Transcriptome of self-reactive proliferating CD4+ T cells in multiple sclerosis

Multiple sclerosis (MS) is a T cell-mediated demyelinating autoimmune disease of the central nervous system causing neurological deficits with substantial disability. Our group demonstrated that self-reactive proliferation of peripheral lymphocytes is increased in MS patients, is associated genetic risk and is involved in the pathogenesis of MS. These observations are based on an established in vitro system, in which peripheral blood mononuclear cells (PBMC) were seeded out for 7 days in serum-free medium in the absence of an exogenous stimulus. In order to track the self-reactive proliferation, cells were labeled with the fluorescent proliferation marker CFSE. We further showed that in particular CD4+ T cells are increased in RRMS in remission and with HLA-DR15 serostatus, bear a pathogenic Th1 phenotype and are migrating preferentially to active brain lesions in MS. In order to understand the biological relevance of the proliferating cells on a molecular level, we sorted CD4+ T cells from the self-reactive proliferating (gating: singlet+live+CD3+CD4+CFSEdim) and non- proliferating (gating: singlet+live+CD3+CD4+CFSEhi) compartment by flow cytometry based on CFSE-labeling of PBMCs after stimulus-free co-culture for 7 days. We performed RNA isolation and sequencing of these sorted cell subpopulations from 5 untreated RRMS patients in remission. The data compares differential expression of CD3+CD4+CFSEdim over CD3+CD4+CFSEhi? cells.