Evaluation of T cell subsets in myasthenia gravis using anti-T cell monoclonal antibodies.

Functional T cell subsets have been evaluated in the peripheral blood of patients with myasthenia gravis using monoclonal anti-T cell antibodies and a suppressor cell assay based on the suppression of the mixed-lymphocyte reaction by concanavalin A-activated lymphocytes. A significant decline of suppressor cells was found in a large proportion of patients, both by direct count using the anti-suppressor-cytotoxic T cell antibody (OKT8) and by the suppressor assay. Patients also showed an increase in immature T cells defined by their simultaneous reaction with the anti-helper cell (OKT4) and anti-suppressor cell (OKT8) antibody. Thymectomy tended to enhance the deficit in suppressor cells, and to induce the disappearance of double-labelled cells.