In the end, there may be no need to kill human embryos for getting stem cells, as two teams have achieved embryonic stem cells from human skin cells. The newly induced pluripotent cells could turn into various cell types of the human organism.
"The advantage of using [such] reprogrammed skin cells is that any cells developed for therapeutic purposes can be customized to the patient. They are probably more clinically relevant than embryonic stem cells," said lead author James Thompson, a biologist at the University of Wisconsin, Madison.
Replacement tissues and organs obtained from stem cells won't face rejection coming from the immune system, but harvesting them by killing a human embryo has triggered controversy and restricted public funding in US and not only.
First-induced pluripotent cells were obtained by a team at Kyoto University in Japan, which inserted genes into cells from the mice tails.
In the journal Science, Thompson's team describes how induced pluripotent cells were generated by inserting with the help of transporting viruses 4 genes (OCT4, SOX2, NANOG, and LIN28) into skin cells. The second research, published in the journal Cell by the Kyoto researchers, obtained induced pluripotent cells from human skin and connective tissues, using a slightly different combination of genes. The success rate of the Japanese team was of one reprogrammed cell out of every 5,000, while that of the American team was one for every 10,000.
"We should now be able to generate patient- and disease-specific [induced pluripotent stem] cells and then make various cells, such as cardiac cells, liver cells, and neural cells," said lead researcher Shinya Yamanaka of Kyoto University.
"In addition to alleviating concerns over embryonic stem cells, the new techniques may reduce the need to carry out somatic cell nuclear transfer, a controversial technique that uses harvested eggs to clone cells. If it turns out to be a good alternative, obtaining donated human oocytes [eggs] may be less important for research progress," said Sidney Golub, chair of the Human Stem Cell Research Oversight Committee at the University of California, Irvine.
Thus, cloning will no longer be required for obtaining human stem cells.
"It is not clear if this work would be eligible for federal funding under the restrictions put in place by President Bush in 2001, as the genes that were transferred were obtained from embryonic stem cells," said Golub.
Researchers warn that the pluripotent cells are not real stem cells and nobody knows their real limitations and the dangerous side would be considering embryonic stem cell research no longer a necessity.
|
No user comments yet.
Be the first to express your opinion using the form below!
