Two-dimensional gel electrophoresis in inclusion body myositis

Inclusion body myositis (IBM) is an acquired inflammatory myopathy in which a wide range of proteins is deposited within the cytoplasm of muscle fibres. To explore the possibility that this deposition occurs due to uncontrolled protein production arising from a defect at the nuclear level, we studied muscle samples from IBM and control subjects using two-dimensional gel electrophoresis. Twenty-seven gels from five controls and 24 gels from six patients with IBM were exhaustively compared using image analysis software and visual inspection. We found significant intra- and inter-subject variability in the number of protein spots on the gels. From 2272 to 4522 spots were found in different control gels, and from 2821 to 4153 spots in the IBM gels. No unique spots were identified in the IBM gels. When viewed with other work, the results of this study suggest that widespread, uncontrolled activation of genes is unlikely to be a component of the pathogenesis in IBM.