MS is an autoimmune inflammatory disease where the layer that insulates neurons, myelin, is destroyed by invading immune cells. In animal models of MS, immune cells get access to the central nervous system (CNS) through the choroid plexus (CP). In the last decade, breakthrough findings put CP at the forefront for brain homeostasis, as it constitutes a gateway of leukocyte trafficking participating in immune surveillance of the CNS. Nonetheless, the role of CP in the pathogenesis of MS remains largely unknown. In this project we aim to perform OMICS in human tissue from control and MS patients. We anticipate our approach will clarify critical aspects of MS establishment and progression, and will uncover MS biomarkers.