chemical_list: D016229:Amyloid beta-Peptides; D015415:Biomarkers; D010446:Peptide Fragments; C078592:amyloid beta-protein (1-40); C075222:amyloid beta-protein (1-42)