CD4⁺ FoxP3⁺ T regulatory cell subsets in myasthenia gravis patients

Although myasthenia gravis (MG) is a classic autoantibody-mediated disease, T cells are centrally involved in its pathogenesis. In recent years a number of studies have analyzed the role of CD4⁺ FoxP3⁺ regulatory T cells (T_reg) in the disease with contradictory results. Here, the generation of T_reg was significantly reduced in thymoma as compared to thymic hyperplasia and normal thymus tissue (p=0.0002). In the peripheral blood, T_reg subsets classified according to CD49d, HELIOS and CD45RA expression changed after thymectomy and in the long-term course of immunosuppression. Compared to healthy volunteers the frequency of CD45RA⁺FoxP3^low T_reg was reduced in MG patients in general (p=0.037) and in particular in patients without immunosuppression (p=0.036). In our study, thymectomy and immunosuppressive treatment were associated with changes in T_reg subpopulations. The reduced frequency of CD45RA⁺FoxP3^low T_reg we observed in MG patients might play a role in MG pathogenesis.