Congenital muscular dystrophy (CMD) is a type of muscular dystrophy that is present at birth. CMD includes a number of autosomal recessive diseases of muscle weakness and possible joint deformities, present at birth and slowly progressing. Life expectancies for affected individuals vary, although some forms of CMD do not affect life span at all. At the moment, there is no cure for these conditions, and treatment usually involves physical therapy, surgery and use of a wheelchair.
One form of CMD, Ullrich congenital muscular dystrophy, is caused by a mutation in the COL6 group of genes, which code for the collagen VI protein subunits. Collagen VI is part of a group of proteins that are instrumental in maintaining the integrity of tissues, such as muscle. Ullrich CMD patients with mutations in the COL6 gene lack this vital protein. This shows for the first time that a possible therapy for Collagen VI CMD is to introduce stem cells making normal COL6 protein into COL6 CMD-affected muscles.
In the new study, researchers at Thomas Jefferson University found that stem cells derived from the adipose layer of foreskin -discarded after circumcision- of newborns could synthesise and secrete collagen VI. Furthermore, these stem cells seem to be better compared to stem cells derived from other, more traditional sources.
"While working in the Department of Dermatology, I had access to the skin specimens collected after newborn circumcision. My initial thought was that newborn skin should have plenty of stem cell precursors and that was the case. Another advantage, cells collected at an early age have higher regenerative potential than cells collected from adult donors." said leading author Olga Igoucheva.
The stem cells were first extracted and cultured, and then transplanted into mutant mice lacking the COL6A1 gene. The mice were injected with stem cells under physiological and pseudo-inflammatory conditions, mimicking severe Ullrich CMD. The stem cells were accepted by the mice and displayed long-term survival and secretion of the collagen VI protein missing in mutant mice.
"We believe that this research opens up new opportunities for replacing missing proteins that lead to COL6 CMD. Stem cells can be used as protein factories rather than the traditional approach of using stem cells to make new muscle cells. Using human adipose-derived stem cells - a readily available commodity - opens up a potential new treatment paradigm for CMD." said Olga Igoucheva.
The research was funded by Cure CMD, who support research into treatments, and a future cure, for CMD.
-Alexeev V., Arita M., Donahue A., Bonaldo P., Chu M.L. & Igoucheva O. (2014). Human adipose-derived stem cell transplantation as a potential therapy for collagen VI-related congenital muscular dystrophy, Stem Cell Research & Therapy, 5 (1) 21. DOI: 10.1186/scrt411