The muscular dystrophies are characterized by progressive weakness and wasting of striated muscle and are caused by inherited or de novo gene mutation of sarcolemma-associated proteins or nuclear membrane–associated proteins. Patients suffering from muscular dystrophies can obtain a precise diagnosis of their underlying molecular defect, but no efficient treatment to prevent disability and death has been available. In the July 10 Sciencexpress, Maurilio Sampaolesi and colleagues from the Stem Cell Research Institute at San Raffaele Hospital show that that intraarterial delivery of mesoangioblasts can correct the molecular defect in a murine model of muscular dystrophy (Sciencexpress, DOI:10.1126/science.1082254, July 10, 2003).

Sampaolesi et al. injected [14C]thymidine-labeled wildtype mesoangioblasts into the right femoral artery of 1-month-old α-sarcoglycan (α-SG) null mice—a model for limb-girdle muscular dystrophy. They observed that this form of cell delivery was effective in restoring expression of α-SG protein and of the other members of the dystrophin-glycoprotein complex in the α-SG null mice. In addition, they showed that when mesoangioblasts isolated from juvenile dystrophic mice and transduced with a lentiviral vector expressing α-SG were injected into the femoral artery of dystrophic mice, they reconstituted skeletal muscle in a manner similar to that seen in wildtype cells.

"These data indicate that mesoangioblasts represent a promising approach to cell therapy of primary myopathies. In comparison with skeletal myoblasts, mesoangioblasts show the ability to cross the endothelium and migrate extensively in the tissue interstitium, where they are recruited by regenerating muscle fibers, thus reconstituting the dystrophin-glycoprotein complex," conclude the authors.