University of Utah bioengineers made tiny, living Olympic Rings from nerve cells to demonstrate technology that someday might help repair spinal cord injuries from accidents and brain damage from Alzheimer's, Parkinson's or other diseases
http://www.newswise.com/articles/2002/1/RINGS.UUT.html
University of Utah
A high-resolution color photograph
of the "living rings" may be downloaded from the university's web site
at http://www.utah.edu/unews/releases/02/jan/rings.html
Bioengineers Highlight Know-how
to Help People with Spinal Cord or Nerve Damage
As Salt Lake City prepares for the
2002 Winter Games, University of Utah bioengineers made tiny, living Olympic
Rings from nerve cells to demonstrate technology that someday might help
repair spinal cord injuries from accidents and brain damage from Alzheimer's,
Parkinson's or other diseases.
"It shows the public the biomedical
research community's level of achievement, just as the Olympic Games demonstrate
a high level of athletic accomplishment," said Patrick Tresco, an associate
professor of bioengineering and director of the university's Keck Center
for Tissue Engineering.
The "living rings" icon of five interlinked
rings measures 3.4 millimeters - about one-eighth inch long. The body of
each nerve cell - glowing as bright red dots in a fluorescence microscopic
picture of the rings - measures 20 microns, or two-fifths the width of
a human hair. Each nerve fiber or axon in the rings is one micron wide
- about one-fiftieth the width of a human hair.
The nerve cells grew on a bioengineered
scaffold made of other cells, which in turn grew on a plastic material.
The "living rings" were made in December
by graduate student Mike Manwaring, a native of Pleasant Grove, Utah, in
response to a challenge Tresco issued to his lab staff.
"The objective of our lab is to control
cell behavior on materials," Tresco said. "So I challenged the group to
create a living symbol of the Olympic Winter Games - using living nerve
cells and tissue engineering technology."
Tresco presented a photograph of
the living rings to Utah Gov. Mike Leavitt when the governor toured Tresco's
laboratory on Dec. 20 to learn about tissue engineering.
Years from now, the technology being
developed in labs such as Tresco's may be used to reconnect damaged nerves
in people with traumatic brain injury or spinal cord injury, or to help
connect transplanted nerve cells to the appropriate places in people with
brain disorders like Parkinson's or Alzheimer's diseases.
"We are at the earliest stages, but
we are tremendously hopeful there will be a convergence of biological discovery
and engineering know-how to help rebuild the human nervous system in the
future," Tresco said.
He estimated it would take at least
a decade and considerable capital investment before severed or damaged
spinal cords can be repaired or damaged nervous systems can be rewired.
There are numerous hurdles, including "our lack of knowledge of how the
nervous system is wired," he said.
"It's one thing to get nerve cells
to grow in a dish like this," Tresco said. "It is orders of magnitude more
difficult to have this occur in a damaged nervous system. For one thing,
we don't have the blueprint of how all the individual nerves are connected
at present."
Tresco said the technology eventually
might be used in several ways, including:
-- A bridge of bioengineered material
- perhaps an injectable gel or a solid bundle of biodegradable material
like that now used in surgical sutures - could be placed next to a severed
spinal cord or other damaged nerve so that new nerve fibers could grow
along the bridge and bypass the damaged area.
-- Stem cells or embryonic cells
capable of growing into nervous system tissue might be transplanted to
replace damaged nerves. Such cells might be used together with a bridge
of bioengineered material.
A major challenge is for researchers
to learn "how to get nerves to grow in specific directions," Tresco said.
The living rings were made using
materials that, in certain cases, were different than the materials that
would be used in attempting to repair nerve damage in human patients.
HOW THE LIVING RINGS WERE MADE
The first steps in making the living
rings resulted in a mold made by a photolithographic process like that
used to make circuit boards or tiny objects known as microelectromechanical
systems (MEMS).
(1) A high-quality printer was used
to make a tiny pattern or "mask" in the shape of the Olympic Rings.
(2) Photoresist, a plastic-like polymer
substance, was sprayed on a piece of brass.
(3) The mask in the shape of the
rings was put on top of the coated brass. Then the coated brass with the
mask was exposed to ultraviolet light for a few minutes. That affixed the
plastic coating to the brass, except where the mask was located, leaving
a mold in the shape of the rings.
(4) The rings-shaped mold then was
etched with acid to make it deeper.
(5) Rubbery silicone was poured over
the mold, creating a tiny set of rings.
(6) Heat-moldable clear plastic (polystyrene)
was pressed against the silicone rings under heat and pressure, creating
a new, transparent mold of the rings.
(7) A protein named fibronectin was
made to stick to the mold. Fibronectin is a protein normally found in and
around cells in various tissues in the body.
(8) Then the mold of the rings was
put in a culture dish with a liquid to promote growth. Meningeal fibroblasts
- cells that form the connective tissue surrounding the brain and spinal
cord - were added. The fibroblasts were cultured for four days with the
fibronectin-coated mold of the rings. As a result, the fibroblasts aligned
themselves so they grew within the mold, forming live scaffolding in the
shape of the Olympic Rings.
(9) Nerve cells or neurons were taken
from adult rats, specifically from the dorsal root ganglion - a set of
nerve cells that is located just outside the spinal cord and that relays
sensory information like temperature and pressure from skin and muscles
to the brain. The nerve cells were placed in the culture dish along with
the scaffolding shaped like the rings. The nerve cells were grown for 96
hours, during which they stuck to the fibroblast cells and grew new nerve
fibers along the shape of the rings.
(10) To make a photograph of the
tiny living rings, antibodies tagged with a fluorescent red dye were added
to the culture dish. The antibodies attach to proteins made by the living
nerve cells. The living rings were placed under a microscope attached to
an electronic camera. The microscope detects only the fluorescent red color.
The resulting photograph shows the living rings, with nerve cell bodies
glowing brightest red, and nerve fibers and underlying fibroblast cells
glowing with a less intense red.
Contacts:
University of Utah Public Relations
-- Patrick Tresco, associate professor
of bioengineering - work (801) 581-8873, lab (801) 585-5890, home (801)
572-4237
-- Coralie Alder, director of public
relations - work (801) 581-5180, cell (801) 556-8405
-- Lee Siegel, science news specialist,
university public relations - (801) 581-8993, cell (801) 244-5399,
© 1995-2002 Newswise
14-Jan-2002
201 S Presidents Circle, Room 308
Salt Lake City, Utah 84112-9017
(801) 581-6773 fax: 585-3350