Minibrain Storm : Cerebral Organoids Aren't Real Brains?But They Provide a Powerful Platform for Modeling Brain Diseases Like Zika Infection, Alzheimer's, and Even Autism

Floating in a Petri dish, they look like tiny tapioca pearls in peach broth, a couple dozen in number and none much larger than the tip of a ballpoint pen. But under a microscope, dense, lumpy bodies come into focus, outlined by wispy coronas. Cerebral organoids make no attempt to replicate true brains, but they do represent a more complex, brain-like model than researchers have ever had before. This is crucial because many diseases of the brain are too complex to be accurately represented in a flat culture, where the circuitry and interplay of cell types in 3-D space are impossible. Even something as simple as modeling basic Alzheimer's pathology doesn't work well in such cultures because the signature protein tangles diffuse into the media. Similarly, mouse models, as useful as they are for behavioral studies, have cells that operate on different schedules, lack an elaborate neocortex, and don't spontaneously develop human conditions like autism, schizophrenia, and microcephaly. Organoids not only have the potential to break these limits-in some cases, they already have.