Phenotypic characterization of autoreactive T cells in multiple sclerosis.

MS has been hypothesized to result from autoreactive T cell responses against myelin antigens. In this report, we examined myelin-specific CD8 and CD4 T cells for two markers differentially expressed on naïve, memory and chronically stimulated T cells, CD28 and CD57. We observed differential expression on CD8 T cells in response to myelin antigens, but not in response to the recall antigen mumps. We demonstrate these cells display reduced proliferation and this may explain why therapies that limit the proliferation of T cells have had little effect on the course of MS, particularly later in the course of the disease.