Louboutin J P, Navenot J M, Villanova M, Rouger K, Merlini L, Fardeau M
Laboratory of Cellular and Molecular Physiopathology and Pharmacology, CJF Inserm 96-01, Hopital GR Laënnec, Nantes, France.
Muscle Nerve. 1998 Jul;21(7):932-5. doi: 10.1002/(sici)1097-4598(199807)21:7<932::aid-mus11>3.0.co;2-s.
We have studied the expression of S-protein on the muscle from patients with X-linked vacuolated myopathy [characterized by the deposition of the complement C5b-9 membrane attack complex (MAC) over abnormal muscle fibers] and controls by immunocytochemistry and immunoblotting. No expression was detected on muscle from controls and patients with X-linked vacuolated myopathy. These findings suggest that S-protein does not render the MAC inactive in X-linked vacuolated myopathy. This situation may be due to the fact that the pathways of MAC activation and the expression of S-protein in X-linked vacuolated myopathy are different from the ones observed in ischemic and/or necrotic, or immune diseases. These results emphasize the role of the membrane complement regulatory proteins (i.e., CD59) in X-linked vacuolated myopathy.
