IFNß exerts its activity through the interaction with IFNAR, through activation of the JAK/STAT pathway. We analyzed the changes in IFNAR1, IFNAR2, STAT1, STAT2, Tyk2, JAK1, IRF9 and MxA gene expressions after prolonged IFNß treatment, in isolated mononuclear-cell subpopulations from MS patients, by real time PCR. The effect of IFNß on gene expression differed depending on the subpopulation assessed. The data suggest that CD8+ T cells are the most influenced by prolonged IFNß therapy as IFNAR2, Tyk2, IRF9 and Jak1 expressions were decreased, whereas MxA expression was increased in these cells
