STOCKHOLM – Shinya Yamanaka’s selection for the Nobel Prize in physiology or medicine, just six years after developing artificially derived multipurpose stem cells, has boosted hopes the technology will lead to cures for many diseases.
But the rapid pace of research into induced pluripotent stem cells, or iPS cells, by scientists around the world has also brought about a host of new concerns, ranging from ethical issues to prohibitive treatment costs.
In the traditional lecture by new Nobel medical laureates given at the Karolinska Institute in Stockholm, Yamanaka on Friday recalled setting a long-term goal for his laboratory in December 1999 when he became principal researcher at Nara Institute of Science and Technology.
Yamanaka said he wanted to “make ES-like stem cells, not from embryos, but from somatic cells from patients’ own cells,” referring to embryonic stem cells produced from fertilized eggs. “By doing this, we should be able to overcome the moral, ethical hurdle of human ES cells.”
At the time, embryonic stem cells were considered a trump card in regenerative medicine, but the concept faced ethical questions raised by the administration of U.S. President George W. Bush as well as by the Roman Catholic Church, as such cells were derived by destroying fertilized eggs, the germinating seeds of life.
Yamanaka’s breakthrough in 2006 regarding iPS cell production through somatic cells, such as skin cells, was considered epoch-making as it offered an alternative to destroying human embryos. But Yamanaka now says he “was wrong” to have assumed that the technology had cleared ethical hurdles.
On Oct. 5, three days before the Nobel prize was announced, a team led by Kyoto University professor Michinori Saito said it had succeeded in creating mice ova from iPS cells. Because the team has also succeeded in producing sperm using mice iPS cells, it has shown at least in theory that new life can be artificially created through the fertilization of the two.
Guidelines from the education and science ministry forbid fertilization of eggs and sperm derived from iPS cells. Experts say issues could arise in the future over whether to allow such technology to be used at all or to make it available, for example to gay couples wanting to have children.
“This field of research can see tremendous progress through the work of a single team,” Yamanaka said. “Unless the whole of society prepares itself for ethical debate, scientific technology will end up outpacing it.”
Another issue will be establishing priorities on how to explore treatment options for different diseases. For example, should a study into common diseases that affect a large number of people come first over studies on rare, life-threatening illnesses, or vice versa?
“There will be problems over the allocation of research funding,” said Satoshi Kodama, an associate professor of ethics at Kyoto University.
In the so-called iPS stock for keeping a reserve of iPS cells for treatment and research, issues may arise over explaining to and obtaining consent from donors considering providing cells to the bank.
As the research makes rapid progress and unforeseen results unfold from it, there may be a problem with the conventional way of obtaining donor consent. Questions could arise over whether a donor should be allowed to retract a contribution.
In addition, when the use of iPS technology becomes a reality in regenerative medicine, the cost may be “a major factor” for patients, said Takeo Asano, an official in the Cabinet Office section on innovations in health care services.
Treatment in which iPS cells are produced from patients’ own cells before they are grown into desired cells for transplant, a process taking several months, would cost millions of yen per person at the clinical research stage. It is unknown how much such treatment would cost when made available for the general public.
It may turn out to be too costly for public health insurance, and those in need could be forced to explore options in private-sector insurance products.
During the 1970s, when concerns over genetic modification using new biotechnology techniques became widespread, scientists voluntarily gathered in the United States to discuss the technology’s implications for society.
“In the area of stem cell research, we should also hold a meeting among parties, including patients’ groups and interested members of the public, to make ethics-related recommendations from Japan,” Kodama said.