title: High Content, Multi-Parameter Analyses in Buccal Cells to Identify Alzheimer's Disease.
abstract: Alzheimer's disease (AD) is a degenerative brain disorder and is the most common form of dementia. Minimally invasive approaches are required that combine biomarkers to identify individuals who are at risk of developing mild cognitive impairment (MCI) and AD, to appropriately target clinical trials for therapeutic discovery as well as lifestyle strategies aimed at prevention. Buccal mucosa cells from the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Ageing cohort (n=60) were investigated for cytological markers that could be used to identify both MCI and AD individuals. Visual scoring of the buccal cytome demonstrated a significantly lower frequency of basal and karyorrhectic cells in the MCI group compared with controls. A high content, automated assay was developed using laser scanning cytometry to simultaneously measure cell types, nuclear DNA content and aneuploidy, neutral lipid content, putative Tau and amyloid-β (Aβ) in buccal cells. DNA content, aneuploidy, neutral lipids and Tau were similar in all groups. However, there was significantly lower Tau protein in both basal and karyolytic buccal cell types compared with differentiated buccal cells. Aβ, as measured by frequency of cells containing Aβ signal, as well as area and integral of Aβ signal, was significantly higher in the AD group compared with the control group. Buccal cell Aβ was correlated with mini-mental state examination (MMSE) scores (r = -0.436, P=0.001) and several blood-based biomarkers. Combining newly identified biomarkers from buccal cells with those already established may offer a potential route for more specific biomarker panels which may substantially increase the likelihood of better predictive markers for earlier diagnosis of AD.
authors.forename: Maxime
authors.initials: M
authors.lastname: François
authors.forename: Michael F
authors.initials: MF
authors.lastname: Fenech
authors.forename: Philip
authors.initials: P
authors.lastname: Thomas
authors.forename: Maryam
authors.initials: M
authors.lastname: Hor
authors.forename: Alan
authors.initials: A
authors.lastname: Rembach
authors.forename: Ralph N
authors.initials: RN
authors.lastname: Martins
authors.forename: Stephanie R
authors.initials: SR
authors.lastname: Rainey-Smith
authors.forename: Colin L
authors.initials: CL
authors.lastname: Masters
authors.forename: David
authors.initials: D
authors.lastname: Ames
authors.forename: Christopher C
authors.initials: CC
authors.lastname: Rowe
authors.forename: S Lance
authors.initials: SL
authors.lastname: Macaulay
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Hill
authors.affiliation: CSIRO Food and Nutrition Flagship, Genome Health and Personalised Nutrition, Gate 13, Kintore Ave, Adelaide, South Australia, 5000, Australia. wayne.leifert@csiro.au.
authors.forename: Wayne R
authors.initials: WR
authors.lastname: Leifert
authors.lastname: The Australian Imaging Biomarkers And Lifestyle Study Research Group
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis*; D016229:Amyloid beta-Peptides / Q000378:metabolism; D000704:Analysis of Variance; D001391:Azo Compounds / Q000378:metabolism; D001798:Blood Proteins / Q000378:metabolism; D060825:Cognitive Dysfunction / Q000473:pathology; D015331:Cohort Studies; D004247:DNA / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D047569:Laser Scanning Cytometry; D008297:Male; D008609:Mental Status Schedule; D009061:Mouth Mucosa / Q000378:metabolism* / Q000473:pathology*; D010446:Peptide Fragments / Q000378:metabolism; D016875:tau Proteins / Q000378:metabolism
chemical_list: D016229:Amyloid beta-Peptides; D001391:Azo Compounds; D001798:Blood Proteins; D010446:Peptide Fragments; C075222:amyloid beta-protein (1-42); D016875:tau Proteins; D004247:DNA; C011049:oil red O