Research is step toward transforming cells

WASHINGTON – Scientists have transformed one type of fully developed adult cell directly into another inside a living animal, a startling advance that could lead to cures for a plethora of illnesses and sidestep the political and ethical quagmires that have plagued embryonic stem cell research.

Through a series of painstaking experiments involving mice, the Harvard biologists pinpointed three crucial molecular switches that, when flipped, completely convert a common cell in the pancreas into the more precious insulin-producing ones that diabetics need to survive.

The feat, published online Wednesday by the journal Nature, raises the tantalizing prospect that patients suffering from not only diabetes but also heart disease, strokes and many other ailments could eventually have some of their cells reprogrammed to cure their afflictions without the need for drugs, transplants or other therapies.

“It’s kind of an extreme makeover of a cell,” said Douglas Melton, co-director of the Harvard Stem Cell Institute, who led the research. “The goal is to create cells that are missing or defective in people. It’s very exciting.”

The findings left other researchers in a field that has become accustomed to rapid advances reaching for new superlatives to describe the potential implications.

“I’m stunned,” said Robert Lanza, chief scientific officer of Advanced Cell Technology in Worcester, Mass., a developer of stem cell therapies. “It introduces a whole new paradigm for treating disease.”

“I think it’s hugely significant,” said George Daley, a stem cell researcher at Children’s Hospital in Boston. “This is a very spectacular first.”

Even the harshest critics of embryonic stem cell research hailed the accomplishment as a major, welcome development.

“I see no moral problem in this basic technique,” said Richard Doerflinger of the U.S. Conference of Catholic Bishops, a leading opponent of embryonic stem cell research because it involves destroying human embryos. “This is a win-win situation for medicine and ethics.”

Melton and other researchers cautioned that many years of research lay ahead to prove whether the development would translate into cures.

“It’s an important proof of concept,” said Lawrence Goldstein, a stem cell researcher at the University of California, San Diego. “But these things always look easier on the blackboard than when you have do them in actual patients.”

Although the experiment involved mice, Melton and other researchers were optimistic the approach would work in people.

“You never know for sure – mice aren’t humans,” Daley said. “But the biology of pancreatic development is very closely related in mice and humans.”

Melton has already started experimenting with human cells in the laboratory and hopes to start planning the first studies involving people with diabetes within a year.

“I would say within five years we could be ready to start human trials,” Melton said.

Other scientists have already started trying the approach on other cells, including those that could be used to treat spinal cord injuries and neurogenerative disorders such as Lou Gehrig’s disease.

“The idea to be able to reprogram one adult neuron type into another for repair in the nervous system is very exciting,” said Paola Arlotta, who is working in the Center for Regenerative Medicine at the Massachusetts General Hospital-Harvard Medical School, in Boston.