The biological constructs have been termed “mini-brains” by the research group behind the project. These are three-dimensional, ball-shaped structures that form over an eight week period. The structures are very small, and not really visible to the human eye (they resemble the size of a small fly.)
The brains were formed from induced pluripotent stem cells. The cells were genetically reprogrammed to an embryonic stem cell-like state. Next the cells were stimulated to grow into brain cells, a process which takes about two months to complete. This process allows for hundreds of replica min-brains to be made in one batch. The mini-brains are functional, showing spontaneous electrophysiological activity as recorded by a device similar to an electroencephalogram. The electrophysiological is akin to the neuron function of a normal brain.
Having successfully created these min-brains, the research group thinks it will be able to generate certain genetic traits or replicate neurological diseases like Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis. They may also be able to replicate autism, according to the research brief. This is slightly controversial because the causes of autism are unknown and the condition is likely to be a combination of genetic and environmental factors (as Digital Journal reported recently.) Have engineered these conditions, the researchers will be able to undertake drug testing as part of the search for cures.
Other applications for the bundles of cells and neurons include examinations of viral diseases and a study of conditions like stroke, which affect the blood vessels of the brain.
By allowing different drugs to be screened, the mini-brains should also decrease the number of animals used in clinical research. Moreover, the results obtained could be more representative than the mice or rats used in neurological drug studies. This is because the mini-brains are composed of human cells and the reactions obtained should be closer to what happens in people.
The study was performed by Johns Hopkins University Bloomberg School of Public Health and presented to American Association for the Advancement of Science conference in Washington, DC during February 2016. The results of the study have yet to be published in a peer reviewed journal.
