| dc.description.abstract | Multiple Sclerosis (MS) is a chronic inflammatory and neurodegenerative disease of the central nervous system (CNS) and is the leading cause of neurological disability in young adults in North America and Europe, affecting approximately 2.5 million people worldwide. The pathological features associated with MS include neurodegeneration and brain atrophy, axonal loss, cortical demyelination, microglia activation, and a failure of remyelination. The cerebrospinal fluid (CSF) is referred to as the “mirror of the brain”, and recent studies have shown that biomarkers reflecting inflammation and the stages of MS can be found in the CSF. The CSF contains immune cells, especially under pathological conditions. Recent studies have observed microglia cells in the CSF of individuals with relapsing remitting MS using single cell RNA sequencing. The study showed evidence that microglia of individuals with relapsing remitting MS may have the capability to migrate from the central nervous system into the CSF. Microglia are the resident macrophage of the central nervous system and are intricately bound to mechanics of neurological diseases by producing both neuroprotective and neurotoxic effects depending on stimuli. Characterising CSF cells and particularly microglia in depth is challenging and advances in new technologies allow to phenotype these cells at unprecedented resolution. We aimed at characterising the immune cells in CSF of relapsing MS patients in detail. By utilizing our groups expertise with Imaging mass cytometry, we developed and optimised a protocol for capture and analysis of CSF cells from single cell suspension. For this protocol an imaging mass cytometry panel of metal conjugated antibodies was developed for high-dimensional immunophenotypic analysis of microglia. Focusing on microglial cells, we possibly detected these cells in CSF and performed analysis using specific microglial markers and general immune markers. The analysis was performed alongside controls for characterisation, iPSCs-derived microglia, a commercial microglia cell line, PBMCs and buffy coats. Our results show the expression of various immune and microglia markers in cells of the CNS and controls. The iPSCs derived microglia and commercial cell line showed distinct expression of microglia markers and the same markers were detected in CSF cells of MS indicating that microglia may in fact be detected in CSF. Not all antibodies worked, and techniques need further optimisation for detections of both immune cells and microglia. The procedure we developed shows great potential to analyse CSF cells and needs further optimisation in order to characterise and distinguish neuroprotective and neurotoxic microglial cells in the CSF. The approach developed in this thesis will expand the understanding of the central nervous system immune architecture in relapsing MS patients. | |
