Identification of Novel Biomarkers in Autism Spectrum Disorder for Early Diagnosis and Molecular Stratification

Autism spectrum disorder (ASD) comprises a range of complex neurodevelopmental conditions characterized by impaired social and communication skills, along with repetitive and restrictive behaviors or interests. The growing prevalence of ASD and its diverse clinical manifestations necessitate a multidimensional approach toward investigating the disorder. Currently, there are no approved biomarkers for ASD diagnosis, and the current gold standard diagnostic method relies on subjective evaluations by medical professionals. Thus, there is an urgent need to identify a robust and objective set of biomarkers to support the current diagnostic methods. In this study, we propose that utilizing proteomics and autoantibodies blood profiling of ASD cases and healthy controls could identify potential diagnostic biomarkers and dysregulated pathways implicated in ASD pathogenesis. Two high-throughput platforms, Olink and Sengenics, were employed to measure proteins and autoantibodies levels in the blood; bioinformatics and statistical analyses were performed to analyze the findings.

Our blood profiling revealed the presence of differentially expressed proteins in ASD individuals, some of which exhibited excellent accuracy in distinguishing ASD cases from healthy controls. In addition, gene ontology enrichment and weighted gene co-expression analysis (WGCNA) highlighted the presence of convergent novel pathways in ASD cases: the SNARE vesicular transport and ErbB signaling pathway. Furthermore, we identified significant dysregulation of seven neuronal-specific proteins, including NEFL, APP, and α-synuclein, which are known to be implicated in neurodegenerative processes. Moreover, autoantibodies profiling uncovered the presence of autoantibodies reactive against proteins involved in axonal guidance, synaptic function, amino acid metabolism, and chromatin binding.

Notably, the concentration of those autoantibodies showed an overall decline with increasing age of children with ASD. To the best of our knowledge, this is the first study that utilizes Olink and Sengenics high-throughput platforms for blood profiling of individuals with ASD, both globally and in the Middle East. These findings hold significant promise for advancing ASD research and may contribute to identifying reliable biomarkers for ASD diagnosis and improve the current understanding of its underlying mechanisms.