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Stem Cells and Diseases
The Promise of Stem Cells
Studying stem cells will help us understand how they
transform into the dazzling array of specialized cells that make
us what we are. Some of the most serious medical conditions,
such as cancer and birth defects, are due to problems that occur
somewhere in this process. A better understanding of normal cell
development will allow us to understand and perhaps correct the
errors that cause these medical conditions.
Another potential application of stem cells is making cells
and tissues for medical therapies. Today, donated organs and
tissues are often used to replace those that are diseased or
destroyed. Unfortunately, the number of people needing a
transplant far exceeds the number of organs available for
transplantation. Pluripotent stem cells offer the possibility of
a renewable source of replacement cells and tissues to treat a
myriad of diseases, conditions, and disabilities including
Parkinson's disease, amyotrophic lateral sclerosis, spinal cord
injury, burns, heart disease, diabetes, and arthritis.
Clinical Trials for Stem Cell Therapies:
Human embryonic stem cells:
Scientists have been able to do experiments with human
embryonic stem cells (hESC) since 1998, when a group led by Dr.
James Thomson at the University of Wisconsin developed a
technique to isolate and grow the cells. Although hESCs are
thought to offer potential cures and therapies for many
devastating diseases, research using them is still in its basic
stages.
The NIH funded its first basic research study on hESCs in
2002. Since that time, biotechnology companies have built upon
those basic foundations to begin developing stem cell-based
human therapies. There are currently two active clinical trials
using cells derived from human embryonic stem cells, both being
conducted by a biotechnology company called ACT. The company has
laboratories in Marlborough, Massachusetts and corporate offices
in Santa Monica, California. ACT has begun enrolling patients
for Phase I (safety and tolerability) clinical trials of two
hESC-derived stem cell products:
- The
first ACT trial is testing the safety of hESC-derived
retinal cells to treat patients with an eye disease called
Stargardt's Macular Dystrophy (SMD).
-
- The
second ACT trial is testing the safety of hESC-derived
retinal cells to treat patients with
age-related macular degeneration.
In January, 2012, the investigators published a preliminary
report on the first two patients treated with hESC-derived
cells:
http://www.ncbi.nlm.nih.gov/pubmed/22281388. A
third patient was treated on April 20, 2012.
- A third clinical trial using hESC-derived cells was halted
on November 14, 2011. The trial was being conducted by a
biotechnology company called Geron, located in Menlo Park,
California. Four patients with recent spinal cord injuries had
been enrolled for its clinical trial of a hESC-derived
therapy. The trial was testing the safety of using
hESC-derived cells to achieve restoration of spinal cord
function. Oligodendrocyte progenitor cells derived from
hESCs were being injected directly into the lesion site of the
patient's injured spinal cord. On November 14, Geron announced
that it was discontinuing its stem cell programs to
concentrate on cancer programs.
-
Bone marrow stem cells:
Bone marrow contains blood-forming stem cells (hematopoietic
stem cells) that have been used for decades to treat blood
cancers and other blood disorders. Umbilical cord blood is
another source of hematopoietic stem cells that is being used in
treatment. You can see a list of diseases that may currently be
treated with hematopoietic stem cells at the website of the
National Marrow Donor Program. You may also search for
clinical trials testing "bone marrow stem cells" or "umbilical
cord blood" on the Clinical Trials.gov website.
Human spinal cord stem cells:
A biotechnology company called Neuralstem, with corporate
headquarters in Rockville, Maryland is conducting a
clinical trial testing the use of human spinal cord stem cells
to treat Amyotrophic Lateral Sclerosis (ALS), also known as Lou
Gehrig’s Disease. The company obtained FDA approval to
conduct a Phase I trial (safety and tolerability study), and
began enrolling patients in January 2010. 12 participants have
received lumbar transplants, and in March 2012, the second
participant received an injection in the cervial region.
Click here to learn details about this trial as listed on
the Clinical Trials.gov website.
Human mesenchymal stem cells:
Osiris Therapeutics (Columbia, Maryland) is conducting 3
different Phase 2 clinical trials with a product from adult
mesenchymal cells (called Prochymal). The three trials are for:
- protecting pancreatic beta islet cells in adults and
children with newly diagnosed
type 1 diabetes; in partnership with the Juvenile Diabetes
Research Foundation.
- repair of heart tissue following a heart attack, and
- the repair of lung tissue in patients with chronic
obstructive pulmonary disease (COPD).
Osiris is also conducting
Phase 3 testing of
Prochymal for acute graft versus host disease (GvHD) and
Crohn's disease.
Participating in Clinical Trials
Scientists are testing the abilities of many different types
of stem cells to treat certain diseases. You can search for
clinical trials using stem cells (or other methods) to treat a
specific disease at
ClinicalTrials.gov.
Could stem cells someday
help treat paralysis?Thursday, October 21, 2010Tags:healthbeat,
sylvia perez
Comment NowEmailPrintReport a typo
Sylvia Perez
More: Bio, News Team October 21, 2010 (CHICAGO) (WLS) -- In a
landmark trial, researchers have begun using embryonic stem
cells to treat a paralyzed patient.
The stem cells have been at the root of hope and controversy for
years.
There has been little hope that a severely damaged spinal cord
can be fixed. For patients such as actor Christopher Reeve, a
cure did not come in time.
Researchers at a small hospital in Atlanta, Georgia have
injected the first patient with embryonic stem cells.
The next patient might receive the experimental treatment right
here in Chicago.
Almost one year ago, Kankakee County Sheriff's Deputy David
Stukenborg's life was shattered, along with his spine.
"Catastrophic blow out," said Stukenborg, describing the auto
accident that paralyzed him. "You could hear the tire explode,
and the car flipped multiple times."
Stukenborg was on his way to a 911 call when his tire blew. The
call turned out to be a prank.
"I broke C5, shattered C6, and broke C7," said Stukenborg,
referring to the vertebrae involved in his injury.
With the help of a robot at the Rehabilitation Institute of
Chicago, Stukenborg is working to regain some movement.
He has an incomplete spinal cord injury, which means his cord
was not severed.
Researchers hope to enroll patients with injuries like
Stukenborg's in a landmark trial. The ultimate goal is to see if
embryonic stem cells can reverse damage. The first phase is to
determine if the procedure is safe.
Northwestern Medicine in Chicago will play a role
"This is first and foremost a safety study: to prove that it can
safely be done in humans," said Northwestern Medicine
neurosurgeon Dr. Richard Fessler.
For years, scientists have been holding out hope that stem cells
could repair damaged spinal cords by helping to regenerate
damaged nerves.
The cells are obtained from human embryos no longer needed in
in-vitro fertilization procedures.
Extracting the cells destroys the embryo, which is the biggest
controversy. Critics say it is the destruction of human life and
should not be supported with federal research dollars.
Geron Corporation is the first to get federal approval to use
embryonic stem cells to treat people.
Laboratory studies have shown that animals with limited use of
their hind legs were able to walk again within weeks of being
injected.
"The biggest misconception probably is that it's going to be a
magic bullet, that we are going to do one experiment, we're
going to cure paralysis, and that everything will be wonderful,"
said Fessler. "That's not the case."
Patients must meet very specific criteria. The injury has to be
located in the thoracic spine between T-3 and T-10. The cord can
not be severed, and the injury must be recent, happening within
the last 11 days.
Therefore, as unnerving as it sounds, the next possible
participant in the trial probably has not been injured yet.
Even though this phase is just to measure safety, doctors will
still look for signs of unusual improvement.
"To try to differentiate what is natural recovery and what is
coming from this intervention," said RIC rehabilitation
physician Dr. David Chen, describing the goal of the process.
Stukenborg does not qualify for this clinical trial, but he says
it offers hope for anyone with paralysis.
"Until you have been in a position that's similar to mine, you
can't really put a value on it," said Stukenborg. "It's just
great."
Up to 10 patients with spinal cord injuries will be enrolled in
the study.
As of now, Northwestern does not have a patient for the study,
but even though this research is underway, the national debate
is far from over.
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