MME and early-onset autosomal dominant Alzheimer disease: Furthermore, Katsuda et al. [88] have demonstrated that exosomes secreted by ASCs contained enzymatically active neprilysin (neutral endopeptidase: NEP or CD10), involved in the degradation of β-amyloid peptide (Aβ) whose accumulation in the brain plays a critical role in Alzheimer's disease pathogenesis.