Stem Cells – A New Frontier in Autism Research
Daniel Lightfoot, Ph.D., Director of the Autism Tissue Program
Ricardo Dolmetsch, Ph.D. has a vision for autism research. Using pluripotent stem cell (iPSC) technology to create rare stem cells from other “common” cells of the human body cells, Dolmetsch and his lab at Stanford study neurodevelopmental disorders such as autism.
Unlike embryonic stem cells or adult stem cells which are isolated from existing and often difficult to obtain tissues, iPSC’s are “created” from easy to obtain and plentiful sources, such as skin or hair samples. This is accomplished through a unique process where cells are developmentally regressed to an earlier state.
To appreciate the concept of a stem cell, consider a seed. As a single cell it holds the potential to grow into an adult plant. It is a “stem cell” – one that can change or develop into any cell of the plant, from a leaf cell, to a flower cell or into a root cell. Through iPSC technology, this process is reversed. Scientists can developmentally regress an adult cell into an earlier cell like a seed. In short, scientists can turn a piece of a leaf into a seed, which could then grow into any cell of the plant. Though this does not at all imply that science can create a whole person from a skin sample, it does, however, allow researchers to easily create a variety of cells that can then be used for scientific study.
Once stem cells are created, they can be induced to develop into brain cells. For the first time, scientists are directly studying living brain cells in the lab. How these cells grow, interact, communicate, organize into groups and what helps or impairs these cells’ growth is now being more effectively studied. Additionally, stem cells have the unique ability to replicate without changing, meaning that from a single skin or hair sample many cells can be created. This allows a near limitless source of resources for scientific inquiry.
Dolmetsch shared this vision at a keynote presentation at IMFAR. He and his colleagues have now created an entire repository of stem cells from individuals with neurodevelopmental disorders. By comparing autism brain cells, with Timothy Syndrome and other disorders, the research team is not only learning about the differences among these conditions, but also the commonalities. Once the brain cell is created, it is possible to experiment with different compounds to determine whether they can restore neuronal function. Thus, stem cells provide a platform for drug screening. A deeper understanding of these disorders will also contribute more generally to a fundamental appreciation of how the human brain works.