CD4(+)CD45RO(+)CD49d(high) cells are involved in the pathogenesis of relapsing-remitting multiple sclerosis

In the animal model of multiple sclerosis, experimental autoimmune encephal omyelitis, encephalitogenic T cells differ from the non-encephalitogenic on es in their expression of CD49d. The disease-inducing CD49d(high) and not t he CD49d(low) cells enter the brain parenchyma. In this context, we charact erized CD4(+)(CD45RO(+))CD49d(high) cells in relapsing-remitting multiple s clerosis (RR-MS) patients. These cells, showing characteristics of activate d cells able to produce pro-inflammatory cytokines, were found to be increa sed in peripheral blood during relapses and present in high numbers in cere brospinal fluid. These results suggest that the CD4(+)CD45RO(+)CD49d(high) subpopulation in RR-MS patients includes autoreactive cells and may be targ et for immunotherapy. (C) 2000 Elsevier Science BN. All rights reserved.