Tissue engineering experts discuss orthopaedics applications

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Tissue engineering experts discuss orthopaedics applications

11 Apr 2005 Medical News Today

A future in which laboratory-grown organs and stimulated growth of

muscle, bones and nerves could play a major role in treating medical

conditions was revealed at a recent Tissue Engineering Symposium at

Wake Forest University Baptist Medical Center.

The symposium, sponsored by Wake Forest Baptist and the International

Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine,

was part of the society's annual conference. Tissue engineering

experts from Wake Forest Baptist, Children's Hospital of Pittsburgh,

Carnegie Mellon University, the University of Texas at Austin, as

well as Italy and Japan, discussed their latest work.

Tissue engineering, a term that was coined in 1986, describes the

science of replacing, repairing or regenerating organs or tissue. The

term is often used interchangeably with regenerative medicine.

In the field of orthopaedics, researchers described using growth

factors to regenerate bone, using new technologies to enhance the

healing of ligaments, efforts to produce tissue-engineered cartilage,

and the possibility of use stem cells derived from muscle to improve

bone healing. These advances could provide better treatments for

sports injuries, cleft palate and osteoporosis, the researchers said.

" The potential in orthopaedics is not only to manage devastating

congenital or traumatic problems but also to prevent or slow

degenerative processes in order to maintain the activity and function

of our aging population, " said G. Poehling, M.D., professor and

chairman of othopaedics at Wake Forest Baptist.

Atala M.D., director of the Wake Forest Institute of

Regenerative Medicine, said that laboratory-grown organs may one day

help alleviate the shortage of donated organs for transplantation.

Atala has developed bioengineered urethras, the tube through which

urine is excreted from the bladder, that have been successfully

implanted in humans. He has also created blood vessels, muscle,

bladders, wombs, and vaginas that have been successfully tested in

large animals and are close to being ready to test in humans.

Atala's team is working to use patients' own cells to grow more than

20 different tissue types. They harvest cells from humans and apply

growth factors, to cause the cells to multiply outside the body. It

can take years to develop and perfect these growth factors, which

cause a group of cells about one centimeter in size to multiply to

fill a football field in about 60 days. The cells are " seeded " on a

model, or scaffold, where they continue to grow. The next step is

implanting the model in the body, where the scaffold eventually

degrades as the new organ or tissue integrates with the body.

In addition to engineering tissues and organs, Atala and his team are

also working to identify new sources of stem cells. Because these

cells are unspecialized, they can acquire the structure and features

of other cell types, and some researchers believe they could be used

to replace defective insulin-producing cells in the pancreas, as well

as to treat Alzheimer's, liver, heart, muscular and vascular

diseases.

Nerem, Ph.D., director of the H. Petit Institute for

Bioengineering and Bioscience at the Georgia Institute of Technology

predicted that one day tissue engineering and regenerative medicine

will result in a revolution in the medical implant industry.

But Nerem and others who work in this emerging field said that while

the area is full of promise, there are still many challenges to face

before new therapies will be widely available.

" These technologies are expensive and for some of them, distribution

is a challenge, " said Atala.