Scientists Grow Model of a Human Brain
Researchers from the Institute of Molecular Biotechnology in Vienna, Austria, have used stem cells to grow a three-dimensional, self-organising model of a developing human brain.
This system could potentially be used to model neurological diseases in a real human brain, offering advantages over the use of animal models that may not develop in the same way.
The researchers refer to the model created as a ‘cerebral organoid’. It has features that mimic the early developing human brain and specific regions are present, including the dorsal cortex, the ventral forebrain and an immature retina.
To date, this is the most complex in vitro human brain tissue. Early signs of the cortical layers can be identified, although the complete six-layer human cortex and all its complexities cannot be developed.
Embryonic stem cells and induced pluripotent stem cells (derived from adult human skin or blood cells) were used to grow the organoids. Most grow to a size of three or four millimetres, which is approximately the same size as the brain of an embryonic human at 9 weeks gestation.
Juergen Knoblich, the coordinator of the study, said that despite its appearance being similar to brain tissue in the early stages of development and despite the presence of active neurons, the organoid does not replicate naturally developing tissue. He likened the project to building a car with wheels and an engine, but with the engine on the roof: the car wouldn’t be driveable, but you could still analyse how it worked.
Cerebral organoids may be used to better understand diseases such as microcephaly and, potentially, disorders such as schizophrenia and autism.