Figure 3.

Formation of C5b-9 complexes is associated with cell lysis and glial fibrillary acidic protein (GFAP) expression loss by a little number of astrocytes. (A) 11% of astrocytes is lysed in the presence of neuromyelitis optica spectrum disorder (NMOSD) anti-aquaporin-4 (AQP4) Ab-positive serum (left panel). Cell lysis expressed as a percentage of the change of lactate dehydrogenase (LDH) concentration normalized to positive and negative controls according to formula presented in [(A), upper right panel]. (B) Double-staining of astrocytes with C5b-9 and GFAP. Incubation of astrocytes with anti-AQP4 Ab-positive serum from NMOSD patients, opposite to multiple sclerosis (MS) and healthy control, activates C5b-9 complex formation (green arrows) accompanied by reduced GFAP expression (red arrows). (C) Confocal microscopy analysis confirms C5b-9 complex formation on the cell surface of astrocytes which characterized GFAP low expression.