Shinya Yamanaka, a stem cell researcher at the Gladstone Institutes, which is affiliated with the University of California, San Francisco, has won this year’s Nobel Prize in Physiology or Medicine jointly with English researcher John B. Gurdon.
Yamanaka, who is also an investigator at Kyoto University, in Japan, and a professor of anatomy at UCSF, won the prize for developing a technology to create stem cells that can become any type of cell in the body. His method creates cells that are like embryonic stem cells, without using human embryos.
These so-called induced pluripotent stem cells, or IPS cells, could one day lead to cures for a wide range of diseases, from Parkinson’s to heart disease. And they bypass the ethical issues surrounding the use of human embryos for research.
IPS cells are like embryonic stem cells in that they can be coaxed into becoming any type of cell in the body. But unlike embryonic stem cells, which are created from human embryos, IPS cells are developed by introducing a few genes into common adult cells like skin cells.
“We knew that embryonic stem cells and skin cells, although they are very different, have the same blueprint, which consists of approximately 30,000 genes,” Yamanaka told KQED News during an interview at the Gladstone Institutes in San Francisco in 2010. His method consisted in getting the skin cells to “read” the genes that give embryonic stem cells their qualities.
In announcing the award today in Stockholm, Sweden, the Nobel Committee for Physiology or Medicine said that "These groundbreaking discoveries have completely changed our view of the development and cellular specialization. We now understand that the mature cell does not have to be confined forever to its specialized state."
Yamanaka won the award jointly with John B. Gurdon, from the University of Cambridge and the Gurdon Institute, in Cambridge, England. The Nobel Committee recognized Gurdon for his pioneering work in animal cloning. In 1962, Gurdon discovered that "the specialization of cells into different tissues is reversible," said the Committee.
Yamanaka, who was an orthopedic surgeon before becoming a research scientist, became interested in stem cells as a way to potentially help patients suffering from spinal cord injuries, for which there are no treatments today. He decided to look for an alternative to embryonic stem cells in response to the controversy around the use of embryos for research.
“What I’m hoping is that by using IPS cells, which are free from ethical issues, we can speed everything up,” he said.
Though funding is available in California for researchers using embryonic stem cells, federal funds have been subject to the political pendulum. President George W. Bush restricted funding in 2001. On his first day in office in 2009, President Obama overturned Bush’s decision and made federal funding available for the research.
In 2006, Yamanaka was able to create IPS cells from mice adult cells. His big breakthrough came in 2007, when he created the embryonic-like cells from human skin cells. He then took these IPS cells, and using their ability to become any cell in the body, coaxed them into becoming heart cells. Proof of his success arrived in the form of an email from a researcher at his lab in Kyoto.
“I was in San Francisco. He sent me a video showing beating heart cells,” Yamanaka said. “But those heart cells were not from a heart. They were actually from skin.”
Treatments based on IPS cells would be based on their ability to become stem cells that could regenerate damaged cells in different organs. Yamanaka said that stem cell transplants on animals with spinal injuries have shown promising results in his lab. Clinical trials could be five years away, he said. He is also using IPS cells to test drugs against Lou Gehrig’s disease.
In addition to bypassing the ethical issues, IPS cells have another advantage over embryonic stem cells. Because they’re created from patients’ own cells, they would be less likely to be rejected by their bodies.
Since Yamanaka’s breakthrough, scientists have taken his cellular reprogramming techniques one step further and are now able to transform one type of adult cell directly into another, bypassing the stem cell stage altogether. Deepak Srivastava and his team at the Gladstone Institute of Cardiovascular Disease have created beating heart muscle cells in mice from another type of heart cell that normally becomes scar tissue after a heart attack.
Yamanaka is only the second Japanese scientist to win the Nobel Prize in medicine. In 1987, Susumo Tonegawa, from the Massachusetts Institute of Technology, received the award. Yamanaka said he plans to use his award money to fund young researchers.
Yamanaka, 50, spends a few days each month in San Francisco working at the Gladstone Institutes, where he began his research career in 1993 as a postdoctoral fellow.
He lives in Osaka with his wife, a dermatologist, and two daughters, aged 22 and 20, both of whom are in medical school.
“I’m the least busy person in my house,” he joked.
Stem cell researcher Shinya Yamanaka talks about how he created embryonic-like stem cells from skin cells; when treatments might be available, and why researchers still need to study embryonic stem cells.
QUEST's story explaining what stem cells are and how researchers hope to use them to develop treatments for heart disease.