LYMPHOCYTE SUBPOPULATION IN NEOPLASTIC AND NON-NEOPLASTIC THYMUS AND IN BLOOD OF PATIENTS WITH MYASTHENIA-GRAVIS

  • 1 January 1976
    • journal article
    • research article
    • Vol. 26  (1) , 118-123
Abstract
The lymphocyte subpopulations in the thymus and in the blood were investigated in 10 myasthenic patients who were thymectomized. Histologically, the thymuses tested comprised 3 cases of thymoma including 2 cases with malignant characteristics, 5 cases of hyperplastic thymus with lymph follicles and germinal centers, and 2 cases of persistent thymus without lymph follicles. Virtually all lymphoid cells in the 3 thymomas formed spontaneous rosettes with sheep red blood cells as did normal thymocytes from non-myasthenic patients. There was no significant proportion of immunoglobulin(Ig)-bearing lymphocytes. While the majority consisted of cells forming spontaneous rosettes with sheep red blood cells, there was a certain proportion (2-17%) of Ig-bearing lymphocytes in 4 of 5 hyperplastic thymuses, in 1 of 2 persistent thymuses, and in a residual atrophic thymus of a thymoma. The myasthenic patients tested were mostly normal (as compared with healthy individuals) in the proportion of rosette-forming lymphocytes and Ig-bearing lymphocytes in the blood collected immediately before and 1-3 mo. after thymectomy. The presence of Ig-bearing lymphocytes in the thymus was not necessarily related to the appearance of circulating antibody to striated muscle. The antibody to striated muscle was demonstrated in all myasthenic patients with thymoma.