T cell response to myelin basic protein before and after treatment with interferon beta in multiple sclerosis.

Studies on the in vivo effects of interferon-beta (IFNbeta) therapy on autoreactive T cells have never been carried out in multiple sclerosis (MS). We investigated the T cell response to myelin basic protein (MBP), before and after IFN-beta therapy, raising MBP-specific T cell lines (TCL) from the peripheral blood of six MS patients with a satisfactory response to the treatment. IFNbeta did not affect the relative frequency and epitope specificity of the TCL. After IFNbeta therapy, the production of interleukin-4 was decreased in MBP-stimulated TCL while the secretion of interferon-gamma was increased in unstimulated TCL. Interleukin-10 and tumor necrosis factor-alpha did not show significant variations. This finding supports recent suggestions about the complexity of the T helper 1/T helper 2 paradigm in MS and other organ-specific autoimmune diseases. In fact, the beneficial effects of IFNbeta do not exclude an immunostimulatory action that may involve potentially autoreactive T cells. This has implications for future treatment options, including combination therapies.