A quarterly publication of the Autism Research Institute

The Autism Research Review International is quarterly publication of the Autism Research Institute

Spring, 2021 | Number 2, Volume 35

Study offers insights into large head size in ASD

Severe forms of autism spectrum disorder (ASD) are often associated with large head size, and many individuals with ASD and a large head size have a deletion in a small piece of chromosome 16 known as 16p11.2. (See related article on page 6). A new study casts light on the association of this chromosome deletion with ASD and enlarged head size. 

Jingling Li and colleagues studied two types of neural stem cells—neural progenitor cells and oligodendrocyte progenitor cells—derived from individuals with the 16p11.2 deletion and control subjects. The researchers found that CD47, a protein that signals “don’t eat me,” was overexpressed in both types of cells from people with 16p11.2 deletion syndrome. As a result, unhealthy cells were eliminated at lower rates by the immune system. 

The researchers also found that the neural cells of people with 16p11.2 duplication syndrome exhibited increased cell surface expression of calreticulin, an “eat me” signal. However, this signal appears to be overridden by the high levels of CD47. 

The researchers discovered that blocking CD47 restored the normal elimination of unhealthy neural cells. They conclude, “These findings suggest that targeting the CD47 pathway may be helpful in identifying treatments for psychiatric disorders associated with brain overgrowth.”


Citations

“Overexpression of CD47 is associated with brain overgrowth and 16p11.2 deletion syndrome,” Jingling Li, Thomas Brickler, Allison Banuelos, Kristopher Marjon, Anna Shcherbina, Sravani Banerjee, Jing Bian, Cyndhavi Narayanan, Irving L. Weissman, and Sundari Chetty, Proceedings of the National Academy of Sciences, April 2021 (free online). Address: Sundari Chetty, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, [email protected]