Characterization of circulating gamma-delta T cells in relapsing vs remission multiple sclerosis.

We characterized circulating gamma-delta T cells in relapsing-remitting multiple sclerosis (RRMS) patients, during remission and relapse phases. In relapse, we observed a decrease of circulating CCR5 γδ T cell subset, together with a decrease in EOMES and granzyme B mRNA expression in γδ T cells, suggesting a reduction of the cytotoxic potential of this subset. Moreover, we also found a higher frequency of IFNγ γδ T cells, which may indicate that these cells are assuming a more regulatory function associated to a Th1 profile. These results suggest a specific release from the periphery of a particular γδ T cell subset, expressing CCR5 and belonging to an effector compartment, supporting the idea that γδ T cells could play a role in MS relapse.