Immunopathology in PMM2-CDG: Defective glycosylation impact in the TNFα -TNFR1 signalling pathway

Glycosylation is a post-translational modification that plays a crucial role in immune system activity. Phosphomannomutase 2-Congenital Disorder of Glycosylation (PMM2-CDG) is a rare genetic disease affecting glycosylation with a multi-systemic impact. PMM2-CDG patients commonly show immune disfunction and elevated pro-inflammatory cytokine levels that may link to other symptoms. However, the underlying immune mechanisms remain unclear. Given Tumour Necrosis Factor (TNF)’s key role in inflammation, this study proposes that defective glycosylation of its receptors disrupts intracellular signalling, leading to changes in the immune response of PMM2-CDG patients. To address this, we applied an integrative approach, combining transcriptomics, glycomics, and immune-related assays to investigate the impact of TNF-a stimulation via TNF receptor 1 (TNFR1) in a cohort of PMM2-CDG patients’ skin fibroblasts.