Inflammatory Cytokines: Potential Biomarkers of Immunologic Dysfunction in Autism Spectrum Disorders

Abstract

Autism is a disorder of neurobiological origin characterized by problems in communication and social skills and repetitive behavior. After more than six decades of research, the etiology of autism remains unknown, and no biomarkers have been proven to be characteristic of autism. A number of studies have shown that the cytokine levels in the blood, brain, and cerebrospinal fluid (CSF) of autistic subjects differ from that of healthy individuals; for example, a series of studies suggests that interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) are significantly elevated in different tissues in autistic subjects. However, the expression of some cytokines, such as IL-1, IL-2, transforming growth factor-β (TGF-β), and granulocyte-macrophage colony-stimulating factor (GM-CSF), is controversial, and different studies have found various results in different tissues. In this review, we focused on several types of proinflammatory and anti-inflammatory cytokines that might affect different cell signal pathways and play a role in the pathophysiological mechanism of autistic spectrum disorders.

Peripheral Inflammatory Markers Contributing to Comorbidities in Autism

“…IL-1β plays a key role mediating severe placental damage and neurodevelopmental anomalies in offspring [44]. From this point of view, our results reinforce its potential involvement in the physiopathology of autism.…”

Immune dysfunction and neuroinflammation in autism spectrum disorder

“…Innate immunity, therefore, plays a fundamental role in ASD development. Innate immunity-related cytokines and chemokines are altered in ASD compared with controls, and suggest these molecules may be used as ASD risk immune markers (Zerbo et al 2014, Masi et al 2015, Xu et al 2015. Alternative mRNA splicing disorder in ASD may explain some impairment in monocyte/macrophage and natural killer cells (Stamova et al 2013).…”

Transcriptome profiling analysis of rare minnow (Gobiocypris rarus) gills after waterborne cadmium exposure

“…Therefore, we hypothesized that inflammation is induced after sub-chronic Cd exposure. TNF-α, IL1β, IL6, and NF-κB are commonly used biomarkers of inflammation (Elsabahy and Wooley, 2013;Xu et al, 2015), and TNF-α, IL1β, and IL6 are predominant pro-inflammatory cytokines in fish (Kum and Sekkin, 2011). The significant up-regulation of TNF-α, IL1β, and NF-κB by treatment with higher doses of Cd suggests an inflammatory response.…”