MEDICAL SCIENCE: by Babette FrancisNews Weekly
New developments in stem-cell science
, April 14, 2007
Why are scientists so intent on cloning humans, when medical miracles are being achieved every day with non-embryonic stem-cells, asks Babette Francis.Recently, a Melbourne television news program reported a man had damaged vision in one eye substantially cured by the transfer of a single stem-cell from his other eye. The man said how much his life had improved after the procedure.
The report reminded me of the proverb, "There are none so blind as those who will not see".
Why are scientists intent on cloning, when daily miracles are being achieved with non-embryonic stem cells? Is it to satisfy their egos and establish the principle that no restrictions whatsoever may be placed on scientific research?
Cloning legislation in Victoria is a confidence trick on taxpayers. Though there have been no restrictions on embryo experimentation in countries such as Singapore and the United Kingdom, embryonic stem-cells (ESCs) have produced no medical cures but only heaps of tumours in animals.Fraud
Cloning has yet to be achieved with human cells. What has
been "achieved" is the fraud perpetrated by South Korea's Dr Hwang Woo-Suk.
What ESC scientists are after is taxpayers' money, because they are unable to attract much private investment. The "market" knows the truth.
Adult stem-cells (ASCs), which include stem cells from cord blood and placentas, treat more than 70 diseases and are involved in 1,300 clinical trials. Scientists keep discovering that ASCs produce a wide variety of mature cells. The most promising development was reported in the January issue of Nature Biotechnology.
Anthony Atala, director of the Institute for Regenerative Medicine at Wake Forest University, reported that stem cells in the amniotic fluid that fills the sac surrounding the foetus may be just as versatile as embryonic stem-cells. Moreover, amniotic stem-cells possess all the advantages that have made adult stem-cells such a success.
This has caused considerable consternation among embryonic stem-cell researchers because they haven't yet had a single successful clinical trial to boast about!
A claimed advantage for ESCs was that most ASCs cannot be multiplied outside the body for long, while ESCs may replicate in the lab indefinitely. But Atala's amniotic stem-cells grow as fast outside the body as ESCs, and to date he has succeeded in growing the same cell line for two years, with no indication of slowing.
That leaves ESCs with only one "potential" advantage - they can be "differentiated" into all three "germ layers", or subtypes of cell, i.e., they should be able to be made into all of the 220 types of cells in humans.
ASCs were believed to be only capable of differentiation to a limited number of mature cells, depending on the type of ASC with which you started, e.g., a marrow cell could become any type of marrow or blood cell, but it couldn't become a muscle cell. That would be a different germ layer.
However, experiments around the world have shown that ASCs from one germ layer can be converted into those of another in a human, such as those that turn marrow cells into heart muscle and blood vessels in humans.
Amniotic stem-cells may be the most easily differentiated of all - as well as among the easiest to extract in large amounts. They are recovered during amniocentesis and can be obtained at births when amniotic membranes break.
The media have downplayed the Atala findings. The New York Times
genetics reporter, Nicholas Wade, said of Atala's paper, "It reports finding 'multipotent' stem cells in amniotic fluid. Multipotent means they can't do as much as ESCs which are 'pluripotent'."
Wade is wrong. Atala told PBS's Online NewsHour
: "We have been able to drive the cell to all three germ layers, which means all three classes of tissues available in the body, from which all cells come." The online abstract of the Atala paper indicated the same.
ESC researchers claim the new amniotic cells mean the distinction between ESCs and ASCs is "artificial". This is untrue. Extracting ESCs kills the human embryo, while adult and amniotic stem-cells can be obtained without killing the donor.
Besides causing tumours, ESCs require permanent and powerful immunosuppressive drugs because the body rejects the cells as foreign. They are also difficult to differentiate into the needed type of mature cells.
By contrast, non-embryonic stem-cells do not become cancerous, are far less likely to cause rejection and have the amazing ability to form the right type of mature cell upon being injected into a body that needs that type of cell.
It is these biological differences that have held back ESC research, not lack of funds or mean-minded right-to-life activists. Another fraud of which ESC researchers are guilty is claiming an embryo is not human life until it is implanted in a womb.
There is no justification for wasting one more cent on embryo-killing research. Our money should be spent on adult and other tissue stem-cells (amniotic, placental and umbilical) which are actually producing results, and on other areas of health concern such as heart disease, strokes, cancer - and waiting lists in hospitals.- Babette Francis, B.Sc. (Hons), is national co-ordinator of Endeavour Forum Inc.