Fig. 3

Oxidative phosphorylation protein deficiencies in Alpers’ syndrome patient astrocytes. (a) Quadruple immunofluorescence assay revealed decreased protein abundance of NDUFB8 (complex I subunit) and COXI (complex IV subunit) within GFAP + astrocytes in occipital cortex tissues from patients with Alpers’ syndrome relative to control astrocytes, despite increased porin signal (mitochondrial marker). Note astrocytes demonstrate weak immunoreactivity of all mitochondrial markers compared to adjacent neurons (arrow head). Scale bars = 10 μm. (b) Graphs demonstrate the percentage of GFAP + astrocytes with decreased mean optical intensity of NDUFB8 and COXI normalised to porin, relative to control astrocytes. Levels of deficiencies are based on standard deviation limits of control data: z-score < -2 = low expression; z-score < -3 = deficient; z-score < -4 = severely deficient [45]. N = 5 Controls, N = 5 SUDEP cases