Site author Richard Steane
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Cloning of human body parts for transplant surgery
Artificial bladder (3 layers of cells on a biodegradable scaffold), and an artificial windpipe
No - this is not what is meant by cloning of human body parts for transplant surgery, although some people distrust scientists enough to believe that this is so!
In fact it is just an experiment to see if cells can be encouraged to grow on a preformed structure. Admittedly the mouse is a rather strange hairless variety, but would you like an ear covered with mouse hair?
In fact body parts cannot be directly cloned and grown. You cannot slice up, say, a kidney and expect it to grow into two or three new ones!
The most promising lines of approach involve encouraging stem cells to differentiate into specific cell types and then encouraging them to colonise 3-D templates so that they can take on the shape that is required. There has been some success with artificial or replacement bladders and windpipes.
Recent advances in 3-D printing offer the chance of building 3-D templates made from various chemical compounds, which may even degrade over time.
It is also worth noting that there have been high-profile failures and scandals with some of these approaches.
See web references below.
There are 5 main areas of transplant activity:
kidney, pancreas, cardiothoracic, liver, cornea.
The gap between the supply of and demand for organs for transplantation has widened from approximately one to two times the (fairly steady) supply figure. There appears to be only a limited likelihood of extra supply from volunteer donors, so it is hoped that some of this shortfall will be made up by material obtained from cloning techniques.
Transplant supply and demand data
This graph shows the difference between the need for transplant organs and the supply from deceased donors in the UK from 1997-2007.
Some questions about this information
What is the general trend shown by the need for transplant organs over the time period covered?
>gradual increase for the first few years (5248-5673), then more rapid increase recently (up to 7234)
What does the term deceased mean?
> dead - possibly following road traffic accidents or (sudden?) illness
What is the general trend shown by the number of deceased donors over the time period covered?
>very steady (range 738-796) - no real increase or decrease
What is the general relationship between the number of deceased donors and the number of organs transplanted over the time period covered?
>number of transplanted organs is about 2-3 x as many as number of donors
How would you explain this?
>Each donor gives both kidneys and possibly other organs
Update -things are looking up!
The eagle-eyed amongst you will spot minor differences between start values here and end values above.
Now what is the general trend shown by the need for transplant organs over the time period covered?
>continues to increase for the first three years (7224-8012), then decreases steadily (down to 6476)
Now what is the general trend shown by the number of deceased donors over the time period covered?
>gradual increase (range 793-1354)
How would you explain this trend ?
>No - it is not that more people are dying [dying to be donors?],
but more people have expressed the wish to donate their organs for transplantation
Great Moments in science : Mouse with Human Ear
Artificial liver 'could be grown'- BBC news story
The organ factory of the future? -
A New Scientist archive article dating back to 18 June 1994
How it is done; possible benefits
- quite a balanced article from Ontario Consultants on Religious Tolerance
Organ Donation and Transplantation -
Activity figures for the UK as at 8 April 2016
Organ Donation and Transplantation Activity Report 2015/16
Windpipe transplant breakthrough - Scientists (including surgeon Paolo Macchiarini) have carried out the world's first tissue-engineered whole organ transplant made with a patient's own stem cells.
An informative article with good graphics.
But see the article in 'Controversies' below.
Doctors herald grow-your-own organs
-Internal organs grown in the laboratory have been successfully transplanted into animals for the first time.
"Six dogs received new bladders constructed in the laboratory from cells multiplied from small samples of their original bladders. "
Organ re-engineered for the first time in bladder transplants.
"The first complex organ, the bladder, has been rebuilt in seven patients from living tissue cultivated in the lab. "
New pig cloning research promising yet risky, studies indicate
Paolo Macchiarini: A surgeon's downfall
By William Kremer BBC World Service
The surgeon Paolo Macchiarini and the
Karolinska Institute(t) have been dragged into public scrutiny over transplants involving synthetic 3-D templates.
Stem cell scandal scientist Haruko Obokata resigns
Dr Haruko Obokata published supposedly groundbreaking research showing stem cells could be made quickly and cheaply, but this was eventually discredited, and articles published in Nature were retracted.
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