LRP1 and Alzheimer disease: Studies in genetic modified mice with brain endothelial cell‐specific deletion of Lrp1 show reduced Aβ levels in the blood and elevated soluble Aβ in the brain, leading to deteriorations in spatial learning and memory.[70] Knockdown expression of LRP1 with antisense RNA in mice shows similar results.[122] Consistent with these results, in AD patients, LRP1 is also deficient in the BBB, contributing to slower clearance of Aβ.