DURHAM, N.C. -- 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 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, M.D., 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. When they injected pleiotrophin into mice that had received bone marrow-suppressive radiation, they observed a 10-fold increase in bone marrow stem cells compared to untreated mice. "These results confirmed that pleiotrophin induces stem cell regeneration following injury," said Chute.
20 years from now this will seem like the dark ages of stem cell treatment. The scientists are making useful and promising advances. But the point of really fast uptake of stem cell therapies still lies some years in the future. The stem cell therapies that exist today are for fairly small fractions of the population.
I expect stem cell therapies to really take off once some exist that improve appearances. Rather than wait for illness people will go for treatment in much larger numbers when plastic surgeons can sell stem cells that make gray hair brown or black or blond again. People will also flock in to get skin stem cell therapies that turn back the clock on appearances.
Since plastic surgeons seem more inclined to try new treatments I expect any discovery of a hormone for boosting, say, hair follicle melanocyte pigment producing cells will get a very rapid roll-out. Or a hormone that boosts collagen-producing cell growth will find a market quickly.
|Share |||Randall Parker, 2010 March 21 11:46 PM Biotech Stem Cells|