Blood testing for Alzheimer's diagnosis: getting closer.

The importance of the early detection of Alzheimer's disease (AD), especially at the stage of mild cognitive impairment (MCI), is increasingly recognized for the early management and intervention of the disease.

However, the existing diagnostic methods, through cognitive assessments, brain imaging or measurement of biomarkers in the cerebrospinal fluid, are either subjective, expensive or invasive, while patients are often diagnosed after the manifestation of symptoms and miss the golden window for intervention.

The plasma proteome is altered in patients with AD, suggesting the feasibility of developing a robust blood test for screening and staging of AD.

In a new study the authors conducted a comprehensive profiling of the plasma proteome of MCI by measuring 1,160 proteins in a Hong Kong Chinese cohort, to identify novel blood biomarkers for MCI and early AD.

They identified 496 proteins that were dysregulated in MCI plasma, and they showed that those MCI-associated plasma proteins, involved in different biological processes such as innate immune response, cell adhesion and inflammation, exhibited distinct dysregulating patterns upon the disease progression.

Finally they identified a panel of 18 plasma proteins that can capture the profile changes of plasma proteome in MCI and AD.

They showed that this 18-protein panel achieves highly accurate classification of MCI (AUC = 0.913-0.925) and AD (AUC = 0.970-0.993) in two independent cohort.

This study comprehensively profiled the MCI plasma proteome and demonstrates the feasibility of a blood-based biomarker panel for the early screening and classification of MCI and AD in clinical settings.

Source. Neuroscience 2023 (Y. JIANG et al.)