TORONTO, Sept. 5 /CNW/ - Researchers at The Hospital for Sick Children
(SickKids) and the University of British Columbia (UBC) have used skin-derived
stem cells to repair spinal cord injuries in rats. This research was made
possible with the support of a $1.5-million NeuroScience Canada Brain Repair
Program(TM) team grant that enabled scientists from across Canada to work
together and fast track their research. This research is reported in the
September 5, 2007 issue of the Journal of Neuroscience.
Skin-derived precursors (SKPs) are self-renewing stem cells that reside
within the dermis of both rodents and humans and share characteristics with
embryonic neural crest stem cells, which are responsible for the generation of
the nervous system. The most important characteristic being their ability to
turn into neural crest derived cell types like peripheral neurons.
"We previously discovered that SKPs can efficiently generate a type of
glial cell, called Schwann cells that have been shown to provide a good growth
environment for injured central nervous system axons," said Dr. Freda Miller,
the study's principal investigator, a senior scientist in Developmental
Biology in the SickKids Research Institute, a professor of Molecular and
Medical Genetics, and Physiology at the University of Toronto, Howard Hughes
Medical Institute International Research Scholar and Canada Research Chair in
Developmental Neurobiology. "These types of axons normally do not regenerate."
The mammalian spinal cord does not recover well following injury. This is
due to secondary damage to the spinal cord and surrounding tissue, and loss of
a conductive insulation on axons called myelin, as well as the failure of
axons to overcome myelin-associated inhibiting molecules.
Studies have shown that Schwann cells help promote axonal regeneration
and that transplantation of these cells facilitates the remyelination of the
injured spinal cord. However, Schwann cells cannot be harvested without
invasive surgical biopsies and there are substantial difficulties with
purifying the cells once they have been extracted.
"Knowing that harvesting Schwann cells from nerves is invasive and
difficult, we wanted to test whether SKPs could be used to repair the injured
rat spinal cord," said Dr. Wolfram Tetzlaff, professor at the University of
British Columbia, associate director of ICORD (International Collaboration on
Repair Discoveries) and Edie Ehlers Chair in Spinal Cord Injury Research. "To
do this the Miller lab isolated and expanded genetically-tagged SKPs,
differentiated them into Schwann cells and we transplanted them directly into
the injured rat spinal cord."
Analysis after 12 weeks following transplantation revealed that the
SKP-derived Schwann cells survived well within the injured spinal cord,
reduced the size of the contusion cavity, myelinated endogenous host axons,
and recruited endogenous Schwann cells into the injured cord.
These results indicate that transplantation of SKP-Schwann cells
represent a viable alternative strategy for repairing the injured spinal cord.
Cells to repair a spinal cord injury could be taken from the injured
individual's own skin potentially bypassing issues of transplanted cell
rejection during the healing process.
"This is an important discovery for the millions of Canadians who suffer
from spinal cord injuries and the millions more with other central nervous
system disorders," said Inez Jabalpurwala, President of NeuroScience Canada.
"The work of Dr. Miller and her team could soon treat, and one day cure,
patients with spinal cord injuries, and allow them to be active again in our
society. Spinal cord injuries cost the Canadian economy billions of dollars,
including healthcare costs and lost productivity," added Ms. Jabalpurwala.
Other key researchers on this paper were Jeff Biernaskie from SickKids
and Joeseph Sparling from the University of British Columbia.
Other funders of this research through salary support were the Canada
Research Chair program, Canadian Institutes of Health Research, Howard Hughes
Medical Institute, Michael Smith Foundation of Health Research, Parkinsons
Society of Canada, The Rick Hansen Foundation and SickKids Foundation.
NeuroScience Canada (which represents the functional integration of the
NeuroScience Canada Partnership and NeuroScience Canada Foundation) is a
national, non-profit organization that develops and supports collaborative,
multidisciplinary, multi-institutional research across the neurosciences. By
partnering with the public, private and voluntary sectors, NeuroScience Canada
connects the knowledge and resources available in this area to accelerate
neuroscience research and funding, and maximize the output of Canada's
world-class scientists and researchers. In 2006, NeuroScience Canada received
The Conference Board of Canada/Spencer Stuart National Awards in Governance
award for the non-profit sector.
The mission of NeuroScience Canada's Brain Repair Program is to
fast-track neuroscience research in order to develop treatments and therapies
more quickly. Through the Brain Repair Program, NeuroScience Canada and its
donors and partners are investing $8 million to support five research teams
conducting breakthrough work in the area of brain repair.
UBC is one of the world's great public universities. Newsweek magazine
ranked UBC 27th in 2006; UBC was ranked 38th in the Times Higher Education
Supplement in 2005; and for the past four years UBC has been among the top
40 institutes in the world as ranked by the Shanghai Jiao Tong University. UBC
ranks in the top 10 of North American universities in creation of spin-off
companies, has particular strengths in biotechnology, and its research
generates more U.S. Patent applications than any other Canadian institution.
The Hospital for Sick Children (SickKids), affiliated with the University
of Toronto, is Canada's most research-intensive hospital and the largest
centre dedicated to improving children's health in the country. As innovators
in child health, SickKids improves the health of children by integrating care,
research and teaching. Our mission is to provide the best in complex and
specialized care by creating scientific and clinical advancements, sharing our
knowledge and expertise and championing the development of an accessible,
comprehensive and sustainable child health system. For more information,
please visit www.sickkids.ca. SickKids is committed to healthier children for
a better world.
For further information:
For further information: Lisa Lipkin, Public Affairs, The Hospital for
Sick Children, (416) 813-6380, email@example.com; Hilary Thomson, Public
Affairs, University of British Columbia, (604) 822-2644,
firstname.lastname@example.org; Dominique Godbout, NeuroScience Canada, (514) 989-2989,