Characterization of naïve, memory and effector T cells in progressive multiple sclerosis.

We characterized naïve, central memory (CM), effector memory (EM) and terminally differentiated effector memory (TEMRA) CD4 and CD8 T cells and their expression of CD49d and CD26 in peripheral blood in patients with multiple sclerosis (MS) and healthy controls. CD26 CD28 CD4 TEMRA T cells were increased in all subtypes of MS, and CD26 CD28 CD8 TEMRA T cells were increased in relapsing-remitting and secondary progressive MS. Conversely, in progressive MS, CD49d CM T cells were decreased and natalizumab increased the circulating number of all six subsets but reduced the frequency of most subsets expressing CD49d and CD26.