Cell adhesion molecule N-CAM is expressed by denervated myofibres in Werdnig-Hoffman and Kugelberg-Welander type spinal muscular atrophies.
Immunocytochemical analysis utilising antibody to neural cell adhesion molecule (N-CAM) was carried out on skeletal muscle biopsies from patients with childhood spinal muscular atrophy. Children with both Werdnig-Hoffmann and Kugelberg-Welander disease showed positive N-CAM reactivity. There were however differences in the N-CAM expression profiles in these two sets of patients. All myofibres were positive for N-CAM in the Werdnig-Hoffmann patients. This included both the normal sized fibres and the atrophic fibres. In contrast only the atrophic fibres were positive in the Kugelberg-Welander patients. No reactivity was found associated with the large hypertrophic fibres. It is likely that in the Werdnig-Hoffmann patients the positive N-CAM reactivity reflects unstable innervation of myofibres that had been previously innervated. A similar mechanism may operate in the Kugelberg-Welander patients, but the innervation of the hypertrophic fibres is more stable as they are able to repress N-CAM expression. These results contrast with a lack of N-CAM expression found previously on muscle biopsies from adults with denervation disease.
Walsh
F S
FS
Moore
S E
SE
Lake
B D
BD
D000954:Antigens, Surface / Q000378:metabolism*; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules; D002648:Child; D005455:Fluorescent Antibody Technique; D006651:Histocytochemistry; D006801:Humans; D009132:Muscles / Q000294:innervation / Q000378:metabolism* / Q000473:pathology; D009133:Muscular Atrophy / Q000378:metabolism* / Q000473:pathology
D000954:Antigens, Surface; D015815:Cell Adhesion Molecules