Windpipe defect repaired in womb with non-embryonic stem cells still raises ethical issues

Dianne N. Irving
Copyright October 9, 2005
Reproduced with Permission

While every new success with the use of non-human embryonic stem cells is indeed exciting and hopeful, it might not be wise to overlook the other requirements needed for truly ethical research. Special caution needs to be exercised when the subjects of such research are pre-born in utero human beings.

Why? Consider just a few issues of concern, none of which might be resolved if applying the current federal guidelines for the use of human subjects in research (OHRP federal regulations):

• (1) How reliable and accurate are the methods and techniques used to diagnose such defects, much less the ability of the technician or researcher to interpret such data? The reading of any X-rays or other similar diagnostic tools can often be erroneous (as in the numerous false diagnoses of preborn children having Downs' Syndrome, only to be discovered later as being normal).
• (2) The article is addressing therapeutic research -- not standard medical care. As research, the first levels of clinical trials (required before FDA approval as a standard medical procedure) would not be for the direct benefit of the unborn human patients used, but rather for the "advancement of science" -- for the accumulation of data on the materials and methods used. "Research" is research -- whether purely experimental or therapeutic. (See, e.g., the Declaration of Helsinki, and the Nuremberg Code).
• (3) Such therapeutic research would require a large number of trials simply for biostatistical reasons -- that is, a large number of unborn children would need to be used as research subjects in order for the data to be statistically relevant (required before publication of the studies in most journals).
• (4) Unfortunately, the issue of the use of "controls" in such research has never been ethically settled. That is, in order to obtain more "meaningful" data, the same medical research procedures would have to be performed on "healthy" normal preborn children as "controls" (for comparison purposes) to each of the preborn children used in these experiments.
• (5) Since these unborn children are not able to give ethically or legally valid informed consent themselves, such consent would necessarily have to be obtained from the parents. These days, most such "informed consent" is required only of the mother; the father is rarely involved. Will those "consenters" really be fully "informed" about all the medical/research facts involved (including the accurate biological developmental facts of their unborn children, and a thorough explanation of the various elements of the research designs and protocols), truly "free" to give such consent (without undo psychological duress and pressure, especially from researchers interested and having a stake in such research), and "consenting" for the direct benefit of their unborn children as well as for other "social" reasons?
• (6) Will women about to abort their unborn children be asked to give their "autonomous" consent to allow such research before the abortion (since their unborn children "are going to die any way, and might as well get some useful information out of them")?

Just some examples of a few other ethical issues inherently involved in such promising and exciting therapeutic research involving the use of non-human embryonic stem cells and unborn children.

http://news.bbc.co.uk/go/pr/fr/-/1/hi/health/4313226.stm

BBC News
October 8, 2005

Windpipe defect repaired in womb

Stem cells from amniotic fluid have been used to repair windpipe defects in unborn lambs while still in the womb.

A team at the Children's Hospital Boston used the cells to grow sections of cartilage tube, which were then implanted into the unborn lambs.

Details were presented at an American Academy of Pediatrics conference.

Windpipe defects in humans are rare, but life-threatening - requiring immediate surgery to cut the risk of neurological complications.

Surgeons have tried various fixes, such as grafting in pieces of the baby's rib or pelvic bone, or using synthetic substances like Teflon.

However, these have had only limited success and carry a risk of complications, such as infection or narrowing of the windpipe.

The new technique is one of several tissue-engineering approaches pioneered by the Boston team to create patches to fix birth defects - but the first to be tested on embryos.

The team chose to work on lambs as they grow quickly and are similar in size to human babies.

Collecting cells

They collected a small quantity of mesenchymal stem cells from the amniotic fluid.

These cells have the potential to develop into many different tissues, such as muscle, bone and cartilage.

The cells were cultured in the lab, "seeded" onto biodegradable tubes and exposed to growth factors to stimulate them to differentiate into cartilage tissue.

Once the grafts had matured they were used to reconstruct defective windpipes in seven foetal lambs.

Five lambs survived to term, all were able to breathe spontaneously at birth - four of them with no sign of respiratory distress.

Lead researcher Dr Dario Fauza said the windpipe is not needed before birth, so this would be an ideal time to carry out repairs.

He added: "Foetal healing is very good - it's better than adult healing."

In addition, using the body's own stem cells to grow a graft minimises the risk of rejection.

Dr Fauza has submitted an application with the US Food and Drug Authority to grow grafts from cells taken from human amniotic fluid.

Dr John Moore-Gillon, a lung specialist at Bart's hospital in London and president of the British Lung Foundation, said: "Defects in the trachea of new-born babies can be extremely difficult to deal with and may cause death or life-long disability.

"This is still very early days in the development of new treatments but we may be seeing the beginnings of a brighter future for the tiny sufferers of these terrible problems."

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