Identification of proliferating neural progenitors in the adult human hippocampus.

Continuous adult hippocampal neurogenesis is involved in memory formation and mood regulation but is challenging to study in humans. Difficulties finding proliferating progenitor cells called into question whether and how new neurons may be generated. We analyzed the human hippocampus from birth through adulthood by single-nucleus RNA sequencing. We identified all neural progenitor cell stages in early childhood. In adults, using antibodies against the proliferation marker Ki67 and machine learning algorithms, we found proliferating neural progenitor cells. Furthermore, transcriptomic data showed that neural progenitors were localized within the dentate gyrus. The results contribute to understanding neurogenesis in adult humans. Editor's summary: Whether adult neurogenesis occurs in the human hippocampus is one of the most debated issues in neuroscience. Dumitru et al. used a single-cell transcriptomic approach to address this issue in human samples of various ages from birth through adulthood (see the Perspective by Quiniou and Jessberger). Machine learning algorithms helped the authors to identify proliferating neural progenitor cells in the adolescent and adult human hippocampus that resembled progenitor cells found in mouse and pig. The results support the idea that adult neurogenesis occurs in the human hippocampus and add valuable insights of scientific and medical interest. —Mattia Maroso [ABSTRACT FROM AUTHOR]