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Cutting Edge
Biotechnology Advances
Imagine a time when treatment for RA is specially
designed for each patient… or an imaging or blood test can detect early signs
of cartilage or bone damage before disease symptoms occur so further damage can
be prevented… or those who already have significant joint damage are able to
get a cartilage transplant using tissue that had been engineered in the
laboratory, instead of having to resort to surgery. Sound like pipe dreams? Not
so, say several conference presenters.
Paving the Way for Patient-specific
Therapy
A therapy that selectively targets the specific proteins that provoke the
abnormal immune response in RA would be safer and more effective than
traditional immunosuppressive drugs. Previously, scientists have been
unable to determine which proteins are attacked in RA. However, as described in
presentations by Stanford researchers, Paul J. Utz, MD and Bill
Robinson, MD, PhD, significant progress has been made towards identifying
some of the culprit proteins. The investigators utilized a new technology called
"microarrays," which consist of glass slides dotted by a robotic
device with over 2,300 proteins and other molecules that could be attacked in
arthritis and related conditions. Then they applied blood taken from patients
with RA, osteoarthritis, reactive arthritis and lupus and analyzed the results
to see which molecules were attacked more often in RA as compared to the other
diseases. In a recently published study, these researchers have shown in mice
with a disease that resembles multiple sclerosis that this technology can be
used to develop a specialized vaccine that successfully turned off the immune
response. Read
more...
What's the relevance to people with
arthritis? Microarray technology may soon be able to direct the design
of patient-specific treatments, which would target just those proteins that
cause tissue damage, or perhaps even a specific vaccine for diseases that would
prevent or even cure arthritis.
Early Detection and Monitoring of OA
By the time that osteoarthritis (OA) is diagnosed, pain and irreparable
cartilage damage are often already present. However, much progress is being made
in developing efficient methods for detecting early changes in the joint and for
monitoring the progression of the disease. For instance, Mark Markel, DVM,
PhD and his colleagues at the University of Wisconsin in Madison are using
an animal model of OA in which dogs develop arthritis of the hip to study the
value of two antibody tests. Developed to detect cartilage breakdown products,
these antibodies were found to be good tools to predict the development of OA in
these animals. Use of markers such as these to predict the progression of OA in
its early stages in humans might help guide preventative measures and options
for therapies.
Using another approach, Peter Hardy, PhD, of the University of Kentucky,
has been following patients with varying degrees of OA and comparing data
obtained from MRIs (magnetic resonance imaging) to X-ray data. The MRIs map the
thickness of the cartilage as well as the narrowing of the joints as the
arthritis progresses. This appears to be a more sensitive tool than X-rays for
evaluating the progression of joint damage in OA and the effectiveness of
different therapies.
What's the relevance to people with
arthritis? New biomarker and imaging tests are providing a more
sensitive picture of how OA progresses. Eventually, they will allow doctors to
detect early signs of OA so that further damage can be prevented. Such tools
will also aid in the discovery and testing of new therapies.
New Cartilage for Damaged Joints
An exciting area in biotechnology is "tissue engineering," using
live cells to rebuild damaged tissue. It is difficult to grow high-quality
cartilage that maintains the smooth, shock-absorbing function of natural
cartilage. Jennifer Elisseeff, PhD at Johns Hopkins University and her
colleagues have determined that there are different layers or zones within
normal cartilage and that cartilage cells have different biologic properties
depending on which zone they are located in. She reported data that showed that
they could obtain and grow cartilage from the different zones, maintaining the
unique properties of the cartilage cells from each zone.
Similarly, Jean F. Welter, MD, PhD, at Case Western Reserve University,
reported progress in his work on growing cartilage cells in the laboratory. His
laboratory is using undeveloped "stem cells" taken from the bone
marrow that are applied in different ways to a sponge-type scaffold which holds
them together while they develop into cartilage tissue. The cartilage tissue is
grown within a special device called a bioreactor, which allows for Dr. Welter's
group to continuously monitor and determine the optimal set of conditions for
successfully engineering high-quality cartilage.
What's the relevance to people with arthritis?
If
successful, these studies will provide another approach to repair cartilage
damaged by OA and could form the basis for the development of a new generation
of treatments that provide an alternative to joint replacement surgery for those
with severe joint damage.
 
Research Update is compiled by
Michele Boutaugh, BSN, MPH, Medical and Scientific Affairs Department,
National Office.
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