Stem cells through the lens of the Korean cloning scandal

Stem cells through the lens of the Korean cloning scandal

A lens through which to view general issues of stem cell

research

• Promise of embryonic stem cells to cure disease and as a driver of a medical industry

• Ethical pitfalls• Difficulty of the technique• Policy implications for Australia

Skin cell, limited proliferation

Skin stem cell (adult stem cells), proliferates but only makes skin cells

Stem cells 101

Embryonic stem cells proliferate indefinitely and make all tissues

BIOLOGICAL GOLD!!!!

Making embryonic stem cells

BUT SOME TISSUES ARE MORE DIFFICULT THAN OTHERS

MOST DIFFICULT

DONE DONE DONE

A LONG WAY TO GO

• TRAIN CELLS TO MAKE SPECIFIC TISSUES

• ELIMINATE CANCER CELLS

• GRAFT REJECTION???

• THERAPEUTIC CLONING PROVIDES MATCHED TISSUES, HENCE THE GREAT PROMISE

Cattle cloning: about 10% success rate

In Feb 2004, Hwang announces first success

But it was a very qualified success:

1. Couldn't prove it was a clone

2. Only cumulus cell

3. Only if from same egg and nucleus donor?

4. 242 eggs!

Cumulus cell

Woo Suk Hwang’s group dazzle the world

May 2005: it’s a go-er!

-Cloned from skin cells of men, women and children

-increased success rate over 10 fold (17 eggs per cell line), practiced with cow eggs!

Astonishing that no-one suspected

• Korean work ethic 24/7

• Supportive policy and funding

• Technical prowess borne of lifetime’s use of steel chopsticks

Scientific smoking guns

• Proofs that they were embryonic stem cells: visual appearance, marker proteins, teratomas

Marker proteins look good

Teratomas for three of the cell lines

Spot the duplication?

Are they cloned stem cells?

• Compare DNA fingerprints of donor skin cells and stem cell lines

DNA Fingerprints

Policy implications

• Women were exploited (suffered side-effects; some did it for money)

• Scientists behaved dishonestly (now also an issue of missing millions)

• Ban the technique?

Legislation that permits advance while preventing transgressions

• TC will not be used to produce customized tissues—its too hard

• For model diseases its still a worthy goal

One in 8000 births, biggest genetic killer of kids under 2 yo

Disease causes death of motor neurons

Use Therapeutic cloning to make cell lines for screening drugs

Spinal Muscular Atrophy-a case in point

Put cloned cells to work tomorrowMany diseases a mystery: genes and environmentALS: 95% out of the blue, MN die offNo real animal models Cloned cells from patients could be first real models to study the disease ES cells (not adult stem cells) can be made into Motor Neurons (H. Wychterle 2002, Cell)

Test 100,000 compounds a day on these model patients

Unscientific debate

• “Pick and choose” notions of research are misguided

• Furfies — adult stem cells have more runs on the board. Only in bone marrow transplants and skin grafts

• Novel applications remain unproven and highly contentious.

Common sense: in exploration success comes from following as many paths as possible