Cell Transplantation and “Stem Cell Therapy” in the Treatment of Myopathies: Many Promises in Mice, Few Realities in Humans
Figure 3
Potential neoformation of small myofibers after myoblast transplantation in a DMD patient. The figure shows serial cross-sections of a muscle biopsy done in the tibialis anterior of a 16-year-old DMD patient, corresponding to a site that was transplanted 1 month before with myoblasts proliferated in culture from a muscle biopsy performed in the deltoid of his father. The sections were stained with hematoxylin and eosin (a) and for the fluorescent immunodetection of dystrophin with MANEX50 (b). This antibody detects an epitope coded by the exon 50 of the dystrophin gene, which was the exon deleted in the patient, confirming that the dystrophin is from donor origin. There is an accumulation of small myofibers dispersed into an extrafascicular accumulation of the connective tissue ((a), between arrowheads). All of these small myofibers are donor-derived dystrophin+. We interpreted that this corresponds to myofiber neoformation due to the fusion of the implanted myoblasts among them. This was based on the fact that these focal accumulations of connective tissue with small myofibers were observed only in the cell-grafted sites, and that these small myofibers were small and entirely donor-derived dystrophin+. Some observations in nonhuman primates support this hypothesis. Scale bars = 50 μm.
