Evaluation of the EUROIMMUN automated chemiluminescence immunoassays for measurement of four core biomarkers for Alzheimer’s disease in cerebrospinal fluid

Introduction: , tTau, and pTau(181) in human cerebrospinal fluid (CSF). Methods: ChLIAs were validated according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI). Optimal cut-offs for biomarkers and biomarker ratios were determined using samples from 219 AD patients and 220 patients with AD-related symptoms. For performance comparison, biomarker concentrations were measured in 110 diagnostic leftover samples using the ChLIAs and established Lumipulse G assays (Fujirebio). Results: All ChLIAs met CLSI criteria. Overall agreement between assays was 89.0%-97.3 % with highly correlating results (Pearson's correlation coefficients: 0.82-0.99). Passing-Bablok regression analysis revealed systematic differences. Discussion: EUROIMMUN ChLIAs showed good analytical performances and represent new valuable tools for diagnostics of AD.