Andre Penner/AP
A researcher holds a test tube filled
with stem cells.

Stem Cell Breakthrough May Eliminate Need for Embryonic Cells

March 02, 2009 12:02 PM
by findingDulcinea Staff
Scientists have discovered a safer method to create pluripotent stem cells, which could potentially eliminate the need to use embryonic cells in stem cell research.

Breakthrough Creates iPS Cells Without Using Viruses

British and Canadian researchers reveal in the March 1 issue of the journal Nature that they have discovered a process to create induced pluripotent stem (iPS) cells without using viruses. The discovery could allow iPS cells, which function similarly to embryonic cells, to be used in patients.

“It is a step toward the practical use of reprogrammed cells in medicine, perhaps even eliminating the need for human embryos as a source of stem cells,” said researcher Keisuke Kaji of the MRC Centre for Regenerative Medicine at Edinburgh University.

Embryonic cells are considered the most valuable stem cells because they are able to become any of the over 200 types of tissue in the human body. There are, however, many ethical and moral concerns over the use of embryonic cells, which require that a fertilized egg be destroyed.

Former President George W. Bush imposed strict restrictions on the use of embryonic stem cell research in 2001. President Barack Obama is likely to lift the ban and a bill calling for federal funding of the research has been introduced to the Senate.

Opponents of embryonic stem cell research argue that, with the most recent advance in the creation of iPS cells, it is no longer necessary to to use embryonic cells. “No administration that values science and medical progress over politics will want to divert funds now toward that increasingly obsolete and needlessly divisive approach,” said Richard M. Doerflinger of the U.S. Conference of Catholic Bishops.

However, scientists are cautious about the discovery, saying that the widespread use of iPS cells is still years away. “For the time being I think it rather premature to suggest that their work will completely remove the need to derive human stem cells from embryos,” said Robin Lovell-Badge, head of the MRC National Institute for Medical Research, to the BBC.

Background: Advances in the creation of iPS cells

The research builds on work by Shinya Yamanaka of Kyoto University, who in 2006 was the first to discover that mouse skin cells could be transformed into embryonic-like cells by ferrying four genes into the skin cell. In November 2007, a team led by Yamanaka and a separate team in Wisconsin each created iPS cells from human skin cells using genetically modified viruses.

Though the process was effective in creating iPS cells, it was very dangerous because the retroviruses could integrate their genes into the new cells’ DNA and cause cancer in patients. The process was improved in September 2008, when scientists created iPS cells using an adenovirus, which does not integrate its DNA into cells.

The most recent advance uses a trick called “piggyBac” to create an iPS cell without the use of any virus. “After triggering the cells to transform, the genes vanished without a trace, and with them went the risk that they could trigger cancer,” describes Bloomberg.

Reference: Stem cells explained, Nature article


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