Stem cell therapy promises hope for muscular dystrophy victims

Nov 15 2006

Italian scientists, by using new stem cell therapy on dogs with muscular dystrophy, have improved the dogs condition to such an extent that the dogs were able to walk and even jump again.

Experts say the research is a significant breakthrough and a step closer to toward treating people with the disabling illness.

The scientists from the San Raffaele Scientific Institute in Milan saw improvements in two golden retrievers that were severely disabled by the disease, after transfusing a specific type of stem cell into the bloodstream of the dogs.

The study used stem cells taken from the affected dogs or other dogs, rather than from embryos.

For human use, the idea of using such "adult" stem cells from humans would avoid the controversial method of destroying human embryos to obtain stem cells.

Professor Giulio Cossu, who led the research says even though the treatment does not represent a cure, it does appear to ameliorate the condition and is a step towards finding a real cure.

After more tests on dogs, Cossu and his team hope to begin trials of the stem cell treatment in humans in a few years' time after more tests are done on dogs.

Duchenne muscular dystrophy, is a disease which occurs in about 1 in every 3,500 male births, and is caused by the absence of a protein called dystrophin that is involved in maintaining muscles.

It is a progressive illness that usually begins between 3-5 years old and by the age of 12 many sufferers are unable to walk and most die in their 20s because of weakness in their heart and lung muscles.

Although drugs can slow down the deterioration of the muscles and control the seizures, there is no therapy to stop or reverse the illness.

There are more than 20 types of muscular dystrophy, as well as other muscle disorders, but few treatment options.

Cossu and his team tested the treatment on dogs with a disease similar to Duchenne muscular dystrophy after earlier studies on transgenic mice.

They extracted cells called mesoangioblasts, which are programmed to develop into muscle cells, from small blood vessels in the sick dogs and after inserting a normal version of the mutated gene, they replaced the cells in vessels in the dogs' hind legs.

They also transfused stem cells taken from healthy dogs into sick dogs and gave them immune-suppressing drugs so they would not reject the donor cells.

After five monthly injections, muscle function was restored in varying degrees and dystrophin was produced in cells in the animals.

The cells helped strengthen muscle by fusing with regenerating muscle fibers and pumping out the missing protein in the dogs.

The dogs that received the donor cells showed more improvements in movement.

In theory, the stem cell treatment might also help other muscle dystrophies or even age-related muscle wasting.

Professor Cossu believes that a human treatment could be directed more at breathing muscles than it was in the dogs.

The study is published in the journal Nature.