HUMANE · Transcriptional characterization of human postnatal and adult neural progenitors and of the stem cell niches.

The presence of adult neurogenesis in humans spurs hope for brain regeneration and changed the view of the brain as an immutable structure. Adult neurogenesis was found in almost all mammals and was extensively studied in rodents. In spite of the vast knowledge accumulated in the field, data describing human adult neurogenesis is controversial. Several studies found neural progenitors in the human brain. Conclusive data was brought by the Frisén group via 14C birthdating, which showed ongoing neurogenesis in the hippocampus and striatum. Other studies based mostly on immunohistological methods and rodent neurogenesis markers, failed to identify neural progenitors in the adult human hippocampus and even questioned the existence of a stem cell niche. These conflicting reports are a clear indication that we need unbiased descriptive studies of human adult neurogenesis. The recent advances in sequencing technologies allow an in-depth transcriptome characterization at a cellular level, making possible an unbiased identification of neural progenitors and of neurogenic niches. The aim of this project is to show beyond doubt whether neural progenitors and stem cell niches are present in the adult human brain using unbiased, state-of-the-art sequencing methods. Furthermore, for the first time we will characterize the transcriptome of single postnatal and adult neurogenic progenitors and of the potential stem cell niches. Our study will not only show whether adult neurogenesis takes place in humans but will also generate tools that will lay the foundation for future studies, boosting the research in the field. Rodent studies showed that adult neurogenesis contributes to brain plasticity, cognitive flexibility and can constitute a future start for regenerative therapies. Thus, our results could open the road for using neurogenesis to fight against neurological disorders especially visible in the aging European society such as age related cognitive decline or depression.