TP53 and neuromyelitis optica: In a validation experiment performed using rt-QPCR, we found that the expression level of tp53 is significantly increased in astrocytes cultured with seropositive NMO sera compared to sera of HCs (1.6 ± 0.6 RQ and 0.64 ± 0.4 RQ, respectively, p < 0.0001, Figure 3b).