Abnormalities in the expression of β–spectrin in duchenne muscular dystrophy

We studied (β-spectrin using an immunologic probe in muscle samples from patients with Duchenne muscular dystrophy (DMD), Becker muscular dystrophy (BMD), other disease controls, and normal controls. By immunohistochemistry in DMD samples, β-spectrin showed reduced or interrupted staining of the entire cell surface or only patches of bright staining at the cell periphery. There were also alterations of β-spectrin immunostain in fibers that were not degenerating or regenerating. By immunoblotting, the amount of β-spectrin in muscle was reduced and varied from 52% to 78% of the normal controls. We found normal values of β-spectrin in BMD and disease controls. These observations indicate that the expression of β-spectrin in DMD is abnormal and that β-spectrin immunolabeling is not a good marker for monitoring membrane integrity in DMD muscle.