Levels of TDP-43 and tau isoforms in plasma extracellular vesicles (EVs) can discriminate between different molecular subtypes of frontotemporal dementia (FTD), amyotrophic lateral sclerosis (ALS) and progressive supranuclear palsy (PSP), according to new research published in Nature Medicine. The findings indicate the potential of these measurements as minimally invasive biomarkers for the diagnosis and monitoring of these conditions.

EVs are released by many cell types, including neurons, and are known to contain TDP-43 and tau. To test whether concentrations of these proteins in EVs can be used to distinguish between the different pathological subtypes of FTD, Schneider and colleagues compared isolated EVs from the plasma of individuals with behavioural variant FTD (bvFTD) with samples from individuals with ALS, as a TDP-43-positive control, or PSP, as a 4-repeat (4R) tau-predominant control, alongside healthy control individuals.