Q Could a living creature be made using only stem cells?
— Joshua Sampson, Middleton, Wis.
A Bill Murphy, co-director of stem cell and regenerative medicine center and professor in biomedical engineering and orthopedics and rehabilitation at University of Wisconsin-Madison:
Stem cells are special cells inside your body that can multiply indefinitely, or make copies of themselves. They can also differentiate, meaning they can become every cell type that’s present in your body.
Generating a living creature requires not just the cells, but also the environment that allows full development to happen. It requires a womb, a place in which the organism can develop. That doesn’t happen outside the body.
There are aspects of development that we can re-create outside the body, but it doesn’t result in the creation of an organism. It results in the creation of some specific tissue type or some specific cell type.
A good example is a tissue chip project that scientists at UW-Madison have worked on, trying to generate microscale mimics of the brain. These are very small, about the size of a pinhead in many cases. They’re forming into tissues that are similar to aspects of the human brain.
These are not full human brains on a chip, but they have similar features. Some of the first research being done is determining the effect of chemicals on the developing human brain.
The brain mimics are exposed to potential toxins and potential non-toxins to get a sense of whether scientists can predict if a chemical will be toxic or nontoxic to the developing human brain.
Other important uses of the tissue chips, outside of toxicology, are disease modeling and drug discovery.
In disease modeling, cells are taken from patients who have neurodevelopmental or neurodegenerative disorders. Brain mimics are developed from those cells.
The brain mimics can be used to better understand how those diseases develop and how those diseases can best be treated.