Gold9472
01-13-2008, 05:55 PM
Hopes of custom-built organs as scientists create beating heart
http://www.timesonline.co.uk/tol/news/uk/health/article3177646.ece
Sarah-Kate Templeton, Health Editor
1/13/2008
SCIENTISTS have created a beating heart in the laboratory in a breakthrough that could allow doctors one day to make a range of organs for transplant almost from scratch.
The procedure involved stripping all the existing cells from a dead heart so that only the protein “skeleton” that created its shape was left.
Then the skeleton was seeded with live “progenitor” cells, which multiplied and grew back over it, eventually linking together into a new organ. Such cells are involved in the formative stages of specialised types of tissue such as those found in the heart.
The research, by scientists at the University of Minnesota, has so far been done only with rats and pigs and is highly experimental. It is unlikely to be applied to humans for years.
However, Professor Doris Taylor, director of the university’s centre for cardiovascular repair, believes it could be a significant step towards creating custom-built hearts, blood vessels and other organs for people with serious illness.
The big advantage of such an approach is that organs so built would use stem cells taken from the patient so the body’s immune system would not reject them.
“The idea would be to develop transplantable blood vessels or whole organs that are made from your own cells,” Taylor said. “It opens a door to the notion that you can make any organ - kidney, liver or pancreas. You name it and we hope we can make it.”
Taylor and her colleagues used a process called decellularisation, in which powerful chemicals strip the cells from a dead animal heart. The researchers then reseeded the remaining protein skeleton with progenitor cells taken from the hearts of newborn animals and let them grow. Taylor said that four days after seeding, the cells could be seen contracting, and after eight days the hearts started contracting.
“We took nature’s building blocks to build a new organ,” said Harald Ott, who worked with Taylor. “When we saw the first contractions we were speechless.”
The new technique was reported at the American Heart Association’s recent annual meeting in Orlando, Florida. “This is a proof of concept,” Taylor said. “Going forward, our goal is to use a patient’s stem cells to build a new heart.”
- A new system of teams of surgeons working round the clock to retrieve kidneys and hearts from dead patients will be announced by a government body this week in an attempt to increase organ transplantation by 50% within five years.
The government’s organ donation taskforce will also announce the appointment of 100 more organ transplant co-ordinators, who will persuade relatives to agree to the organs of their deceased loved ones being used for transplantation.
It is also considering whether the government should introduce laws to allow organs to be taken from patients after death unless they have specifically expressed a wish not to donate their tissues.
Gordon Brown today signals his support for the policy of "presumed consent".
Writing in a Sunday newspaper the prime minister says: "A system of this kind seems to have the potential to close the aching gap between the potential benefits of transplant surgery in the UK and the limits imposed by our current system of consent."
Sir Liam Donaldson, England's chief medical officer, who also supports the policy, said: "We have one of the lowest rates [of organ donation] in Europe."
http://www.timesonline.co.uk/tol/news/uk/health/article3177646.ece
Sarah-Kate Templeton, Health Editor
1/13/2008
SCIENTISTS have created a beating heart in the laboratory in a breakthrough that could allow doctors one day to make a range of organs for transplant almost from scratch.
The procedure involved stripping all the existing cells from a dead heart so that only the protein “skeleton” that created its shape was left.
Then the skeleton was seeded with live “progenitor” cells, which multiplied and grew back over it, eventually linking together into a new organ. Such cells are involved in the formative stages of specialised types of tissue such as those found in the heart.
The research, by scientists at the University of Minnesota, has so far been done only with rats and pigs and is highly experimental. It is unlikely to be applied to humans for years.
However, Professor Doris Taylor, director of the university’s centre for cardiovascular repair, believes it could be a significant step towards creating custom-built hearts, blood vessels and other organs for people with serious illness.
The big advantage of such an approach is that organs so built would use stem cells taken from the patient so the body’s immune system would not reject them.
“The idea would be to develop transplantable blood vessels or whole organs that are made from your own cells,” Taylor said. “It opens a door to the notion that you can make any organ - kidney, liver or pancreas. You name it and we hope we can make it.”
Taylor and her colleagues used a process called decellularisation, in which powerful chemicals strip the cells from a dead animal heart. The researchers then reseeded the remaining protein skeleton with progenitor cells taken from the hearts of newborn animals and let them grow. Taylor said that four days after seeding, the cells could be seen contracting, and after eight days the hearts started contracting.
“We took nature’s building blocks to build a new organ,” said Harald Ott, who worked with Taylor. “When we saw the first contractions we were speechless.”
The new technique was reported at the American Heart Association’s recent annual meeting in Orlando, Florida. “This is a proof of concept,” Taylor said. “Going forward, our goal is to use a patient’s stem cells to build a new heart.”
- A new system of teams of surgeons working round the clock to retrieve kidneys and hearts from dead patients will be announced by a government body this week in an attempt to increase organ transplantation by 50% within five years.
The government’s organ donation taskforce will also announce the appointment of 100 more organ transplant co-ordinators, who will persuade relatives to agree to the organs of their deceased loved ones being used for transplantation.
It is also considering whether the government should introduce laws to allow organs to be taken from patients after death unless they have specifically expressed a wish not to donate their tissues.
Gordon Brown today signals his support for the policy of "presumed consent".
Writing in a Sunday newspaper the prime minister says: "A system of this kind seems to have the potential to close the aching gap between the potential benefits of transplant surgery in the UK and the limits imposed by our current system of consent."
Sir Liam Donaldson, England's chief medical officer, who also supports the policy, said: "We have one of the lowest rates [of organ donation] in Europe."