A Caltech Library Service

Brain, Gut and Immune Interactions in Autism Spectrum Disorder


Hsiao, Elaine Yih-Nien (2013) Brain, Gut and Immune Interactions in Autism Spectrum Disorder. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/DEVQ-1P16.


Autism spectrum disorder (ASD) is a class of complex neurodevelopmental disabilities that are characterized by the presence and severity of stereotyped behaviors, impaired communication, and abnormal social interactions. The incidence of autism has rapidly increased to 1 in 88 children in the United States, making ASD one of the most significant medical and social burdens of our time. However, drugs are often used to treat autism-related conditions, including anxiety, hyperactivity, epilepsy, and obsessive-compulsive behaviors, and therapies for treating the core symptoms of autism are limited. Moreover, molecular diagnostics are not available for the reproducible identification of ASD; as yet, the disorder is diagnosed based on standardized behavioral assessments. Much research into ASD has focused on genetic, behavioral, and neurological aspects of the illness. However, primary roles for environmental risk factors and peripheral disruptions, such as immune dysregulation and gastrointestinal distress, have gained significant attention.

The work described in this thesis uncovers molecular mechanisms involved in the pathogenesis of autism-related endophenotypes in a mouse model of a primary autism risk factor, maternal immune activation (MIA). MIA is founded upon the strong epidemiological link between maternal infection and increased autism risk in the offspring. This risk factor can be translated to a mouse model with face and construct validity for autism, wherein pregnant mice injected with the immunogenic, double-stranded RNA poly(I:C) yield offspring with the core behavioral and neuropathological features of autism. Specifically, we report that MIA critically alters placental immune status and endocrine function, reflecting a key pathway by which fetal development may be disrupted to manifest in ASD-related phenotypes. We identify signature changes to the fetal brain transcriptome in response to multiple modes of MIA, highlighting a converging pathway involved in the development of autism-related behaviors and neuropathologies. We characterize peripheral, neural, and enteric immune alterations in MIA offspring and uncover an immune contribution to autism-related behavioral abnormalities. Finally we demonstrate that a microbe-based therapeutic can ameliorate intestinal pathology, metabolic function, and autism-related behaviors in MIA mice, which supports a role for the gut-immune-brain axis in ASD.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:autism, immunity, gastrointestinal, microbiome
Degree Grantor:California Institute of Technology
Major Option:Biology
Awards:Everhart Distinguished Graduate Student Lecture Series, 2013.
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Patterson, Paul H.
Thesis Committee:
  • Mazmanian, Sarkis K. (chair)
  • Rothenberg, Ellen V.
  • Anderson, David J.
  • Patterson, Paul H.
Defense Date:12 December 2012
Funding AgencyGrant Number
National Institute of Mental HealthUNSPECIFIED
Simons FoundationUNSPECIFIED
U.S. Dept. of DefenseUNSPECIFIED
Record Number:CaltechTHESIS:12172012-110932095
Persistent URL:
Related URLs:
URLURL TypeDescription adapted for ch. 4 adapted for ch. 5 adapted for ch. 7 adapted for ch. 8 adapted for ch. 9 adapted for ch. 10 DOIArticle adapted for ch. 11 material for ch. 9
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7337
Deposited By: Elaine Hsiao
Deposited On:14 Jan 2014 21:54
Last Modified:03 Oct 2019 23:57

Thesis Files

PDF - Final Version
See Usage Policy.


Repository Staff Only: item control page