미요시근병증에서 Dysferlin의 면역세포화학검사와 Western Blot의 분석

Abstract

Background: Recent genetic analyses have shown that Miyoshi myopathy (MM) is caused by a mutation in the DYSF, which induces the dysfunction of dysferlin. We identified the deficiency of dysferlin by immunohistochemistry and Western blot in four patients with clinically diagnosed MM, and investigated the clinical and pathological characteristics of MM. Methods: A muscle biopsy was performed in four patients who were diagnosed with MM by clinical and electrophysiological study. Immunostaining of muscle specimens for dyferlin, dystrophin, α, β, γ, δ-sarcoglycan, β-dystroglycan, and caveolin-3 were performed in all four patients. We analyzed the quantitative analysis for dysferlin by Western blot in three of four patients. Results: All four patients showed clinical onset during adolescence or early adulthood (15-26 year old), a slowly progressive course, and a relatively high serum creatine kinase level (2240-6400 IU/L). Routine pathological studies showed non-specific myopathic changes. On immunocytochemistry, there was negative immunoreacticity for dysferlin on muscle specimens in all patients. The immunoreactivities for dystrophin, α, β, γ, δ-sarcoglycan, β-dystroglycan, and caveolin-3 were normal. On Western blotting, complete loss of dysferlin was noted in all three patients with MM Conclusions: Identification of isolated deficiency of dysferlin on immunocytochemistry or Western blot is important for the confirmative diagnosis of MM.