At baseline, there were noticeable differences in the serum levels of IL-6 (21.5 pg/mL vs 5.6 pg/mL, p < 0.001), IL-17 (16.5 pg/mL vs 3.8 pg/mL, p < 0.001), and IL-21 (43.9 pg/mL vs 4.4 pg/mL, p < 0.001) between MG patients and HCs (Figures 6A, B). Here, IL21 is linked to myasthenia gravis.