Neural stem cells derived from sporadic Alzheimer disease iPSCs exhibit excessive cell apoptosis and premature neuronal differentiation

摘要

OBJECTIVE To establish an in vitro cell model based on patient-specific human neural stem cells to study the pathomechanism of sporadic AD as well as screen candidate drugs.METHODS The peripheral blood cells from sporadic AD patients and cognitive normal controls were repro-grammed into inducedpluripotent stem cells(iPSCs),which were further induced into neural stem cells and neurons. The cell growth curve during the differentiation process was recorded by the IncuCyte ZOOM, and neural stem cells and neurons were identified by immunofluorescence. The apoptosis of neural stem cells and neurons was detected by Click-iT?Plus TUNEL Assay. RESULTS Neural stem cells derived from AD patients and cognitive normal controls can express neural stem cell markers Nes-tin,Sox1,Sox2 and Ki67.TUNEL assay results showed that the number of TUNEL-positive cells in neu-ral stem cells derived from AD patients was significantly higher than that of cognitive normal controls (P<0.01). When neural stem cells were differentiated into neurons, the percentage of MAP2 positive cells in the neural stem cell-derived culture dish of AD patients was significantly higher than the cogni-tive normal controls at day 16 of neuronal differentiation (P<0.01); the TUNEL assay showed that the number of TUNEL-positive cells in AD-derived neurons was significantly greater than that in cognitive normal controls (P<0.01) at day 16 of neuronal differentiation. CONCLUSION Our study revealed that AD-iPSC-derived neural stem cells exhibit premature neuronal differentiation and increased neural apoptosis,which might be relevant to the neuronal loss of AD,thus may provide valuable new tools to screen candidate drugs for the disease and to discover the mechanisms underlying AD pathogenesis.