The low EOMES/TBX21 molecular phenotype in multiple sclerosis reflects CD56Â + cell dysregulation and is affected by immunomodulatory therapies

- Expression of EOMES and TBX21 is low in blood from MS patients, and longitudinally stable.
- EOMES-TBX21 (“ET”) molecular phenotype is heritable and affected by MS therapies.
- A subset of immune cells in the blood is tagged by expression of EOMES and TBX21 in MS and controls.
- ET phenotype may be useful as a biomarker of clinical response to MS therapies.

Multiple Sclerosis (MS) is an autoimmune disease treated by therapies targeting peripheral blood cells. We previously identified that expression of two MS-risk genes, the transcription factors EOMES and TBX21 (ET), was low in blood from MS and stable over time. Here we replicated the low ET expression in a new MS cohort (p < 0.0007 for EOMES, p < 0.028 for TBX21) and demonstrate longitudinal stability (p < 10− 4) and high heritability (h2 = 0.48 for EOMES) for this molecular phenotype. Genes whose expression correlated with ET, especially those controlling cell migration, further defined the phenotype. CD56 + cells and other subsets expressed lower levels of Eomes or T-bet protein and/or were under-represented in MS. EOMES and TBX21 risk SNP genotypes, and serum EBNA-1 titres were not correlated with ET expression, but HLA-DRB1*1501 genotype was. ET expression was normalised to healthy control levels with natalizumab, and was highly variable for glatiramer acetate, fingolimod, interferon-beta, dimethyl fumarate.