Comment on "Extracellular Vesicles Slow Down Aβ(1-42) Aggregation by Interfering with the Amyloid Fibril Elongation Step".

Halipi et al. explored the impact of extracellular vesicles (EVs) on amyloid-β (Aβ) aggregation. They concluded that EVs reduce Aβ aggregation, as seen by shorter and thicker fibrils. While we agree with the complex role of EVs in Alzheimer's disease, we are sceptical of the claim that EVs slow down Aβ aggregation, noting missing key references. Previous literature rather suggests that EVs (derived from neuronal cell lines) accelerate the process of Aβ fibrillation and plaque formation. Halipi et al.'s findings may be skewed due to the lack of essential neuronally expressed Aβ-binding partners, like the prion protein (PrP ^C ) in their EV samples. The commentary, in the light of included original experiments and cited literature, suggests that membrane proteins like PrP ^C are crucial to fully understand the role of EVs in Aβ aggregation, and Halipi et al.'s conclusions should be reexamined in light of these factors.