Guided self-organization recapitulates tissue architecture in a bioengineered brain organoid model

Abstract

Recently emerging methodology for generating human tissues in vitro has the potential to revolutionize drug discovery and disease research. Currently, three-dimensional cell culture models either rely on the pronounced ability of mammalian cells to self organize in vitro1-6, or use bioengineered constructs to arrange cells in an organ-like configuration7,8. While self-organizing organoids can recapitulate developmental events at a remarkable level of detail, bioengineered constructs excel at reproducibly generating tissue of a desired architecture. Here, we combine these two approaches to reproducibly generate micropatterned human forebrain tissue while maintaining its self-organizing capacity. We utilize poly(lactide-co-glycolide) copolymer (PLGA) fiber microfilaments as a scaffold to generate elongated embryoid bodies and demonstrate that this influences tissue identity. Micropatterned engineered cerebral organoids (enCORs) display enhanced neuroectoderm formation and improved cortical development. Furthermore, we reconstitute the basement membrane at later stages leading to characteristic cortical tissue architecture including formation of a polarized cortical plate and radial units. enCORs provide the first in vitro system for modelling the distinctive radial organization of the cerebral cortex and allow for the study of neuronal migration. We demonstrate their utility by modelling teratogenic effects of ethanol and show that defects in leading process formation may be responsible for the neuronal migration deficits in fetal alcohol syndrome. Our data demonstrate that combining 3D cell culture with bioengineering can significantly enhance tissue identity and architecture, and establish organoid models for teratogenic compounds.