Altered cytokine levels in the cerebrospinal fluid of adult patients with autism spectrum disorder

Background: Despite intensive research, the etiological causes of autism spectrum disorder (ASD) remain elusive. Immunological mechanisms have recently been studied more frequently in the context of maternal autoanti-bodies and infections, as well as altered cytokine profiles. For the detection of immunological processes in the central nervous system, analyses of cerebrospinal fluid (CSF) are advantageous due to its proximity to the brain. However, cytokine studies in the CSF of ASD patients are sparse.Methods: CSF was collected from a patient sample of 24 adults (m = 16, f = 8, age: 30.3 +/- 11.6 years) with ASD and compared to a previously published mentally healthy control sample of 39 neurological patients with idiopathic intracranial hypertension. A magnetic bead multiplexing immunoassay was used to measure multiple cytokines in CSF.Results: Significantly decreased interferon-gamma-induced protein-10 (p = 0.001) and monocyte chemoattractant protein-1 (p = 0.041) levels as well as significantly higher interleukin-8 levels (p = 0.041) were detected in patients with ASD compared with the control group. Conclusion: The main finding of this study is an altered cytokine profile in adult patients with ASD compared to the control group. This may indicate immune dysregulation in a subgroup of adult ASD patients. Further studies in larger cohorts that examine a broader spectrum of chemokines and cytokines in general are needed to detect possible specific immune signatures in ASD.