Statistically significant differences in the number of CD24 positive muscle fibers and satellite cells between sarcoglycanopathy and age-matched Becker muscular dystrophy patients

Object: The aim of this study was to reveal variations in the patterns of expression of the cell surface proteins in regenerating fibers and those in the number of satellite cells to gain an understanding of the pathological processes involved in sarcoglycanopathy. Methods: We have reported that there is a reduction of the beta-1 subunit of laminin, heparan sulfate proteoglycan (HSPG), and HCAM (CD44) in Japanese patients with sarcoglycanopathy. Here, we investigated immunohistocheniically the expression of the neural cell adhesion molecule (NCAM), which is a marker for human regenerating muscle and satellite cell, and CD24, which appears to be expressed in the early stages of the regeneration process. Patients: We investigated six Japanese patients with sarcoglycanopathy, and compared to age-matched Becker muscular dystrophy. Results: We found that the incidences of muscle fibers with increased NCAM were not statistically different between the two groups. However, the incidences of muscle fibers with increased CD24 and those of NCAM positive satellite cells were very low in sarcoglycanopathy and were statistically different between sarcoglycanopathy and age-matched Becker muscular dystrophies. Conclusion: The poor expression of CD24 and the fewer satellite cells in sarcoglycanopathy without significant difference in the number of total regenerating fibers suggest that a different regeneration process is involved in sarcoglycanopathy compared to that in other types of muscular dystrophy.(Interal Medicine 38: 412-415, 1999)