Complex brain tissue developed in lab
Scientists at the Institute of Molecular Biotechnology of the Austrian Academy of Sciences have successfully developed complex human brain tissue has been successfully developed in a three-dimensional culture system.
By fine-tuned growth conditions and providing a conducive environment, intrinsic cues from the stem cells guided the development towards different interdependent brain tissues. Using these ‘mini brains’, the scientists were also able to model the development of a human neuronal disorder and identify its origin – opening up routes to long hoped-for model systems of the human brain.
Dr Jürgen Knoblich, who led the research, explained: “We modified an established approach to generate so called neuroectoderm, a cell layer from which the nervous system derives. Fragments of this tissue were then maintained in a 3D culture and embedded in droplets of a specific gel that provided a scaffold for complex tissue growth. In order to enhance nutrient absorption, we later transferred the gel droplets to a spinning bioreactor. Within three to four weeks defined brain regions were formed.”
After two months, the mini brains reached a maximum size, but they could survive indefinitely (currently up to 10 months) in the spinning bioreactor. Further growth, however, was not achieved, most likely due to the lack of a circulation system and hence a lack of nutrients and oxygen at the core of the mini brains.
The new method also offers great potential for establishing model systems for human brain disorders. Such models are urgently needed, as the commonly used animal models are of considerably lower complexity, and often do not adequately recapitulate the human disease.
Dr Madeline Lancaster, team member and first author of the publication, concluded: “In addition to the potential for new insights into the development of human brain disorders, mini brains will also be of great interest to the pharmaceutical and chemical industry.
“They allow for the testing of therapies against brain defects and other neuronal disorders. Furthermore, they will enable the analysis of the effects that specific chemicals have on brain development.”
The research has been published in the journal Nature and is part-funded by the European Research Council.
