A First-In-Class Antibody Enabling Detection of Altered Peripheral Non-Phosphorylated Clusterin With Translational...

Area of Science:

• Neuroscience
• Biochemistry
• Immunology

Background:

• Clinical dementia diagnosis, including Alzheimer's disease (AD), is subjective, relying on memory tests and caregiver reports.
• Reliable biomarkers are needed for objective diagnosis, but clusterin (CLU), an AD risk gene product, shows high variability in patients.
• CLU in blood can be phosphorylated, but these modifications differ from brain CLU, suggesting peripheral origins.

Purpose of the Study:

• To develop a tool for modification-specific CLU detection in blood.
• To investigate the potential of non-phosphorylated CLU as a biomarker for dementia.
• To explore the role of peripheral phosphorylated CLU in disease pathogenesis.

Main Methods:

• Generation of a monoclonal antibody (3D3F10) targeting non-phosphorylated CLU.
• Assay development using 3D3F10 for distinguishing CLU phosphorylation states.
• Evaluation of antibody performance in differentiating serum samples from dementia patients and controls.

Main Results:

• The 3D3F10 antibody distinguished dementia from non-dementia serum samples with high accuracy (AUC=0.897, sensitivity=81.8%, specificity=95.5%).
• The antibody did not differentiate Parkinson's disease samples, suggesting specificity for dementia.
• Findings indicated that phosphorylated CLU in dementia patients likely originates peripherally, not from the brain.

Conclusions:

• 3D3F10 is a novel tool for detecting modification-specific CLU.
• Non-phosphorylated CLU shows potential as a peripheral biomarker for dementia diagnosis.
• Peripheral phosphorylated CLU may contribute to the pathogenesis of dementia.