Blood lymphocyte subpopulations show characteristic changes during ACTH therapy in acute exacerbations of multiple sclerosis.

The percentages of the various lymphocyte subpopulations in blood samples of 22 patients suffering from acute bouts of multiple sclerosis (MS) were determined by E rosette formation and peroxidase staining techniques, respectively, before and during ACTH therapy. In accordance with earlier reports, most of the subjects showed a normal increase of their plasma cortisol concentrations in an ACTH quick test, which was routinely performed before the beginning of therapy. We observed a significant transitory decrease of the absolute and relative T-cell proportions with a minimum around the tenth day of treatment, accompanied by inverse changes of the null-cell numbers. The concentrations of total white blood cells, total lymphocytes, B-cells, and monocytes did not change significantly. Our results are consistent with data reported in the literature on follow-up studies of lymphocyte subpopulations in patients with myasthenia gravis undergoing treatment with ACTH and corticosteroids, respectively. Recent experimental findings indicate that T-helper cell activity can be regulated by a negative feedback control mechanism. In consideration of these reports, we discuss the significance of changes in the distribution of lymphocyte subpopulations for the therapeutic action of ACTH and corticosteroids in MS.