Plasma tau is increased in frontotemporal dementia

Area of Science:

• Neurodegenerative diseases
• Biomarker discovery
• Tau pathology

Background:

• Frontotemporal dementia (FTD) is a heterogeneous neurodegenerative disorder with behavioral or language symptoms.
• Major genetic causes include mutations in GRN, MAPT, and C9orf72.
• Lack of reliable biomarkers to distinguish FTD pathologies, like tau and TDP-43, during life.

Purpose of the Study:

• To measure plasma tau concentrations in FTD patients and healthy controls.
• To investigate associations between plasma tau and clinical/genetic FTD subtypes.
• To explore correlations with disease severity and progression markers.

Main Methods:

• Ultrasensitive single molecule methodology used to quantify plasma tau.
• Study included 176 participants: 71 with behavioral variant FTD (bvFTD), 83 with primary progressive aphasia (PPA), and 22 controls.
• Analysis involved group comparisons and correlative analyses with disease severity measures.

Main Results:

• Plasma tau concentrations were higher in bvFTD and PPA groups compared to controls.
• All PPA subtypes showed significantly elevated plasma tau versus controls.
• Only the MAPT genetic mutation group exhibited significantly increased plasma tau levels.

Conclusions:

• Plasma tau is increased in FTD across clinical presentations, but only in MAPT genetic mutations among genetic subtypes.
• MAPT mutations are associated with tau pathology, suggesting plasma tau's potential as a biomarker.
• Further research in pathologically confirmed FTD cohorts is needed to validate plasma tau for differentiating tau pathology.