Gene engineered stem cells heal rat spines -study

WASHINGTON (Reuters) – Genetically engineered stem cells
can help rats’ severed spinal cords grow back together,
according to a study published on Tuesday.

Rats given the treatment, using stem cells taken from rat
embryos, could move their legs again after their spines were
severed in the lab, said the researchers’ report in the Journal
of Neuroscience.

The scientists hope the approach, which generated a new
fatty cover for the spinal cord cells called the myelin sheath,
also could be shown to work in people.

The key is using the right stem cells and then stimulating
them correctly, said the researchers, who were led by Scott
Whittemore of the University of Louisville School of Medicine
in Kentucky.

“These findings suggest the possibility that
transplantation therapy using a subset of neural stem cells and
neurotrophic factors might improve functional recovery in human
spinal cord injury,” said Dr. Michael Selzer, a professor of
neurology at the University of Pennsylvania Medical Center in
Philadelphia.

Spinal cord injuries can be caused by accidents or
infections and affect 250,000 people a year in the United
States alone, costing $4 billion annually, according to the
National Institute of Neurological Disorders.

Whittemore’s team took specific cells from rat embryos
called glial restricted precursor cells — a kind of stem cell
or master cell that gives rise to nerve cells.

They genetically engineered these cells to do a little
extra work by producing a compound called a growth factor — in
this case, a new one called multineurotrophin. It was designed
to coax immature neural stem cells to mature and become
specialized cells called oligodendrocytes.

Oligodendrocytes help myelin grow onto nerve fibers, which
cannot grow or function without this fatty protective coating.

Two-thirds of the rats in the study regained some hind limb
movement, the researchers said.