Biomarkers.

Area of Science:

• Neurology
• Biomarker Discovery
• Diagnostic Assays

Background:

• Glial fibrillary acidic protein (GFAP) is a recognized biomarker for neurological disorders.
• The Lumipulse G GFAP plasma assay is a commercially available diagnostic tool.
• This study evaluates the GFAP assay's performance in cerebrospinal fluid (CSF) samples.

Purpose of the Study:

• To assess the clinical performance of the Lumipulse G GFAP assay in CSF.
• To determine if GFAP levels can differentiate Alzheimer's disease (AD) from other cognitive conditions.
• To evaluate GFAP as a potential biomarker alongside established AD markers.

Main Methods:

• Utilized the fully automated Lumipulse system (CLEIA platform).
• Assessed 30 CSF samples (10 each from AD, MCI, and cognitively unimpaired individuals).
• Simultaneously measured GFAP, β-amyloid (Aβ40, Aβ42), and pTau181 levels.

Main Results:

• The GFAP assay significantly differentiated amyloid accumulation groups (p < 0.05).
• GFAP showed a moderate correlation with pTau181 (r = 0.588).
• Receiver operating characteristic (ROC) analysis yielded an area under the curve (AUC) of 0.72 for distinguishing amyloid-positive subjects.

Conclusions:

• The Lumipulse G GFAP assay in CSF shows potential for differentiating AD from non-AD cases.
• GFAP may serve as a valuable biomarker for AD, complementing Aβ40, Aβ42, and pTau181.
• Further research is needed to investigate GFAP elevation in other neurological disorders.