Nat Biotechnol 36, 432–441 (2018).
On the constant hunt for a better model of neurological disorders, biologists have taken a fresh approach. Typically, either human cell-culture or an in vivo rodent model is used to study diseases of interest. By developing a hybrid system that utilizes human pluripotent stem cells (hPSC) in mouse hosts, investigators were seeking the advantages -relevance and complexity- of both systems. For this report, authors first converted hPSC to a cerebral organoid, a 3D cell culture, before implanting it in a mouse brain. Researchers saw development and integration of the organoid with native tissues. Grafts engaged in neurogenesis and produced electrically active cells that interacted with mouse neurons; additionally, glial cell development was observed. Importantly, grafts showed healthy vascularization by host tissues, one of the major shortcomings of working with just cell culture systems.