Embryonic stem cell therapy 'best route'

By Professor Harry Moore, Centre for Stem Cell Biology, University of Sheffield

BBC News (bbc.co.uk) – December 15, 2004

ALTERNATIVE VIEW BELOW IN RED

TEXT ON UMBILICAL CORD BLOOD BELOW IN GOLD

Medical progress, by its nature, is never straightforward.

With any new treatment there are always risks and potential side effects.

But I believe the potential that stem cells offer to revolutionise the treatment of several degenerative diseases, as well as spinal cord injury, definitely merits research.

The legislation in place in the UK for embryo research since 1990, and revised in 2001, is perhaps the most advanced in the world and strictly governs what studies can be undertaken.

This is welcomed by the vast majority of doctors and scientists in the field and protects both patients and researchers.

Of course the maverick scientist will always exist (and needs to be safeguarded against).

And stem cells are not the panacea for every disease (as might be thought from all the media hype).

But, given the progress made in the last few years, some stem cell therapies may well be readily available within 10 to 15 years.

The challenge is to develop effective and safe cell therapies - which will take time, money and perseverance.

Promise

Embryonic stem cells in the laboratory retain the ability to form specific cell types such as insulin-secreting cells, nerves and heart cells.

If transplanted, these cells might halt and even cure patients of diseases such as Type 1 diabetes, Parkinson's disease or heart failure.

Transplantation studies into animals with these cells have shown much promise.

This research represents an important change in our thinking on how, in the future, we might treat these debilitating illnesses where patients require long-term care, and drugs cannot cure the condition.

Presently, a major stumbling block for cell transplantation is the lack of suitable tissue for donation.

For instance, trials to treat diabetes with pancreatic cells (which regulate blood glucose by secreting insulin) from dead donors have shown good success.

This transplantation therapy controls diabetes much better than insulin injections alone, giving patients the prospects of a much better quality of life.

But often cells from two or three donors are required to treat one patient.

This is not only very impractical but there are potential long-term risks of transmission of other blood-borne diseases to the patient.

Because embryonic stem cells proliferate indefinitely they represent an inexhaustible supply of cells, which can be cultured in quarantine conditions, free from the risk of other infectious agents.

Greatest potential

A question often asked is: why use human embryos and embryonic stem cells - would it not be more ethical to use adult stem cells from bone marrow, babies' cord blood or other tissues?

In fact adult stem cells are used to treat certain conditions.

But I, and many other scientists, believe that only embryonic stem cells have the true capacity to develop into all the different cell types of the body and therefore represent the greatest potential for future cell therapies.

Embryos are donated by couples undergoing IVF treatment after independent counselling, are surplus to their clinical need and would often otherwise be destroyed.

These donors have confidence in the regulatory framework and inspections of the HFEA and are motivated into giving embryos with the hope research will lead eventually to clinical applications.

Nevertheless, the potential of other stem cells should, and is, being explored.

Recent experiments suggest that adult stem cells may have some capacity to change into other cells for therapy.

In time, we may be able to reprogramme many cells to other functions in the body in which case early embryos and embryonic stem cells may not be necessary.

Embryonic stem cell therapy 'morally unacceptable'

By Josephine Quintavalle, Founder, Comment on Reproductive Ethics (CORE)

BBC News (bbc.co.uk) – December 15, 2004

An estimated 56 diseases have been treated with the use of adult, human stem cells.

But there are no recorded cases of treatment using stem cells derived from a human embryo.

Worldwide a huge debate rages about the ethics of stem cell research.

One side argues that no moral boundaries should be in place in this field beyond basic issues of safety.

Others, including Comment on Reproductive Ethics (CORE), insist that science must always function within an ethical framework, even if this may lead to prohibitions.

This is not a war of absolutes, however. Both sides are in favour of stem cell therapy.

The debate centres not around stem cells themselves, but about their provenance.

Where stem cells are harvested from the embryo and foetus - as opposed to the umbilical cord blood or placenta of the newborn, or the adult - existing life has to be sacrificed.

This is a trade-off which CORE simply cannot accept.

We believe we have a duty to protect human subjects from abuse, and this duty must inform all medical ethics.

Regardless of potential benefit, we must reject outright any research which results in the deliberate destruction of human life.

Alternatives

A blind woman's sight was restored this October, in the US, using stem cells. These particular cells had come not from an embryo (up to eight weeks old) but from aborted foetal tissues.

We believe that such cures should never depend on the killing of an unborn child.

Indeed, some patients have had their sight restored through corneal transplants created from their own, adult, stem cells.

This is the kind of stem cell therapy we welcome wholeheartedly and which makes up the 56 types of treatment highlighted in the opening paragraph.

It is "no" to embryo and foetal stem cells, but a huge vote of confidence in cord blood, placental and adult stem cells.

Some scientists are prepared to accord the embryo and foetus some special status and would be happier to explore ethical alternatives if these were indeed available.

But others support their destruction regardless of the alternatives.

Ill informed

It is, therefore, important to be scrupulously objective when weighing up the relevant scientific evidence.

There is far too much inaccurate or inadequate information in circulation, particularly in relationship to the potential of embryonic stem cells.

One rarely hears of the dangers associated with this kind of cell: how they can run out of control, become unstoppable and form tumours.

It is sometimes claimed that the embryos used in this research will be simply "discards" from assisted fertility treatments.

In fact, "quality" human embryos will sometimes be created deliberately for this research.

Moreover, in order to avoid problems of tissue rejection in the sick patient, some embryos will be cloned - something that many people object to very strongly.

With the therapeutic reality of adult stem cells increasing by the week, it is very difficult to justify the unfettered enthusiasm for embryo research which dominates UK science.

Even if embryonic and foetal stem cells were to prove safe and effective in forthcoming decades, the fact remains that they can only be harvested at the cost of destroying early human life.