Scientists identify stem cell growth factor
Scientists at Duke University Medical Center have identified a new
growth factor that stimulates the expansion and regeneration of
hematopoietic (blood-forming) stem cells in culture and in laboratory
animals.
The discovery, appearing Sunday in the journal Nature Medicine, may
help researchers overcome one of the most frustrating barriers to
cellular therapy. The fact that stem cells are so few in number and so
stubbornly resistant to expansion.
Researchers believe that umbilical cord blood could serve as a
universal source of stem cells for all patients who need a stem cell
transplant, but the numbers of stem cells in cord blood units are
limited, so there is a clinical need to develop a method to expand cord
blood stem cells for transplantation purposes.
“Unfortunately, there are no soluble growth factors identified to
date that have been proven to expand human stem cells for therapeutic
purposes,” said John Chute, a stem cell transplant physician and cell
biologist at Duke and senior author of the paper.
Chute, working with Heather Himburg, a post-doctoral fellow in his
laboratory, discovered that adding pleiotrophin, a naturally- occurring
growth factor, stimulated a ten-fold expansion of stem cells taken from
the bone marrow of a mouse.
They also found that pleiotrophin increased the numbers of human cord
blood stem cells in culture that were capable of engraftment in
immune-deficient mice.
Reuters |