Stem cell injections fight muscular dystrophy in dogs: study in journal Nature

[Guest guest]

I know this is MD and not CMT, but a good read.

Wed Nov 15, 2:17 PM

By Malcolm Ritter

NEW YORK (AP) - In promising new research, stem cells worked

remarkably well at easing symptoms of muscular dystrophy in dogs, an

experiment that experts call a significant step toward treating people.

" It's a great breakthrough for all of us working on stem cells for

muscular dystrophy, " said researcher ny Huard of the University of

Pittsburgh, who wasn't involved in the work.

Sharon Hesterlee, vice-president of translational research at the

Muscular Dystrophy Association, called the result one of the most

exciting she's seen in her eight years with the organization. Her

group helped pay for the work.

She stressed that it's not yet clear whether such a treatment would

work in people, but said she had " cautious optimism " about it.

Two dogs that were severely disabled by the disease were able to walk

faster and even jump after the treatments.

The study was published online Wednesday by the journal Nature. It

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.

The Nature paper focuses on Duchenne muscular dystrophy, a

muscle-wasting genetic disorder that occurs in about one in every

3,500 male births. It's the most severe and most common childhood form

of muscular dystrophy and the best-known. In theory, the stem cell

treatment might also help other muscle dystrophies or even age-related

muscle wasting, Hesterlee said.

Children with the disorder have trouble walking as early as preschool,

and nearly all of them lose their ability to walk between ages seven

and 12. Typically, they die in their 20s because of weakness in their

heart and lung muscles. There is no known cure.

The dog study was done by Giulio Cossu, director of the stem cell

institute at the San Raffaele Scientific Institute in Milan, Italy,

with colleagues there and elsewhere.

" We do not know whether this will work in patients, " Cossu said in a

telephone interview. He said he hopes to start a small experiment in

children in the next year or two.

The scientists worked with golden retrievers that suffer a crippling

form of dystrophy very much like the human one. Researchers studied

the effect of repeated injections into the bloodstream of a kind of

stem cell extracted from blood vessel walls.

The best results appeared when the cells were taken from healthy dogs.

But Cossu said scientists should pursue the possibility of genetically

manipulating a patient's own cells and using them instead. That way,

patients wouldn't have to undergo lifelong treatment to avoid

rejection of donated cells.

In one of several experiments, three dogs that had not yet shown

impairment in walking were injected five times, a month apart, with

cells taken from other dogs.

One dog completely avoided symptoms and continued to walk well even

five months after both the injections and the anti-rejection therapy

were stopped.

A second dog also did well initially but died suddenly of a heart

problem after just two months on the treatment. It's not clear whether

the problem had anything to do with the treatment, or whether the

initial good result would have continued, Cossu said.

The third dog showed partial protection, being able to walk and even

run with a limp, but then progressively lost walking ability within a

few days after the anti-rejection treatment was stopped.

The researchers also treated two dogs that were severely impaired by

the disease. Both gained the ability to move much faster and to jump,

and one was even able to run, although neither could use the hind legs

normally.

One of these dogs rapidly lost walking ability when the anti-rejection

treatment was stopped, but the other continued to walk well for five

months until succumbing to pneumonia. That's a common fate for dogs

with the genetic condition because of weakness in breathing muscles.

Cossu said he believed that a human treatment could be directed more

at breathing muscles than it was in the dogs.

The cells helped strengthen muscle by fusing with regenerating muscle

fibres and pumping out a protein that's missing in dogs with the disease.