A new technique, developed in the laboratories of the Foundation San Raffaele Biomedical Park, facilitates the process of regeneration of muscle tissue.

Stem cells, modified at the level of genes, could permit the recovery of tissue degenerated from Duchenne muscular dystrophy (Dmd), even when the disease is in an advanced stage. This is a further step towards developing a therapy, which is being developed for some years by researchers of the Foundation San Raffaele Biomedical Park of Castel Romano, coordinated by Giulio Cossu, University of Milan. The research, published in Nature Medicine, was conducted by Cesare Gargioli and Marcello Coletta, along with Fabrizio de Grandis and Stefano Cannata at the Roman Tor Vergata.

From previous studies and experiments on animal models it is known that mesangioblasti, stem cells normally associated with blood vessels, are able to spread easily and merge with and into the muscle tissue regenerating it (cell therapy). In advanced stages, however, this treatment had so far proven ineffective because of difficulties to penetrate between the muscle fibers. The degeneration, in fact, is accompanied by a process of inflammation followed by scarring tissue that impedes the provision of blood (and thus oxygen) to the muscles. Therefore, the muscle fibers are replaced with fatty tissue.

To overcome the obstacle, the researchers genetically modified cells derived from the tendons (fibroblasts) so as to make them express the protein metalloproteasi 9 (Mmp9), a molecule that can degrade collagen that accumulates between fibres degeneration.