Monday, September 04, 2006

MEMO TO MAL: 'TOTIPOTENCY' IS THE CURSE OF EMBRYO STEM CELLS, NOT THEIR CROWNING GLORY

Today MPs in Canberra heard from leading Adult Stem Cell Researcher Alan Mackay-Sim the great news that privileged readers of this Blog have been hearing from the start – that adult stem cells can indeed do everything that embryonic stem cells from a cloned embryo dream of doing – but better.

ABC Radio PM: Do you believe that adult stem cells can do everything that therapeutic cloning potentially could do to establish treatments?
ALAN MACKAY-SIM: I think ... yes I do agree with that.”

Ah, but what about ‘totipotency’ said a very excited Dr Mal Washer.

“MAL WASHER: What Alan said, and I think this is an important thing, is that adult stem cells do not have totipotency. They have some flexibility and that is fabulous and maybe they'll get more flexibility with more research and time. But nothing can replace that total, every cell line in your body creation from an embryonic stem cell and no-one has said anything contrary to that there.”

Dr Washer, you will fool some of the people some of the time with your pseudoscientific bluster – but just between colleagues, what’s your game?

You know and I know that ‘totipotency’ – the ability to turn into ‘all’ tissues of the human body – is the central insurmountable problem with embryonic stem cells (ESCs). That is why these cells turn into tumours from every layer of the human body – because they are cursed with ‘totipotency’. Nobody will contradict your claims of totipotency for ESCs – but who wants totipotency anyway?

After all, the job description of an embryonic stem cell is to turn into all cell types – and in forming tumours it is only doing its job. By contrast, the job description of an adult stem cell is to be the repair kit for a certain tissue – and to turn into other tissues in only a very controlled manner (as Mackay Sim’s team has so beautifully demonstrated in their published work).

In the treatment of disease, which cell would you want in your body? One that is exploding uncontrollably into tumours, or one that is calm and controllable in turning into the desired cell type?

That is why there has never been a single embryonic stem cell implanted in a single human ever – they are too dangerous even in animals – while adult stem cells are now used safely in over 70 human diseases. For instance, the trial of ESCs in repairing the cartilage of mice – where a tumour was formed in every single joint injected. Compare this to the ongoing human trials of adult stem cells for the repair of cartilage. No tumours! Or the Bjorklund study using ESCs to treat Parkinson’s in rats, where one in five of the rats died of brain tumours from the ESCs.[i] Compare that to Mackay-Sim’s Griffith colleagues who have treated Parkinsons in rats using adult stem cells, without a single tumour, and with sufficient success to justify primate trials.

Happy patients versus sad rodents. That about sums it up.

Yet Washer has the chutzpah to declare that this curse of ‘totipotency’ is in fact what gives cloning for stem cells the edge over adult stem cells!!

This medically bogus hogwash, Mal, does no credit to your former profession.

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[i] Researchers injected Parkinson’s rats with mouse embryonic stem cells. The rats showed a modest benefit for just over 50% of the rats, but one-fifth (20%) of the rats died of brain tumors caused by the embryonic stem cells. Bjorklund LM et al.; “Embryonic stem cells develop into functional dopaminergic neurons after transplantation in a Parkinson rat model”; Proc. Natl. Acad. Sci. 99, 2344-2349, February 19, 2002

1 comment:

Anonymous said...

Dear Doctor,
Your contribution to this issue is immeasurable, clarifying the techniques the ESC advocates are promoting and in particular exposing the biases of the Lockhart Committee.

The DO No Harm site is excellent and I particularly appreciate the summary of the various issues it features.

All lucidly put and very well set out enabling many like myself to make a contribution with letter writing and informing others.

Then there is your work directly informing politicians. Given the complexities (mainly promoted by the ESC advocates) I guess it is not surprising that the pollies seem so gullible.

You give me great hope and your work is greatly appreciated.