有人知道更多的信息么? http://www.lifesitenews.com/news/breakthrough-new-heart-grown-u Breakthrough: New heart grown using adult stem cells by Hilary White Mon Apr 04, 2011 16:05 EST Comments (1) Tags: stem cells April 4, 2011 (LifeSiteNews.com) – Researchers at the University of Minnesota used adult stem cells to create a living human heart that they hope will revolutionize transplants. The breakthrough, said lead researcher Dr. Doris Taylor, could ultimately mean that “donated” hearts are no longer used in transplant operations, circumventing the ethical problems involved in organ donation and obviating the need for drugs to combat immune system rejection. Dr. Taylor, director of the university’s Center for Cardiovascular Repair, is one of the world’s leaders in heart organ repair and regeneration and has said it is her goal to create a living heart that can be transplanted into a patient, entirely out of stem cells. She presented her team’s findings at the American College of Cardiology’s annual conference in New Orleans. “The hearts are growing, and we hope they will show signs of beating within the next weeks,” she told the Daily Mail. “There are many hurdles to overcome to generate a fully functioning heart, but my prediction is that it may one day be possible to grow entire organs for transplant.” The breakthrough is a follow-up on work Dr. Taylor completed in 2008 in which her team used stem cells to rebuild the hearts of rats. They removed all the muscle cells in a rat heart, leaving just a “scaffold” of other tissues such as blood vessels and valves. This scaffold was then repopulated with stem cells, which took their cues from the scaffold tissue to regenerate healthy, functioning heart muscle. The latest step in Dr. Taylor’s research took that theme one step further and removed the muscle cells from a heart obtained from a human donor, regrowing the muscle using stem cells taken from a second person. The researchers say that a heart taken from a pig may also be suitable. The muscle cells are removed using detergents, leaving an extracellular matrix or “skeleton.” The stem cells used this skeleton to grow millions of new heart cells and create heart muscle tissue. “We are a long way off creating a heart for transplant, but we think we’ve opened a door to building any organ for human transplant,” she said. A similar technique was used in March last year to create a new trachea for a ten year-old boy. In related news, a team of researchers at the University of Miami has shown that damaged heart tissue can be repaired by injecting the patient’s own stem cells directly into the heart. In the experiment, published in the March edition of the Journal of the American College of Cardiology, donated stem cells were injected into the hearts of eight male volunteers who suffer from chronically enlarged, low-functioning hearts. The Miami researchers have already documented a significant reduction in size, scar tissue, and a notable improvement in heart function. The creation of whole working organs for transplant is the “Holy Grail” of stem cell research. Stem cells that have been used in this research and in some current disease treatments have been taken from patients’ skin, bone marrow, fat, teeth and blood.
They said they only remove cardiomyocytes, which means blood vessels ( endothelial cells and smooth muscle cells), valve (endothelial cells) and structure (fibroblast) of the heart are fine. But I did not hear the talk and not sure how they did it. In Zebrafish, scientist use a genetic tool to kill 90% of the cardiomyocytes , and the heart still can regenerate.
【在 m*p 的大作中提到】 : They said they only remove cardiomyocytes, which means blood vessels ( : endothelial cells and smooth muscle cells), valve (endothelial cells) and : structure (fibroblast) of the heart are fine. But I did not hear the talk : and not sure how they did it. : In Zebrafish, scientist use a genetic tool to kill 90% of the cardiomyocytes : , and the heart still can regenerate.
they called the method " whole organ decellularization", same as the paper about lung. how do you guys think the detergent could specifically "wash out" the myocardial cells but not endothelial cells and smooth muscle cells ? the news should be written by some layman and is misleading for this point.
I don't worry about the angiogenesis problem but I am curious what kind of stem cell they use? They said they are the adult stem cells.. so are they the MSCs or cardiac stem cells? And also when the stem cell differentiate into the cardiomyocyctes, will they beat regularly and have the normal cardiac function?
【在 L**********O 的大作中提到】 : I don't worry about the angiogenesis problem but I am curious what kind of : stem cell they use? They said they are the adult stem cells.. so are they : the MSCs or cardiac stem cells? And also when the stem cell differentiate : into the cardiomyocyctes, will they beat regularly and have the normal : cardiac function? : : 分化 : 印象
I read a little background, yes, they kill every cells in the heart, leaving ECM behind. They argue ECM in the heart and artificial pressure mimicking the blood flow can drive the stem cell to differentiate to endothelial cell and smooth muscle cells, but I did not read the paper and did not know how they demonstrate the "heart" has all the cells. By the way, the heart has an artificial PACE MAKER to initiate the heart beating. In the zebrafish, they use a cardiomyocyte specific promoter to drive a toxic gene in cardiomyocyte and kill majority of the cardiomyocytes, and the heart still can be regenerated. It is a quite different story.
Yes, it is misleading, the news says killing muscle cells, but actually they kill all the cells, and only ECM all the heart frame is there.
paper
【在 x**w 的大作中提到】 : they called the method " whole organ decellularization", same as the paper : about lung. : how do you guys think the detergent could specifically "wash out" the : myocardial cells but not endothelial cells and smooth muscle cells ? : the news should be written by some layman and is misleading for this point.
After decellularization, only ECM is there, The ECM may function as a niche to cheat the stem cell to differentiate to blood vessels, with the help of artificial blood flow, as the Senior author said. It is still far away. I did not see the paper, except news.
The hard part is the interface between cells and machines. it's very very hard, the biggest problem is whatever material you put into the cells, the cells will try to eliminate it, engulf it, xxxx it, etc, the by the time your machine will malfunction. So long term maintenance seems too hard. Which is why people start to use the native ECM materials to make artificial XXX, but native materials have other problems.
【在 d*****r 的大作中提到】 : The hard part is the interface between cells and machines. : it's very very hard, the biggest problem is whatever material you put : into the cells, the cells will try to eliminate it, engulf it, xxxx it, : etc, the by the time your machine will malfunction. So long term : maintenance seems too hard. Which is why people start to use the native : ECM materials to make artificial XXX, but native materials have other : problems.
a*g
86 楼
但是要加钱啊
【在 q********m 的大作中提到】 : 栏杆好看点
e*s
87 楼
圣诞快乐!
d*r
88 楼
of course it depends on how deep the integration you want.
这么听起来很奇怪啊,好像和那个新闻里讲的不相符, 新闻里说的是 They removed all the muscle cells in a rat heart, leaving just a “scaffold” of other tissues such as blood vessels and valves. 不知道是不是那个记者写错了。 不过,假如他们能够特异性在体外的用化学/物理方法除去心肌细胞而不影响其他 细胞的话也够令人惊讶的了。我倾向认为是那个记者写错了。
leaving ECM behind. They argue ECM in the cell to differentiate to endothelial cell they demonstrate the "heart" initiate the heart beating. toxic gene in cardiomyocyte and kill is a quite different story.
【在 m*p 的大作中提到】 : After decellularization, only ECM is there, The ECM may function as a niche : to cheat the stem cell to : differentiate to blood vessels, with the help of artificial blood flow, as : the Senior author said. It is still far away. : I did not see the paper, except news.
I watched one of the senior author's interviews, and she means all the cells were removed.我认为是那个记者写错 了. Actually, heart and vessels have abundant of ECM, and I think the "heart frame" or the "scaffold" is the ECM. Some people say about 75% of the cells in the heart are fibroblasts, although their volume contributes to only 15% of the heart, and the fibroblasts secret lots of ECM, and if fibrosis happens, there will be even more ECM. That might explain why all cells were removed, but there is a heart scaffold .
just
【在 s******y 的大作中提到】 : 这么听起来很奇怪啊,好像和那个新闻里讲的不相符, : 新闻里说的是 They removed all the muscle cells in a rat heart, leaving just : a “scaffold” of other tissues such as blood vessels and valves. : 不知道是不是那个记者写错了。 : 不过,假如他们能够特异性在体外的用化学/物理方法除去心肌细胞而不影响其他 : 细胞的话也够令人惊讶的了。我倾向认为是那个记者写错了。 : : leaving ECM behind. They argue ECM in the : cell to differentiate to endothelial cell : they demonstrate the "heart"
【在 m*p 的大作中提到】 : I watched one of the senior author's interviews, and she means all the cells : were removed.我认为是那个记者写错 : 了. : Actually, heart and vessels have abundant of ECM, and I think the "heart : frame" or the "scaffold" is the ECM. : Some people say about 75% of the cells in the heart are fibroblasts, : although their volume contributes to only : 15% of the heart, and the fibroblasts secret lots of ECM, and if fibrosis : happens, there will be even more ECM. : That might explain why all cells were removed, but there is a heart scaffold