NEP gene delivery studies have suggested that not only intracerebral injections of NEP-bearing constructs can have an antiamyloid effect in AD animal models [87] but that intraperitoneal injections of a lentivirus vector expressing NEP fused with the ApoB transport domain could also reduce Aβ burden and increase synaptic density in the brain of AD transgenic mice [106]. This evidence concerns the gene APOB and Alzheimer disease.