Stably-transfected sNEP-NSCs remain multipotent and efficiently degrade Aβ. (A) Western blot analysis of control (C) and sNEP (+) stably-transfected NSCs (+) reveal high levels of sNEP expression versus control transfected NSCs (quantified in B). Notably, sNEP expression has no effect on markers of NSC multipotency (sox-2, nestin and musashi-1) and does not alter NSC BDNF expression (quantified in C). To determine whether sNEP-expressing cells can degrade Αβ, cultures were treated with recombinant human Aβ42 peptide and 48 hours later, conditioned media were collected and Aβ levels measured by sandwich ELISA. (D) sNEP-expressing NSCs efficiently reduced Aβ levels within conditioned media by more than 50% (P = 0.0008). (E) When NSCs are cultured without mitogen, both control and sNEP-expressing NSCs differentiate into neurons (red, β3-tubulin) and glia (blue, GFAP). N = 10 wells/group, error bars represent standard error of the mean (SEM). Scale Bar = 20 μm. Aβ, beta- amyloid; BDNF, brain-derived neurotrophic factor; GFAP, glial fibrillary acidic protein; NSCs, neural stem cells; sNEP, secreted neprilysin.