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Burn Research without Animals
By Steven RaglandSevere burns pose a difficult medical challenge. Treatments are
limited for patients with extensive third-degree burns, and, even in the best of
circumstances, long hospital stays are the rule.
Research scientists Charles W. Hewitt, Ph.D., Edward Doolin, M.D., and colleagues at
the Robert Wood Johnson Medical School/Cooper Health System in Camden, New Jersey, are
hoping to change that. Working with both cloned cells and bioengineered tissues, Drs.
Hewitt and Doolin have created living human skin to serve as an experimental model for
burn research. Employing space-age technology, Dr. Hewitts laboratory grows skin in
a micro-gravity environment and uses it to study burns, immune rejection, and other
related issues. This human-based model not only replaces the use of animals, but can be
far superior.
As Dr. Hewitt explains, One advantage is that you can engineer these tissues any
way you want, so they actually come out human. A real advantage over animals is that you
can use human reagentsthose chemicals, probes, and therapies that are used on an
actual burn patientand get immediately relevant results.
As Director of Surgical Research, Dr. Hewitt is investigating mechanisms of how skin is
injured, sometimes in combination with infection or reduced immunity, and how transplanted
skin rejects.
Having lost a major portion of their skin, burn patients are vulnerable to bacteria,
viruses, and fungi. To restore their lost protection, doctors must remove a portion of
what little healthy skin the patient has left and expand itstretching the skin to
cover up to ten times its original area. Then, that skin must be grafted onto the patient,
allowed to grow, and then removed again to be stretched and re-grafted, and so forth. The
process is traumatic and, in the meantime, the remainder of their body not covered with
their own skin must be protected. A few optionsfrom donated human skin from cadavers
to commercial skin culturesexist, but their effectiveness may be limited. The
patients body can recognize them as foreign and ultimately reject the skin, just as
a kidney or heart recipient might reject a transplanted organ.
Using bioengineered human skin, Dr. Hewitt is able to study this rejection process in
an actual human model. His research is aimed at developing better methods to counter
immune rejection and, ultimately, new models for studying diseases.
Theoretically, if skin can be bioengineered, so can organs such as livers and kidneys,
reducing complications related to organ rejection. Ideally, a kidney, for example, could
be bioengineered from tissue taken from the patients own failing kidney, thus
creating a replacement organ that is genetically identical to the one being replaced.
Dr. Doolin, as Director of Pediatric Surgical Research, sees applications to help
correct birth defects. In some situations, reconstruction of organs damaged by a
birth defect is stalemated by inadequate tissue quantities or inadequate organs, he
explains. One of the things that we view as a future application of this work is to
be able to use a sample of a patients tissue to construct a new organ that can be
transplanted.
Dr. Hewitt emphasizes that his research is just a first step toward achieving such
success. However, it is a step being pursued in a way that clearly relates to human
health, without relying on animal experimentsan example of research done right. |