Arc mediates intercellular tau transmission via extracellular vesicles.

Arc is essential for packaging tau into extracellular vesicles, significantly facilitating intercellular tau transmission in neuronal systems.

• Why it matters: Understanding how tau spreads between cells is crucial for developing interventions for tauopathies like Alzheimer's disease, where tau pathology propagates through the brain.
• What they did: The study used transgenic mice and human brain samples to show that Arc interacts directly with tau, promoting its incorporation into extracellular vesicles, with reduced tau transmission observed in Arc knockout models.
• The result: Disruption of Arc markedly decreases tau transfer via EVs, highlighting Arc as a key target for therapies aimed at halting tau spread and disease progression.