IGHG3 and myasthenia gravis: In AChR-MG, impaired regulatory T cells (Tregs and T follicular regulatory cells, Tfr), reduced regulatory B cells (Bregs), and diminished myeloid-derived suppressor cell (MDSC) function promote T follicular helper (Tfh) cell-driven germinal center activation and production of IgG1 and IgG3 antibodies [16].