ESCs – again a redundant dud

Look at this pitifully muddled headline from the US News & World Report earlier this month:

Embryonic Stem Cells—and Other Stem Cells—Promise to Advance Treatments

Adult stem cells may reach patients first, and induced pluripotent stem cells have greatest potential

Do you spot the incoherence? That media tart, the embryonic stem cell, gets star billing in the main headline – but in the subheading and in the substance of the article, is shown (again) to be redundant.

How long will it be before there is some straight talk by scientists and journalists?

Yes indeed, adult stem cells 'may' reach patients first (correction: 'have reached' thousands of patients already, including over 2000 patients with heart disease alone) because only ASCs can be used in humans safely (i.e. they don't form tumours and don't require immune suppressive drugs). And yes indeed, iPS cells 'have greatest potential' (since in every possible measure of potential, iPS match or exceed the usefulness of ESC – again, because they are simpler to make, ethically innocent, and exactly match the patient to be studied).

Why then keep the artificial life-support on ESCs in every headline, every article ('ESCs are still the gold-standard' and other nonsense) when iPS has left it for dead? Just look at the clear statement of the superiority of iPS in this article:

"And because the (embryonic) cells are biologically foreign—like a transplanted organ—recipients will need to take powerful immunity-suppressing drugs, which have a host of side effects, to prevent rejection. It's that latter problem that makes scientists particularly excited about iPS cells, which would have the clinical potential of embryonic cells but can be created from a patient's own cells. Reprogramming an adult cell into an embryo-like, more malleable state sidesteps the issue of immune rejection, not to mention the moral debate."

And because both of these pluripotent cells naturally cause tumours, they are both inferior to ASCs for actual trials in human patients.

Ill-informed ESC puffing remains a trial of human patience, nothing more.

iPS repairs heart damage in mice

Even the opening paragraph of this paper from the Mayo Clinic is pure music...

"R egenerative medicine offers the potential of curative therapy to repair damaged tissues.
Pluripotent stemcells derived from the inner cell mass of early-stage embryos have provided a prototype for multilineage repair. Ethical considerations along with practical limitations, however, have precluded adoption of embryonic stem cell platforms, driving advances in nuclear reprogramming to establish viable alternatives.
In this regard, induced pluripotent stem cell (iPS) technology provides an emerging innovation that promises the unlimited potential of embryonic stem cells while circumventing the need for embryonic sources".

A very cute bit of research - although I always seem to be a party-pooper, reminding excited people that while iPS is useful for genetic research and drug testing, it is no more feasible for direct implantation into humans than are ESC, as both are pluripotent and therefore tumorigenic; only the lowly ASC can be safely used (and has been used now in over 2,000 humans with heart disease... eg at John Hunter in Newcastle, Victor Chang in Sydney...never mind little white mice).

Always, however, the point is this: that if ESCs are useful for anything at all, iPS have the identical, exact same usefulness - and more, because iPS is a genetic match to the patient, while ESC is not.

But readers of this Blog understand that...

Here is the Reuters report on the paper:

Embryonic-like cells repair damaged mouse hearts Mon Jul 20, 2009

CHICAGO (Reuters) - Ordinary cells reprogrammed to act like embryonic stem cells can help repair damaged heart tissue in mice, researchers reported on Monday in a study that shows a potential practical use for the experimental cells.

When injected into mice whose hearts had been damaged by a heart attack, the new cells helped improve both the structure and function of the heart. Eventually the hope would be to patch up seriously ill heart patients using their own cells.

"It was obvious to the observer which animals had been treated and which ones hadn't," said Dr Timothy Nelson of the Mayo Clinic in Rochester, Minnesota, whose study appears in the journal Circulation.

The team used a promising new type of embryonic-like stem cell called an induced pluripotent stem cell, or iPS cell, made from ordinary cells. Many teams are using this new technology to look for ways to repair the body, a fast-growing field of research known as regenerative medicine.

Like embryonic stem cells, induced pluripotent stem cells have the ability to form any kind of cell in the body. Because they come from adult tissue, their use is less controversial than embryonic stem cells, which come from days-old embryos.

etc etc… Read the full report at http://www.reuters.com/article/scienceNews/idUSTRE56J51M20090720

Industry loves it: iPS from a simple blood sample

Look at this new bit of good news where James Thomson’s company makes iPS from human blood – so any old blood sample can now become that ‘liquid gold’ that the cloning fantasists once claimed was to be found on their dig alone. Look at this summary comment about these iPS cells being just exactly the same as ESC, thank you vey much…

“Analysis revealed that the iPS cells are functionally identical to embryonic stem cells and iPS cells generated from other human tissue sources, that they carry the same genetic background as the source blood sample, and that they have the pluripotent ability to differentiate into any cell type.”

Cloning embryos has never achieved even a single patient-specific pluripotent stem cell, while iPS is achieving that goal with embarrassing ease.

What justification is left, then, for even attempting to clone human embryos – when the longed-for genetically-matched stem cells can be obtained so simply and ethically?

iPS is meeting all the goals of science and industry:

"Industry's challenge was to reliably create iPS cells from a commonly available and easily accessible tissue source and we focused on stored human peripheral blood samples," said Chris Kendrick-Parker, chief commercial officer of CDI. "Generating pluripotent stem cells from small volumes of blood, either freshly collected from a patient or accessed from blood storage repositories, provides a convenient source for generating patient-specific stem cells that are valuable research tools and may one day be used as a cellular therapy to treat disease."

Have no doubt: industry is going to drive the ethical alternative of iPS because it is a winner. SCNT cloning is a failed fantasy, a diseased fruit blighting the vine of stem cell science.

Media Release: ‘Sperm from Embryonic Stem Cells’ – a wanton abuse of embryos

FOR IMMEDIATE RELEASE –

 

"The abuse of embryonic humans reached a sinister new low today with the announcement that scientists in Newcastle, UK, have derived functional sperm from embryonic stem cells" said Dr David van Gend, national director of Australians for Ethical Stem Cell Research.

 

"This is an abuse both because of its implications – namely, that scientists can now exploit a dead embryo as a source of sperm – but also because it was entirely unnecessary to use embryos as the source of stem cells. That was an ethically wanton act, to use embryos when an uncontentious and superior alternative was available.

 

"If there is any medical value in learning to create sperm from stem cells – and there are some arguable uses – then this objective could have been met in an ethically uncontentious way: the sperm could equally well be created from non-embryonic stem cells. Indeed the Newcastle researchers are already working on creating sperm from iPS cells, without exploiting embryos: Time magazine reports that "Nayernia's group is now working on creating sperm from the skin cells of infertile men (the sperm cells in the current study were generated from embryos discarded by fertility clinics)"

 

"We know that iPS cells, derived from adult cells without ever using eggs or embryos, are the exact functional equivalent of ESCs. Anything an ESC can do, an iPS can do – with the further advantage that iPS exactly matches the patient. The sperm created from embryos are that embryo's sperm. The sperm created from an iPS cell are the sperm of the adult whose skin cell was transformed into an iPS cell, and then into sperm.

 

"One valid medical application of sperm-from-stem-cells would be to enable infertile men – perhaps victims of mumps in childhood, or cancer treatment as young adults – to regenerate their own sperm from their own iPS cells. When this is done with iPS cells from the man himself, that avoids the exploitation of an embryo, and keeps the relationship of father-mother-child intact, since the sperm cells would indeed be derived to the patient himself.

 

"Incredibly, the Newcastle scientists suggest that SCNT cloning is the way to go to achieve genetically-matched stem-cell-sperm for an infertile man.

 

"But it would be scientific (and financial) folly to attempt to clone a patient into his twin embryo, in order to extract its stem cells – a task that has never been achieved - and turn them into sperm cells, when one could simply scrape his skin and turn those cells directly into pluripotent iPS cells – a task that is routinely achieved - and thereby into genetically-matched sperm.

 

"The abuses of embryonic stem cell science must be ended now that we have, in iPS, a scientifically and ethically superior alternative. I look forward to the Newcastle group's paper showing the creation of sperm from iPS cells, not embryos", Dr van Gend concluded.            ENDS.

Watch this show! ABC TV ‘gets it’ re the iPS revolution

http://www.abc.net.au/catalyst/stories/2608076.htm

Last night we saw that rarest thing: a nearly-accurate presentation of stem cell science on television. At last, the popular programmes – from Oprah in the US, to this more serious show, Catalyst, in Australia – are getting the message right (and maybe without even reading this Blog…):

"You are about to witness what the Science journal described as 'breakthrough of the year'. Where stem cells are created from ordinary adult cells, without the use of eggs or embryos."

There is first a detour through the history of ESCs – where they politely avoid the issue of tumour formation, but do refer to the immune-rejection problem - and then a reference to ASCs – where the weary old fallacy shows up (that lacking pluripotency is a disadvantage of ASC – whereas, as we know, it is a curse to be pluripotent: it makes you a dangerous, tumour-forming nuisance). These supposedly less useful 'multipotent' ASCs are shown, in another segment of the show, being use as therapy for damaged cartilage – in both a horse and a patient. No tumours there! All good. See http://www.abc.net.au/catalyst/stories/2608197.htm Noticeable by their absence from any actual therapies are those little ESCs which are supposedly so much more 'potent'… Hey ho…

Next, the story returns to the Gee-Wizz headline about the iPS revolution:

"And in 2008, scientists did that successfully with human cells. They're called Induced Pluripotent Stem Cells, or iPS cells. Now in theory, any cell in our body can become like an embryonic stem cell. … Researchers are still figuring out how this amazing transformation takes place. Put simply you start with an adult cell, say a skin cell. You then insert four genes into the cell, the kind of genes responsible for regulating the cells development. And that effectively reprograms the cell, wipes the slate clean and sends it back to the embryonic state. You can then direct it to become any cell you like, say a heart cell."

Enter Prof Bob Williamson. This is the same scientist, spokesman for the AAS on cloning, who brought you the most offensive furphy in the early stages of the cloning debate – that cloning does not really create a human embryo (he called it an 'intermediate cellular product', as I recall). That argument was designed to remove the moral sting from cloning, since if it does not create a living human embryo, what is the big fuss? But eventually even Loane Skene of the Lockhart Committee admitted that – as with Dolly the sheep – SCNT cloning does indeed create a human embryo, which could, in theory, be born as a baby.

Interviewed for last night's show, the Professor appeared to be on song with the South Australian scientists who recently tried to denigrate iPS to MPs: try to smear iPS as being somehow uniquely 'dangerous', and therefore make the case (as in SA) that 'we still need to do cloning and ESC research…'

Here it is:

"But Bob Williamson urges we proceed with caution before injecting genetically modified IPS cells into people.
PROF. BOB WILLIAMSON:
"Obviously we have to know whether IPS cells can cause cancer or not and we don't even know that with certainty."

Cancer! Injecting cancer-causing cells into people! That gives iPS a real 'danger' label. Smart politics, but not a scientifically transparent statement of the equivalence, in terms of any 'dangers', of the new iPS and the old ESC. No, what a scientist in Prof Williamson's position might have explained to the viewer is this:

"Obviously we would never inject iPS cells into people any more than we would inject ESC into people. You can't do that, as they both form tumours. We can only inject ASCs into people. What we can do with ESC and iPS cells is study genetic disease and develop drugs against those diseases. And of course, dear viewer, any useful research an ESC could do an iPS can also do - because they are functionally identical cells. Indeed, the iPS is superior because it is an exact genetic match of the patient, while an ESC could only be a genetic match if one first clones the patient into an embryo, in order to destroy it for its stem cells… What sort of mug science is that, undertaking the ethically contentious, enormously expensive and technically difficult (indeed impossible, so far) act of SCNT cloning for stem cells, when you can so easily obtain the exact same research cells by scratching off a bit of skin?"

And then we have another worried comment from the Professor, this time on the troubling ethics (I jest not) of iPS: "the idea that every cell in your body has the potential to become an embryo, is itself a slightly scary thought". In the context of this TV story, his comment is another subliminal message of caution about these worrying little iPS cells - and it is a load of nonsense. There is only one cell in anyone's body that can 'become an embryo' and that is the oocyte. The woman's egg alone has the totipotency (that's one up on pluripotency) to 'become an embryo' once fertilised (or once tricked by cloning into 'thinking' it's been fertilised). Other cells can provide the nuclear DNA for SCNT cloning, and thereby act as a bogus 'sperm' - but they lack the cellular machinery for forming the whole show - placenta and embryo together. Prof Williamson is mistaken; no other cell in the body can ever develop into an embryo. Therefore his ethical suggestion that 'any cell' is now, since iPS, somehow morally equivalent to an embryo is misguided. It harkens back to his original attempt to degrade the true embryo created by cloning - to the status of an 'intermediate cellular product'; this time the moral equivalence smear is to upgrade 'any cell in our body' to the moral status of a potential embryo, and therefore remove the 'specialness' of the embryo.

Very disappointing spin coming from an honest scientist.

We can look forward to plenty more muddying of the waters by embryo-research advocates as we head into the cloning review next year. Yet shows like the ABC Catalyst of 25^th June 2009 show that the truth of the redundancy of embryo experimentation is going to be harder to obscure behind scientific smokescreens.

Dr Margaret Somerville: why embryo experimentation is wrong – and unnecessary

Another pithy summary of the arguments for and against ESC research – from a professional ethicist (of Australian origin).

Well worth a read for those who want to think like an adult, not like a sound-bite-juvenile.

 

First, why embryo experimentation is wrong:

"We are all ex-embryos and are all in the process of becoming, from conception to death… Human embryo stem cell research kills embryos and destroys that potential. The central ethical issue it raises is: What does the value of respect for human life require that we not do to human embryos?"

 

And later, why embryo experimentation is redundant:

"As mentioned already, there are now ethically uncontroversial alternatives for obtaining pluripotent stem cells -- iPS technology. This is an example of science being able to solve ethical problems rather than creating them… Stem cells can also be obtained from umbilical cord blood or consenting adults. So far somewhere around 200 therapies have been developed from these ethically uncontroversial alternatives, while none have yet come from embryo stem cells."

 

But that snapshot does no justice to such an elegant, if brief, review of the subject. For the full article, pick up a copy of the Ottawa Citizen from the 22^nd June – or click here: http://www.ottawacitizen.com/Technology/Destroying+life+science/1719495/story.html

 

 

Caplan Capitulates on Cloning…

Hidden here in the Scientist Blog from Thursday 17^th is another 'moment of truth' – this time from the noted bioethicist and not-usual-suspect, Arthur Caplan: "the odds are that cloning for research is never going to work".

Sweet on the ear. And scientifically correct. Cloning has been dead in the water at least since November 2007, despite the millions of dollars expended since then, and the dozens of desecrated human offspring. Nobody has managed to get a cloned human embryo to live long enough to form its inner cell mass of stem cells – those magic 'patient-matched' pluripotent stem cells that justified cloning in the first place. Meantime, the exact same patient-matched pluripotent stem cells have now been produced easily, cheaply, and surely by iPS direct reprogramming. Already we have hundreds of such stem cell lines up and running. Cloning, ladies and gents, is withering on the vine and will soon become mere pseudo-scientific compost…

Yet still the embryo lobby acts as if drunk on this rotting fruit, lurching around, refusing to admit that there is a better, less contentious science at hand.

Sadly, the mere ethical objection against creating living human embryos for the sole purpose of destroying them will never cause them to sober up. The only motives for them to kick their cloning habit will be the gangbuster success of the alternative, iPS, and the prospect of litigation from women injured in obtaining the necessary thousands of eggs for these experiments.

This prospect of obtaining more eggs from women is the subject of debate in this Scientist blog. New York State has now broken another rule of ethical research by proposing to buy eggs from (predictably poor) women – a decision reached following, of course, 'extensive deliberation' from its obliging ethics team.

Two issues: the possible exploitation of the poor by making women's ovaries a tradable commodity:

Many critics, including Father Thomas Berg, director of the Catholic think tank Westchester Institute for Ethics & the Human Person, argue that compensation will lead to the exploitation of poor and disenfranchised women. Paying women as much as $10,000 -- the upper limit under the ESSCB's directives -- will "create an undue inducement" that will put vulnerable women at risk, he said. "It's precedent setting."

Second issue, whether obtaining eggs for SCNT cloning is even justified scientifically. Enter Caplan:

"I don't think it's a good idea," Arthur Caplan, a bioethicist at the University of Pennsylvania, told The Scientist.

It's "more ethically acceptable" to pay women to harvest eggs for in vitro fertilization programs because donor eggs have proven successful in assisted fertility treatments. With stem cell research, "the risk benefit ratio starts to slide," Caplan said. "It's a lot iffier a proposition and I think that makes a difference. In research you don't know what you're going to get, and the odds are that cloning for research is never going to work."

Of course, others continue to urge the need for women's eggs. The bioethicist for Advanced Cell Technology (ACT), a keen cloning company, speaks for the affirmative:

Ronald M. Green, a bioethicist at Dartmouth College in New Hampshire, said he's "glad to see" the ESSCB's decision. Green, who serves pro bono on the ethics advisory board of Advanced Cell Technology, a Massachusetts-based biotech company, said that it's ethical and necessary to pay women to donate eggs for stem cell research if researchers want to investigate the potential of therapeutic cloning.

ACT is especially clear on the need for human eggs, given their recent publication showing that the animal option – rabbit or pig eggs, for instance – is an utter failure. See the Blog on 'More nails in cloning's coffin: Frankenbunny RIP'.

Here, then, is the story on the latest desperate move by 'progressives' to shore up the crumbling edifice of SCNT cloning. Too late, and not worth the trouble, I am glad to say…

http://www.the-scientist.com/blog/display/55766/

The Scientist: NewsBlog: NY to pay for eggs for research - 17th June 2009

Smart private money backs adult stem cells

From this week's FORTUNE magazine, the rich people's rag, another greenshoot of commonsense on stem cell science.

We have already have seen that notably rich man, Al Gore, invest many of his own millions in iPS. And we heard some sound advice to Mum and Dad investors on the Oprah episode where that notable salesman for embryo experimentation, Michael J Fox, had his portfolio priorities trashed by Dr Oz.

Now another confirmation that smart money, if not serious ethics, will be the one to give the thumbs down to embryonic 'therapies' and get on with the serious business of using iPS and ASCs. Only dumb public money (as per Obama) will continue to be squandered on desecrating embryos.

Note the standard journalistic trope about embryo cells being possibly more useful for treatments in the long-term... that is a mindless mantra which readers of this Blog could demolish in a few short sharp blows:

1. You can never use ESCs as treatment, since they form tumours (unlike safe ASCs);

2. If you only want to derive secondary cells as 'treatment' (as per Geron Corp) then you would always do better to use iPS cells as the 'factory cells', as they are genetic matches - whereas ESCs are not;

3. smart money says the default position is always to use cheap and simple iPS cells, as they are easy to obtain, superior as research material, and ethically non-contentious...

No, the journos will someday realise how vacuous their comments are about ESCs, which remain inferior in every way to iPS - let alone to ASC.

Adult stem cells are a promising market
Amid controversies over embryonic stem cell research, drugs using adult
cells are already bearing fruit.

By Anna Kattan, contributor
Last Updated: June 16, 2009: 11:03 AM ET
http://money.cnn.com/2009/06/16/technology/adult_stem_cell_therapy.fortune/index.htm

NEW YORK (Fortune) -- When it comes to stem cells, the public -- and the
media -- tend to focus on embryos. But researchers and analysts say
marketable therapies already are emerging from less controversial work
with adult stem cells.

Adult cells make up the lion's share of the stem cell space, mainly
because they are easier to come by than embryonic cells, and less expensive to
run in clinical trials. They are also derived from mature tissue, like bone
marrow or umbilical cord blood, so they avoid the ethical debate that
surrounds embryonic stem cells.

To be sure, many researchers consider embryonic stem cells to be more
versatile, and they may someday be more useful than adult stem cells in
treating diseases. But researchers also hope adult stem cells can help
them combat a variety of maladies from diabetes to heart disease.

In fact, adult stem cells are currently the only type of stem cells used
in transplants to treat diseases, such as cancers like leukemia.

Furthermore, researchers are far closer to commercializing drugs based
on adult stem cells than any product based on embryonic stem cells.

Read the full article…

Adult stem cells repair corneal blindness

Here is a tidy NSW application of our ever-versatile adult stem cells.

 

Corneal regeneration in humans has been around for some years using adult stem cells, but here a simple contact lens is used as the vehicle for applying the stem cells to the damaged surface.

 

Safe, cheap, and obviously "non-controversial", as Loane Skene (of the Lockhart Committee on human cloning and embryo research) points out.

 

To use cloning or embryos to obtain stem cells would not only be controversial, it would be plain stupid – as the cells are so second-rate: lacking the perfect immune match of our own stem cells, and likely to provoke tumours (and of course the exact same concern of tumours applies even to iPS cells).

 

Behold the future (and the present) of safe and effective stem-cell therapy: our own, simple, non-controversial cells.

Full story at: http://www.news.com.au/story/0,27574,25549740-36398,00.html

Excerpts:

COATING a common contact lens with stem cells could help restore a person's sight, Australian scientists have found.

University of New South Wales medical researchers used the technique to treat the damaged corneas of three patients, all of whose vision improved within weeks of the groundbreaking procedure. The results are published in the journal Transplant.

Stem cells were harvested from the eyes of each patient and then cultured inside a contact lens, which was then stuck onto a damaged cornea in a "transplant'' of regenerative cells.

"The procedure is totally simple and cheap,'' said the university's Dr Nick Di Girolamo. The procedure could be replicated in third would countries by a surgeon with a laboratory for cell culture, Dr Di Girolamo said.

It offered hope to people with a range of blinding eye conditions, he said, and there was also the possibility of adapting the technique to repair skin which behaved in a similar way to the eye.

The stem cell procedure was considered non-controversial, said former Deputy Chair of the Lockhart Committee on human cloning and embryo research Professor Loane Skene.

 

Read this! Wilmut, King of Cloning, says iPS has made cloning ‘no longer applicable’

A remarkable interview this month with Prof Ian Wilmut – who created the first cloned mammal in 1997, Dolly the sheep. Wilmut was the first senior scientist to signal the move away from cloning to 'induced pluripotent stem cells' (iPS cells) in November 2007 – see the report in the Telegraph, "Dolly Creator Ian Wilmut shuns cloning". This new interview shows again that the true shape of stem cell science is now acknowledged even by former advocates of cloning - and cannot be suppressed in the way it was during recent Parliamentary debates.

 

Browse the comments by Wilmut, and note that they exactly match what honest scientists – including this association – have been trying to get through to journalists and MPs since the iPS cell revolution of November 2007 – namely that the one justification that carried the vote for cloning is now dead and gone, and there is no longer any defence for this inhuman science:

• iPS cells have achieved the exact goal that cloning hoped to achieve (but never has achieved) – namely, patient-matched pluripotent stem cells:
  
  • "Before the discovery of iPS cells, we were trying to derive embryo stem cells produced by nuclear transfer from the cell of a patient who suffered an inherited disease. So far, nobody has been successful. But then, reprogramming somatic cells from mice (Yamanaka's method) demonstrated that the same objective could be achieved directly using somatic cells from patients."
    
    
• iPS is up and running now, already being used in research, whereas EScell research from cloning has never even started – and now has lost its justification:
  
  • "People do not yet realize that studying inherited diseases on cells obtained by reprogramming is much easier and faster than getting human embryonic stem cells by cloning. The iPS technique to obtain stem cells is now the most efficient technique for researchers, in particular for research on inherited diseases."
    

    
     

• Contrary to the claims of the embryo-research lobby, we never really needed to experiment on human embryos to obtain this new, ethical stem cell science of iPS; Yamanaka has never touched a human egg or human embryo:
  
  • "The de-differentiation of somatic cells didn't require the use of human embryos as, technically speaking, it wasn't necessary. The first iPS cells were produced and identified through studies on mouse embryos."
    

The French interview is at http://www.genethique.org/tribunes_mensuelles/mai_2009.asp

 

For the sake of non-French readers, here is the full English translation:

 

Gènéthique Interview with Prof. Ian WILMUT, May 2009:
Chair of Reproductive Biology at the Medical Research Council Centre for Regenerative Medicine in Edinburgh, Ian Wilmut was the first to succeed in cloning a mammal in 1997 – Dolly the sheep.

Is research on the embryo and cloning still necessary
since the discovery of iPS cells ?

 

1 - After the discovery by Prof S. Yamanaka and J. Thomson in November 2007 , you told the BBC that you gave up cloning in favour of iPS cells and that "within five years the new technique could provide a better and ethically more acceptable alternative to cloning embryos for medical research". Since 2007, what have been the advances in research with iPS cells, compared to the scientific expectations and goals you had in cloning Dolly ?

WILMUT: "Before the discovery of iPS cells, we were trying to derive embryo stem cells produced by nuclear transfer from the cell of a patient who suffered an inherited disease. So far, nobody has been successful. But then, reprogramming somatic cells from mice (Yamanaka's method) demonstrated that the same objective could be achieved directly using somatic cells from patients.

"The main therapeutic advantage with iPS cells is that they are genetically identical to the patient, they can be used for disease modelling and to look for drugs to prevent symptoms of the disease. There are already about a hundred cell lines on which it is possible to work right away, and which could help us to understand diseases within 5 years.

"Therefore, the technique of cloning is no longer applicable. As with my experiments with Dolly the sheep, cloning requires considerable time to obtain stem cells. Moreover, this technique asks women to undergo ovarian hyperstimulation: they will have to endure an intensive and unpleasant hormonal treatment in order to produce a high number of oocytes and still obtain only a low number of cloned embryos.

"If science can offer faster, more interesting and more efficient means, I want to use them.


2 - What are the scientific and therapeutic hopes with iPS cells? And what are the challenges for researchers ?

WILMUT: "Researchers working on iPS cells are trying to improve the quality of these cells. Their availability and capacities are unquestionable, but the technical challenge is to successfully reprogram cells without provoking collateral damage. It will take very little time to overcome these obstacles: recent scientific publications showed that it is already possible to reprogram differentiated cells using neither viral vectors nor plasmids.

"For economic reasons, I think it no longer possible to envisage creating personal stocks of iPS cells for each patient to look for treatments to their diseases. What would be more feasible from my point of view is to have a sort of registry, or Bio-Bank, where cell lines for different kind of immunological diseases would be listed. It would then be possible to modify and work on these cell lines according to the requirements of each patient.


3 - In France, it has been said that iPS cells were obtained thanks to human embryonic stem cells. However, Prof. Yamanaka's publications on human iPS cells were preceded by results on mouse cells . Could iPS cells have been discovered solely through research on animal models, without recourse to human embryonic stem cells?

WILMUT: "The de-differentiation of somatic cells didn't require the use of human embryos as, technically speaking, it wasn't necessary. The first iPS cells were produced and identified through studies on mouse embryos.

"People do not yet realize that studying inherited diseases on cells obtained by reprogramming is much easier and faster than getting human embryonic stem cells by cloning. The iPS technique to obtain stem cells is now the most efficient technique for researchers, in particular for research on inherited diseases.

"There is also research being done on human embryonic stem cells to better understand their differentiation and cultivation, because iPS cells share the properties of human embryonic cell lines.


4 - Research on iPS cells is accelerating in the USA and in Asia. How about in Europe ? Is there significant support for this research ?

WILMUT: "Research on iPS cells is supported in many European countries: British agencies such as the Biotechnology and Biological Sciences Research Council (BBSRC) are financing programs at the University of Edinburgh where I am currently working. In France too, interesting projects are underway with iPS.


5 - Is there more scientific interest in using human iPS cells than human embryonic stem cells to look for drugs, for (disease) modelling and for screening of pharmacological molecules ?

WILMUT: "Yes. iPS cells are more useful than embryonic cells for this research because, if you take reprogrammed cells from a patient who has an inherited disease you want to study, the advantage is that these cells already carry the characteristics of that person. You do not have to introduce a genetic error. There are many inherited diseases for which we do not yet understand the molecular basis."