Scientists Juergen Knoblich and Madeline Lancaster at Austria's Institute of Molecular Biotechnology and fellow researchers at Britain's Edinburgh University Human Genetics Unit have succeeded in creating the first ”mini brains” using human stem cells.
Known as “cerebral organoids,” the researchers hope that the organs will help them gain better understanding of what causes of brain disorders such as autism, schizophrenia and intellectual disabilities, by allowing them to replicate three dimensional versions of tissues from different regions of the brain, including a “biological model of how a rare brain condition called microcephaly develops.”
"This study offers the promise of a major new tool for understanding the causes of major developmental disorders of the brain, as well as testing possible treatments," said Paul Matthews, a professor of clinical neuroscience at Imperial College London, who was not involved in the research.
To start, Knoblich and Lancaster grew human stem cells into tissue called neuroectoderm, described as “the layer of cells in the embryo from which all components of the brain and nervous system develop.” Bits of the neuroectoderm were then embedded in a scaffold and put into a spinning bioreactorm which bathed them in oxygen and other nutrients that permitted them to develop into the mini brains.
According to their report, the fragments organized themselves into primitive structures that could be recognized as developing brain regions such as retina, choroid plexus and cerebral cortex within a single month. After 60 days, the organoids reached a maximum size of around 0.16 inches.
"This is one of the cases where size doesn't really matter,” stated Knoblich. “ Although they were very small and still a long way from resembling anything like the detailed structure of a fully developed human brain, they did contain firing neurons and distinct types of neural tissue.”
"Our system is not optimized for generation of an entire brain and that was not at all our goal. Our major goal was to analyze the development of human brain (tissue) and generate a model system we can use to transfer knowledge from animal models to a human setting."
However, he and his team were quick to acknowledge that they have a long way to go before they are able to grow a fully functioning brain in their lab.