Stem Cell - Archive

Japanese Team May Have Found The "Perfect" Stem Cell (7/07)

Since its publication in the journals Nature and Stem Cell on June 7, a report that Japanese researchers have produced embryo-like stem cells from the somatic (body) cells of mice has made headlines around the world and prompted speculation that the scientific community's brief obsession with cloning experiments for stem cell research is about to end…

[this has caused a huge shake-up in the stem cell research world, as more documentation forced acceptance in November 2007


…Shinya Yamanaka of Kyoto University…told the London Times in an interview, "Neither eggs nor embryos are necessary. I've never worked with either." Yamanaka was in Britain presenting his findings to a conference on stem cell research at the University of Manchester.
Yamanaka's experiments involved a mouse skin cell into which was introduced four proteins which "reprogram" the cell's nuclear DNA making it pluripotent – having the same qualities as a stem cell taken from a very early-stage embryo.
Stem cells are those the body produces to replace and renew tissues. As such, they are sought by researchers for medical applications in curing diseases and injuries. Adult stem cells are now commonly used in some forms of cancer treatment and have seen success in experimental treatments of Parkinson's disease and diabetes, among others.
Most researchers in stem cells agree that stem cells found in various parts of the body are, to greater or lesser degrees, limited in the different types of tissue they can produce. The pressure to obtain embryonic stem cells derives from their so-called "pluripotency," the characteristic of the mass of cells found inside the embryo in the first week of its life that make them able to form every type of tissue in the body.
If the Japanese team's claims are accurate, the discovery of a method of creating pluripotent stem cells exactly matched to the patient without killing an embryonic human being, could prove to be the "holy grail" of stem cell research, the equivalent of "transforming lead into gold". 

Dr. Yamanaka’s report riveted the attention of biologists elsewhere.

Two other teams set out to repeat and extend his findings, one led by Rudolf Jaenisch of the Whitehead Institute and the other by Kathrin Plath of the University of California, Los Angeles, and Konrad Hochedlinger of the Massachusetts General Hospital.

Dr. Yamanaka, too, set about refining his work. In the articles being published in Nature and a new journal, Cell-Stem Cell, the three teams show that injection of the four genes identified by Dr. Yamanaka can make mouse cells revert to cells that are indistinguishable from embryonic stem cells: 6 June 2007,
The attempt to create or discover embryo-like stem cells without recourse to embryos has occupied researchers for years and has been the source of a number of false alarms, most notably that of disgraced Korean doctor, Hwang Woo-suk who was found to have falsified his findings. Dr. Hwang claimed to have created cloned stem cells genetically matched to patients.
Another claim to have found this stem cell "holy grail" was that of Dr. William Hurlbut a professor at Stanford University, who, in 2004, proposed the creation of "quasi-embryos" that would yield such pluripotent cells. Hurlbut claimed in a paper that these quasi-embryos, while being created from human materials, did not qualify as "morally" human.
"Even if they're human – without that principle of life, are not moral entities," he said.
This suggestion, while it gained support among some pro-life advocates, was roundly condemned by others. Dr. Clem Persaud, a retired Professor of Microbiology and Biotechnology, called the proposal "deeply flawed." He said that the process would not create an unknown 'new entity,' but a severely disabled, cloned human being. asked Dr. John Shea, medical ethics consultant to Canada's pro-life lobby, Campaign Life Coalition, whether the Japanese research was another such false alarm.

Shea was circumspect but hopeful saying that the paper appears to present a legitimate breakthrough that may lead to an ethical solution to the embryo and cloning debate. From his reading of the report, Shea said it appears the Japanese team has produced pluripotent embryo-like stem cells similar to blastomeres, those cells found in the earliest stages of embryonic life, but have not created embryos.
He cautioned, however, "The trouble with a blastomere, if that is what they've got, is that it can form a twin, becoming an embryo itself through the well known process of regulation."

The conditions under which such cells could be used ethically, he said, would have to be very strictly controlled.
Canadian Biotechnology Expert Denounces the Creation of 'Quasi-Embryos' as "Morally Repugnant"
[20July07, Manchester, Hilary White,]