PHILADELPHIA — Autism is a neurodevelopmental disorder which creates difficulties with social interactions, communication, and repetitive behaviors. According to the Centers for Disease Control and Prevention, autism affects one in 54 children in the United States. Although autism typically isn’t diagnosed until children are at least 18 months-old, a new study finds that abnormal brain cell development likely occurs much earlier.
Researchers say this even occurs while babies are still in the womb.
To study developing brain cells, a team from King’s College London and Cambridge University use a type of cell known as an induced pluripotent stem cell (or iPSC). Essentially, iPSCs are adult cells that scientists force to become immature embryonic-like stem cells. Scientists can program iPSCs to become one of many different cell types, including neurons. Since iPSCs are forced to restart their cellular development, they mimic the processes occurring in the womb. This allows them to serve as a useful means of studying early brain development.
“Using iPSCs from hair samples is the most ethical way to study early brain development in autistic people,” explains study author Dwaipayan Adhya in a media release. “It bypasses the need for animal research, it is non-invasive, and it simply requires a single hair or skin sample from a person.”
Adhya is a molecular biologist at the Autism Research Centre in Cambridge and Department of Basic and Clinical Neuroscience at King’s College London.
Decoding the human ‘black box’ to understand autism
To create the iPSCs, the study analyzes hair samples from nine adults with autism and six neurotypical adults. The hair cells were then treated with growth factors (naturally occurring bodily substances that regulate cell division and survival). The authors looked at the cells’ appearance and genetic makeup at different phases of development.
The scientists’ results reveal iPSCs from neurotypical people look different from those participants with autism. At day nine, neurons from neurotypical people develop a characteristic pattern of “neural rosettes,” which have a dandelion-like shape. In contrast, cells from people with autism have smaller rosettes or don’t form them at all. Cells from autistic individuals also express lower levels of important developmental genes.
“The use of iPSCs allows us to examine more precisely the differences in cell fates and gene pathways that occur in neural cells from autistic and typical individuals,” co-author Deepak Srivastava explains. “These findings will hopefully contribute to our understanding of why there is such diversity in brain development.”
“The brain has been the ultimate black box. Here, the authors have used nerve cells derived from peripheral stem cells to peek inside this box. This important study suggests that this is possible and is deepening our understanding of autism,” says John Krystal, Editor-in-Chief of the journal Biological Psychiatry.
The study is published in the June 22 edition of Biological Psychiatry.