Journal Article

Cell diversity and network dynamics in photosensitive human brain organoids

Maria, Natalie, Williams, Ziv M., Macosko, Evan Z., Boyden, Edward S., Quadrato, Giorgia, Scholvin, Jorg, Goldman, Melissa, Min Yang, Sung, Berger, Daniel R., Sherwood, John L., Lichtman, Jeff W., Arlotta, Paola, McCarroll, Steven A., Nguyen, Tuan, Kinney, Justin P.

2017

Overview

In vitro models of the developing brain such as three-dimensional brain organoids offer an unprecedented opportunity to study aspects of human brain development and disease. However, the cells generated within organoids and the extent to which they recapitulate the regional complexity, cellular diversity and circuit functionality of the brain remain undefined. Here we analyse gene expression in over 80,000 individual cells isolated from 31 human brain organoids. We find that organoids can generate a broad diversity of cells, which are related to endogenous classes, including cells from the cerebral cortex and the retina. Organoids could be developed over extended periods (more than 9 months), allowing for the establishment of relatively mature features, including the formation of dendritic spines and spontaneously active neuronal networks. Finally, neuronal activity within organoids could be controlled using light stimulation of photosensitive cells, which may offer a way to probe the functionality of human neuronal circuits using physiological sensory stimuli. Long-term cultures of human brain organoids display a high degree of cellular diversity, mature spontaneous neuronal networks and are sensitive to light. Enlightening organoids Three-dimensional cellular models of the human brain, or organoids, enable the in vitro study of cerebral development and disease, but exactly which cells are generated and how much of the brain's complexity they recreate is undefined. To investigate in depth the nature of cells in human cerebral organoids differentiated from pluripotent stem cells, Paola Arlotta and colleagues carried out droplet-based single-cell expression analysis on cells isolated from over 30 organoids at developmental stages ranging from 3 to 9 months and beyond. They identify a wide diversity of neurons and progenitors and show that the more mature organoids formed dendritic spines as well as electrically active networks, which responded to light stimulation. The authors suggest that organoids may facilitate the study of circuit function using physiological sensory mechanisms. Elsewhere in this issue, Sergiu Paşca and colleagues show that re-assembling ventral and dorsal forebrain spheroids obtained separately in vitro allows the migration of human interneurons and the formation of functional synapses.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 101/28 / 101/62 / 13 / 13/106 / 13/51 / 14 / 14/63 / 38 / 631/378 / 631/378/2183 / 631/532/2064/2158 / 9/30 / Biodiversity / Brain / Brain - cytology / Brain cells / Brain research / Cell Line / Cell Separation / Cerebral cortex / Cerebral Cortex - cytology / Cerebral Cortex - metabolism / Circuits / Dendrites / Dendritic spines / Developmental biology / Gene expression / Gene Expression Profiling / Humanities and Social Sciences / Humans / In Vitro Techniques / Light / multidisciplinary / Nerve Net - cytology / Nerve Net - radiation effects / Neural networks / Neural Pathways - cytology / Neural Pathways - physiology / Neural Pathways - radiation effects / Neurogenesis / Neurons / Organ Specificity / Organoids / Organoids - cytology / Organoids - growth & development / Organoids - radiation effects / Photoreceptor Cells, Vertebrate - cytology / Photosensitivity / Physiological aspects / Pluripotent Stem Cells - cytology / Retina / Retina - cytology / Retina - metabolism / Science / Sensory stimuli / Sequence Analysis, RNA / Single-Cell Analysis / Somatosensory cortex / Stem cells / Time Factors / Transcriptome