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News from RedOrbit
23 Sept, 2006
Stem Cell
Clinical Trial to Treat Children
By Betsy Mason, Contra Costa Times,
Walnut Creek, Calif.
Sep. 23--The first clinical trial to transplant stem cells to treat
a brain disease is set to get under way this year.
The treatment involves injecting fetal brain stem cells into the
brains of children with the devastating genetic disorder known as
Batten disease, which usually results in death before the
age of 12. The stem cells that will be used in the trial are
produced by Palo Alto-based StemCells Inc.
"It is our hope and the hope of many others that this clinical trial
will provide insight into a potential treatment option for this
tragic disease," trial leader Robert Steiner said during a telephone
news conference Friday. Steiner is with Oregon Health & Science
University in Portland where the treatment will take place.
Previous trials, such as those for Parkinson's disease and spinal
cord injuries, used more mature brain cells that were already on
their way to becoming a specific type of cell, such as a neuron.
Whereas brain stem cells have not yet taken the first steps toward
becoming a specific type of brain cell and therefore have the
potential to become many different types of cells.
"It's the first trial that plans to use actual stem cells rather
than their differentiated products," said Arnold Kriegstein,
director of the Institute for Stem Cell and Tissue Biology at UC San
Francisco, which is not involved with the trial.
The StemCells Inc. cells to be used in the trial are not embryonic
stem cells, which come from embryos just a few days old. Instead,
these come from fetal brain tissue, acquired with the mother's
consent and are considered adult stem cells.
"These cells are not genetically modified in any way, and they are
not grown on any animal feeder cells," said Alan Jacobs of StemCells
Inc.
Some other stem cell lines have been grown on mouse feeder cells
which could make them unusable for human transplantation.
The company is looking into the potential for their brain stem cells
to be used to treat other brain diseases and spinal cord injuries,
Jacobs said.
In the current trial, six children between the ages of 2 and 12
suffering from Batten disease will be injected with the brain stem
cells.
Batten disease is extremely rare, striking just one in 100,000
children, and is invariably fatal. People with the disease are
missing enzymes that clear certain fatty substances from brain cells.
A buildup of these fats damages different parts of the brain and
leads to seizures, blindness, loss of the ability to walk and speak
and eventually death.
"I've seen first-hand the devastation of these diseases." said
Steiner. "They eventually become bed-ridden and debilitated, and
death is inexorable."
The children in the trial will have stem cells injected by needles
directly into several different areas on both sides of the brain
through holes drilled in the skull. A computerized map of each
child's brain will help the surgeon guide the needles to the right
spot.
"The hope is that these cells will work as delivery vehicles,"
Kriegstein said. "What you want is a cell that will disperse and
distribute itself through the brain and then sit there pumping out
the enzyme."
The first participant will be treated sometime before the end of the
year and will be monitored for at least a month to assess the safety
of the procedure before the next patient is treated. All of the
patients will be closely monitored for a year after their treatment
and then followed for several years beyond that.
"We think this is a very important first step in a ground-breaking
process to bring this kind of technology to the forefront in order
to help patients," said Nathan Selden of OHSU, the surgeon who will
do the injections.
While they do hope the stem cells will help these children, the
doctors emphasized that the primary goal of the study is to evaluate
the safety of the treatment.
In experiments in mice that were missing the same enzymes as the
Batten disease patients, the human brain stem cells produced the
missing enzyme and the mice lived longer than those that didn't get
human stem cells.
"The level of the enzyme climbs following transplantation" of the
stem cells, Jacobs said. "In concert with this, there is a reduction
in the amount of abnormal storage material that accumulates in the
brains."
It is very difficult to predict if the cells will do the same in a
human brain, Kriegstein said. Mouse brains are much smaller, and the
cells might not spread as well in human children.
"That's a much larger territory to cover," he said.
There is also the fear that the stem cells' ability to multiply into
more stem cells could cause them to grow tumors.
Kriegstein is skeptical that the children in this trial will benefit
significantly from the treatment, and stem cell researchers all over
the world will be watching to see if injecting these stem cells is
safe.
"We'll hope to learn from this trial quite a lot," Kriegstein said.
The scientists running the trial said they are not likely to divulge
any information about the trial until after it is over because of
its highly sensitive nature and to protect the privacy of the
children and families involved.
Reach Betsy Mason at
bmason@cctimes.com or 925-847-2158.
http://www.redorbit.com/news/health/667600/stem_cell_clinical_trial_to_
treat_children/index.html?source=r_health
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