PICALM and Alzheimer disease: In Picalm+/− mice there was a 61% reduction in Aβ42 efflux from the brain, whilst in AD-derived human brain endothelial cells the same group demonstrated a 35% reduction in PICALM expression and a 50% reduction in Aβ transcytosis, which could be recovered with adenoviral-mediated PICALM expression [25].