Quantitative Proteomics Reveals Protein Dysregulation During T Cell Activation in Multiple Sclerosis Patients

Multiple sclerosis (MS) is an autoimmune, neurodegenerative disorder with a strong genetic component that acts in a complex interaction with environmental factors for disease development. CD4+ T cells are pivotal players in MS pathogenesis, where peripherally activated T cells migrate to the central nervous system leading to demyelination and axonal degeneration. In the current study, we evaluated dysregulation of CD4+ T cell activation at the protein level using electrospray liquid chromatography-tandem mass spectrometry to get insights into immune-cell processes in MS. Our study highlights the importance of CD4+ T cell activation for MS, as proteins that change in abundance upon T cell activation are enriched for proteins encoded by MS susceptibility genes. Our results provide evidence for proteomic disturbances in T cell activation in MS, and pinpoint to dysregulation of the Nur77 pathway, a biological pathway known to limit aberrant effector T cell responses.