TNFRSF17 and myasthenia gravis: Given that MIF is a key driver of immunopathogenesis in rheumatic disorders (Kang and Bucala, 2019), and soluble BCMA (sBCMA) is a widely used surrogate marker for PB/PCs that is detectable in circulation (Mikkilineni and Kochenderfer, 2021), we measured the serum levels of MIF and sBCMA in an independent cohort of MG (n = 47), and age- and sex-matched controls (n = 47) using ELISA (Fig. 3E).