CPE and Alzheimer disease: In experiments with mice, Xiao et al. (2023) found that early hippocampal delivery of AAV carrying the gene for Neurotrophic factor-α1/Carboxypeptidase E (NF-α1/CPE) in 3xTg-AD male mice could prevent the later development of cognitive deficits, neurodegeneration, and excessive tau phosphorylation.