The effect of ACTH treatment on lymphocyte subpopulations in patients with myasthenia gravis.

Blood lymphocytes were collected before, at various times during treatment and after treatment with ACTH in patients with myasthenia gravis. The relative proportions of thymus-derived (T cells) and bursa-derived (B cells) lymphocytes were determined. Eight of nine patients had a relative increase in B cells, whereas T cells showed a relative decrease. Myasthenic symptoms in these eight patients also were relieved. One patient who was not thymectomized showed virtually no relief in symptoms nor any changes in the relative T and B cell proportions or numbers, indicating a close association between the disease and the thymus-derived immune system.