Last week we covered autoimmunity and autism in relation to the S100B protein. A University of Kansas Medical Center study has found significantly lower levels of several cytokines, the immune system’s messengers and regulators, in the plasma of children with autism disorder (AD) compared to that of unrelated healthy siblings from other families who had members with autism spectrum disorders (ASD).
In particular, of the 29 cytokine levels investigated, the researchers found disturbed levels in five related to the T-helper cell immune system and three involved in hematopoiesis or the production of blood cells possibly affecting antibody production required for normal functioning of the immune system.
Both the immune system and genetic factors have been implicated in the biological basis for autism, said Merlin G. Butler, professor of psychiatry at the KU Medical Center. “Our study further supports a disturbed immune system in children with classic autism that may be related to genetic factors as cytokine proteins are coded by genes distributed among the human chromosomes.”
Additionally, studies in families with autism have shown the significant contribution of genetics, including deletions and duplications of chromosomes and mutations or variants found in specific genes involved with brain development and function, he said.
“The importance of identifying early immunological disturbances that may contribute to autism has implications for identifying risk factors, diagnosis and possibly intervention as cytokines may play a role in the function of the developing brain,” he said.
The study was one of the largest of its kind to date, analyzing the plasma of 99 children with AD between 5 and 10 years of age and that of 40 age- and gender- matched unrelated healthy siblings without AD under the same clinical assessments, specimen processing and laboratory conditions. The male-to-female ratio closely matches that seen in the ASD population, and there were gender-based differences found in five cytokines.
Butler said that the purpose of this research is linking the genes encoding immune-related proteins and cytokines to ASD along with identifying the sequence of the events during critical periods of brain and neurological development. This could allow for earlier recognition, diagnosis and potential treatment.
Ann Manzardo, assistant professor of psychiatry, was the first author on the study. The study was published in the April 2012 International Journal of Developmental Neuroscience.