Researchers at U.K.-based Kingston University have discovered in the umbilical cord blood of infants primitive stem cells that are similar to those from human embryos and that can develop into any tissue in the body. The newly discovered human cells, called "cord-blood-derived embryonic-like stem cells" or CBEs, are more versatile than adult stem cells that are found in bone marrow and that can mend damaged tissue.
Separating adult from CBE stem cells, the scientists can extract as many as 10,000 primitive cells from the umbilical cord blood. The scientists then use a micro-bioreactor to generate millions more, according to Dr. Colin McGuckin, director of the Stem Cell Therapy group at Kingston University.
So far, the scientists have successfully formed liver tissue from the cells, and they're now working to replicate pancreatic and nerve tissue.
"We're merging the two technologies: our stem cells with bioreactor engineering technology," said McGuckin. "We're helping to keep cells in a small, neat environment that helps them to replicate."
McGuckin's research was published in NewScientist this week.
Taken together, the discovery could offer an alternative to controversial embryonic stem cell research, which has touched off an ethical and political debate in the United States. Stem cell research uses cells from human fetuses that are later destroyed--a process that has drawn the ire of pro-life advocates and caused President George W. Bush to cut federal funding for the research in the United States. Umbilical cord blood can likely be multiplied without the same ethical dilemmas.
Synthecon, a NASA spin-off company based in Houston, originally developed the microgravity technology 10 years ago for use aboard the International Space Station to test plant and cancer cells. The bioreactor is a cell-culture system designed to create a microgravity environment that allows cells to reproduce.
The reactor keeps the cells in the constant process of free floating, McGuckin said, to allow them to reproduce much the way they would in the womb. When an embryo attaches to the wall of the mother's womb, it is held three-dimensionally without lying flat, he said. Similarly, the cells couldn't multiply as fast in a two-dimensional environment of a petri dish.
Synthecon has designed tiny bioreactors for stem cell work. McGuckin said that he and his team use bioreactors up to 40 millimeters long that sit in the palm of the hand.
The team hopes eventually to use one unit of cord blood to replicate tissue for one patient. The bioreactors can increase the stem cell count 168-fold, McGuckin said.