CXCL13 and neuromyelitis optica: There were no significant differences between serum CXCL13 levels in the 16 NMO patients using immunosuppressive agents (median, 170.28 pg/ml; range, 46.88–385.39) and the other eight NMO patients (median, 147.73 pg/ml; range, 73.10–398.22) (Figure 2a,b).