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bioRxiv · 10.1101/476937

Agreement between 18F-Florbetapir PET imaging and cerebrospinal fluid Aβ1-42, Aβ1-40, tTau and pTau measured on the LUMIPULSE G fully automated platform

Alcolea, D.·Pegueroles, J.·Munoz, L.·Camacho, V.·Lopez-Mora, D.·Fernandez-Leon, A.·Le Bastard, N.·Huyck, E.·Nadal, A.·Olmedo, V.·Montal, V.·Vilaplana, E.·Clarimon, J.·Blesa, R.·Fortea, J.·Lleo, A.
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Abstract

INTRODUCTIONThe development of fully automated immunoassay platforms has improved the technical reliability of cerebrospinal fluid (CSF) biomarkers for Alzheimers disease.\n\nMETHODSWe quantified A{beta}1-42, A{beta}1-40, tTau and pTau levels using the Lumipulse G System in 94 CSF samples from participants of the SPIN cohort with available 18F-Florbetapir imaging. Amyloid scans were assessed visually and through automated quantification. We determined the cutoffs of CSF biomarkers that optimized their agreement with 18F-Florbetapir PET and evaluated concordance between markers of the amyloid category.\n\nRESULTSA{beta}1-42, tTau and pTau (but not A{beta}1-40) and the ratios with A{beta}1-42 had good diagnostic agreement with 18F-Florbetapir PET. As a marker of amyloid pathology, the A{beta}1-42/A{beta}1-40 ratio had higher agreement and better correlation with amyloid PET than A{beta}1-42 alone.\n\nDISCUSSIONCSF biomarkers measured with the Lumipulse G System show good agreement with amyloid imaging. Combination of A{beta}1-42 with A{beta}1-40 increases the agreement between markers of amyloid pathology.

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Alcolea, D., Pegueroles, J., Munoz, L., Camacho, V., Lopez-Mora, D., Fernandez-Leon, A., Le Bastard, N., Huyck, E., Nadal, A., Olmedo, V., Montal, V., Vilaplana, E., Clarimon, J., Blesa, R., Fortea, J., Lleo, A.. 2018-11-27. Agreement between 18F-Florbetapir PET imaging and cerebrospinal fluid Aβ1-42, Aβ1-40, tTau and pTau measured on the LUMIPULSE G fully automated platform. https://doi.org/10.1101/476937

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