B and T lymphocytes in man. III. B, t, and "null" lymphocytes in multiple sclerosis.

T, B, and "null" lymphocytes were determined in peripheral blood obtained from 24 control subjects and 15 multiple sclerosis patients. The total number of lymphocytes and T lymphocytes were reduced significantly in multiple sclerosis patients as compared with those of controls. Although the percentage of B lymphocytes increased in these patients, the absolute number of B lymphocytes was similar to controls. The mitotic response of lymphocytes from multiple sclerosis patients to phytohemagglutinin and pokeweed mitogen in 7-day-old cultures was decreased as compared with that of controls.