A Network Toxicology Framework for Identification of Immune System Disruption by Per- and Polyfluoroalkyl Substance (PFAS) Mixture: In Silico Analysis

Per- and polyfluoroalkyl substances (PFAS) are persistent, chemically stable compounds widely used in daily life. Perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorohexanesulfonic acid (PFHxS), and perfluorooctanesulfonic acid (PFOS) were identified as the most relevant PFAS due to their prevalence and toxicity. This study aimed to investigate the immunotoxic mechanisms of a mixture of these PFAS using an in silico approach. Comparative Toxicogenomic Database (CTD), GeneMANIA, CytoHubba (Cytoscape), ToppGene Suite, and Metascape were used for the analysis. A total of 65 immune-related genes were identified as common to all four PFAS, with IFNG, TNF, IL1B, IL6, TYK2, CD3E, CASP8, VAV1, ARHGAP4, and CARD11 emerging as key hub genes. CTD phenotype analysis indicated immune dysregulation, with decreased humoral and adaptive immune responses in humans and tissue-specific modulation of B- and T-cell activity in mice, while no immune-related phenotypes were observed for PFNA. Network analysis identified functional modules associated with apoptotic and immune signaling, endothelial cell migration and angiogenesis, and shared inflammatory and viral response pathways. Disease enrichment analysis associated PFAS with autoimmune disorders (rheumatoid arthritis, asthma), metabolic conditions, and cardiovascular diseases (experimental diabetes, hypertensive disease). These results highlight PFAS involvement in immune modulation, cytokine signaling, and disease susceptibility.