Autism spectrum disorder (ASD) stands as a multifaceted neurodevelopmental enigma characterized by intricate disruptions in social interaction and the emergence of repetitive behaviors. While previous investigations have shed light on the pivotal role of immune dysregulation in ASD pathology, a comprehensive comprehension of single cell transcriptomic profiles within peripheral immune cells and their responsiveness to metabolic interventions remains a critical frontier. Herein, we embark on an illuminating ASD by meticulously unraveling the intricate tapestry of immune cell dynamics and their molecular orchestration. Employing omics methodologies, we unveil a captivating portrayal of extracellular vesicle-associated proteomic transformations and unveil a revelatory exploration of single-cell RNA sequencing profiles from peripheral blood mononuclear cells (PBMCs) in ASD individuals. Our investigations uncover a striking preponderance of CD4 T cells within the PBMC composition of ASD subjects, casting a new perspective on the immune landscape. Dissecting the transcriptional landscapes of these CD4 T cells, we discern an intriguing abundance of immature subsets, suggestive of an atypical developmental trajectory. Our study illustrates that the transcriptomic fingerprints of CD4 T cells may emerge as potent predictors of disease trajectory.