Skin cells produce library of diseased stem cells
By Maggie Fox, Health and Science EditorThu Aug 7, 12:01 PM ET
U.S. stem cell experts have produced a library of the powerful cells using ordinary skin and bone marrow cells from patients, and said on Thursday they would share them freely with other researchers.
They used a new method to re-program ordinary cells so they look and act like embryonic stem cells -- the master cells of the body with the ability to produce any type of tissue or blood cell.
The new cells come from patients with 10 incurable genetic diseases and conditions, including Parkinson's, the paralyzing disease amyotrophic lateral sclerosis, or ALS, juvenile diabetes and Down's Syndrome.
Writing in the journal Cell, the team at Harvard Medical School and Children's Hospital in Boston said the point is not yet to treat anyone, but to get as many researchers as possible experimenting with these cells in lab dishes to better understand the diseases.
"This is just the first wave of diseases," said Dr. George Daley, who is also a Howard Hughes Medical Institute investigator.
The new cells are called induced pluripotent stem cells, or iPS cells, and are made using four genes that reprogram an ordinary adult cell into a primitive stage resembling the first days of a human embryo -- a method pioneered by Shinya Yamanaka of Kyoto University in Japan.
WHAT GOES WRONG
"They allow researchers ... to watch the disease progress in a dish, to watch what goes right or wrong," said Harvard's Dr. Doug Melton, who will head up the distribution of the cells. "I think we'll see in the years ahead that this opens the door to a new way of treating degenerative diseases."
Every cell in the human body contains the same genetic instructions, and in people with inherited genetic diseases, every cell carries the same mistakes, Daley and Melton said.
Stem cells -- and the new iPS cells -- will grow virtually immortal in the lab, and given the right conditions, can be made to form any desired tissue, from heart muscle to brain cells.
One day these might be used as tailor-made patches to fix diseased or damaged organs, but right now Melton said it is important to simply understand the diseases.
"We don't even know when a patient gets diabetes if each patient gets it the same way," Melton said. "There could be 50 different ways."
One thing his lab will do is try to make pancreatic beta cells -- the cells that make insulin and are destroyed in type 1 diabetes -- and study them to see what may be different among patients with the disease.
While the cells are an alternative to the more controversial embryonic stem cells, taken from a human embryo, Daley and Melton are adamant that they do not replace them.
For one thing, viruses are used to carry the transformative genes to make the iPS cells. Daley says cloning technology is still superior. "The egg does it faster and better," he said.
The federal government severely restricts embryonic stem cell research because of moral objections, but the Harvard lab works with private funding.
Melton said researchers can get batches of cells from the lab to grow on their own. Other cell types they have made to date include samples from people with Huntington's disease, a form of combined immunodeficiency commonly known as "bubble boy's disease," Lesch-Nyhan syndrome, Gaucher's disease, and two forms of muscular dystrophy.
(Reporting by Maggie Fox; editing by Julie Steenhuysen and Stacey Joyce)