Lexington, Mass. (PRWEB) January 24, 2014
As published online today in Human Molecular Genetics, support from the FSH Society, a patient-driven nonprofit, has enabled people with facioscapulohumeral muscular dystrophy (FSHD) to donate muscle tissue, which scientists have succeeded in grafting into mice, providing a new tool for conquering this devastating muscle-wasting disease. Among the most common forms of muscular dystrophy, FSHD affects an estimated 500,000 people around the world.
Since the discovery of FSHD’s genetic mechanism in 2010, scientists have been forging ahead to find drugs and genetic therapies that could block this mechanism. But there remain major obstacles in the path to a treatment. One of the most significant roadblocks is the lack of a preclinical research model that can be used to study the disease in depth and to evaluate new therapies.
Building an FSHD model has proven to be a substantial challenge. The genetic mechanism of FSHD is extraordinarily complex, with components that do not exist in mice. To overcome this difficulty, a multi-institutional team led by Kathryn Wagner, MD, PhD, Director of the Center for Genetic Muscle Disorders at the Kennedy Krieger Institute and The Johns Hopkins School of Medicine decided to transplant human muscle into mice, grafting tissue taken surgically from the biceps of FSHD patients into the leg muscles in living mice.
The grafted muscles received a blood supply and nerve signals from the host mice, which were bred with defective immune systems to prevent rejection of the foreign tissue. The grafts survived for more than 40 weeks, during which time they regenerated. The grafted muscles could contract like normal muscle, and retained the cellular and genetic characteristics of muscle from a human with FSHD.
“Most potential novel therapies fail to successfully translate from animals to humans,” says Wagner. “Growing human tissues in animals (xenografts) has previously led to the successful development of therapies for multiple cancers and now, with this new muscle xenograft model, we are hopeful that new therapies for muscular dystrophy will emerge.”
The study’s authors thanked the FSH Society for its “invaluable” help recruiting FSHD patients to participate in the research. The disease is inherited, though it can be caused by a spontaneous mutation, and strikes young and old, both male and female. It melts away skeletal muscle, with symptoms usually noticeable by young adulthood. It is progressive, chronic and there is no cure or treatment. The name comes from the areas of the body where it often is first seen – the face, shoulders and upper arms – but it weakens muscles throughout the body. About one third of patients end up in a wheelchair.
Study co-authors came from the Kennedy Krieger Institute, Baltimore, Maryland; University of Massachusetts Medical School, Worcester, Massachusetts; Harvard Medical School, Boston, Massachusetts; University of Maryland School of Nursing, Baltimore; University of Maryland School of Medicine, Baltimore; and Children’s National Medical Center, Washington, D.C.
The research was supported by the National Institutes of Health (NIH) and the Muscular Dystrophy Association. This work was also made possible by the National Center for Research Resources (NCRR) a component of the NIH, and NIH Roadmap for Medical Research.
Reference: Yuanfan Zhang, Oliver D. King, Fedik Rahimov, Takako I. Jones, Christopher W. Ward, Jaclyn P. Kerr, Naili Liu, Charles P. Emerson, Jr., Louis M. Kunkel, Terence A. Partridge, Kathryn R. Wagner. Human skeletal muscle xenograft as a new preclinical model for muscle disorders. Human Molecular Genetics.