Immunolocalization of tenascin-C in human type II fiber atrophy.
Tenascin-C is a multifunctional extracellular matrix glycoprotein with stimulatory and anti-adhesive or inhibitory properties for axon growth. Its location and discontinuous expression are restricted in innervated muscle tissues. Tenascin-C accumulated interstitially among human denervated muscle fibers and close to normal-sized fibers. To expand our knowledge of the expression of tenascin-C in human neuromuscular disorders, we investigated immunohistologically 20 human muscle specimens with type II myofiber atrophy of children and adults. Tenascin-C immunoreactivity in adult type II atrophy was frequent, and accumulation in children was sparse and weak. In both groups, tenascin-C immunoreactivity was found: 1. Interstitially around normal-sized type II muscle fibers. 2. Around atrophic type II muscle fibers. 3. Around small-caliber myofibers with centrally located nuclei. These results indicate that tenascin-C immunoreactivity: (1) is detectable around early denervated and reinnervated muscle fibers and, therefore, (2) may reflect in part the molecularly ongoing process of denervation and reinnervation in human type II fiber atrophy.
Schoser
B G
BG
Department of Neurology, University Hospital Hamburg-Eppendorf, Hamburg, Germany.
Faissner
A
A
Goebel
H H
HH
D000328:Adult; D000368:Aged; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008297:Male; D008875:Middle Aged; D018656:Muscle Fibers, Fast-Twitch / Q000473:pathology*; D009133:Muscular Atrophy / Q000473:pathology*; D019063:Tenascin / Q000032:analysis*
D019063:Tenascin