FASLG and Guillain-Barre syndrome: Serum sFas (237.5 pg/mL vs. 159.5 pg/mL; P < 0.0001) and sFasL (225.1 pg/mL vs. 183.4 pg/mL; P = 0.0069) were elevated in patients with GBS compared to healthy controls, and among patients with high serum sFas was associated with severe GBS (P = 0.0406).