Stem cells and tissue-specific cells can be grown in abundance from mature mammalian cells simply by blocking a certain membrane protein, according to scientists at the University of Pittsburgh School of Medicine and the National Institutes of Health (NIH). Their experiments, reported today in Scientific Reports, also show that the process doesn't require other kinds of cells or agents to artificially support cell growth and doesn't activate cancer genes.
Scientists hope that lab-grown stem cells and induced pluripotent stem (iPS) cells, which have the ability to produce specialized cells such as neurons and cardiac cells, could one day be used to treat diseases and repair damaged tissues, said co-author Jeffrey S. Isenberg, M.D., associate professor, Division of Pulmonary, Allergy and Critical Care Medicine, Pitt School of Medicine.
"Even though stem cells are able to self-renew, they are quite challenging to grow in the lab," he said. "Often you have to use feeder cells or introduce viral vectors to artificially create the conditions needed for these cells to survive and thrive."
In 2008, prior to joining Pitt, Dr. Isenberg was working in the National Cancer Institute (NCI) lab of senior author David D. Roberts, Ph.D., using agents that block a membrane protein called CD47 to explore their effects on blood vessels. He noticed that when cells from the lining of the lungs, called endothelium, had been treated with a CD47 blocker, they stayed healthy and maintained their growth and function for months.
Dr. Roberts' NIH team continued to experiment with CD47 blockade, focusing on defining the underlying molecular mechanisms that control cell growth.
They found that endothelial cells obtained from mice lacking CD47 multiplied readily and thrived in a culture dish, unlike those from control mice. Lead author Sukhbir Kaur, Ph.D., discovered that this resulted from increased expression of four genes that are regar
|Contact: Anita Srikameswaran|
University of Pittsburgh Schools of the Health Sciences