embryonic stem cell death
Posted 20 November 2007 - 04:07 PM
At least for the time being, says Dr. Douglas Melton, co-director of the Harvard Stem Cell Institute, embryonic stem cell research should continue, since it's not clear yet how robust and safe stem cell therapies from other methods might be. "My answer to that question comes from a different perspective," he says. "Not from a scientific or political one, but from a patient perspective. A patient doesn't care how we got there. They're suffering from a disease and want to get the therapies as fast as they can. Until this method produces cells that have fully normal behavior, and normal physiological behavior, we cannot eliminate any avenue of research."And again:
Other scientists said it's too early for the field to follow Wilmut's lead. Cloning embryos to produce stem cells remains too valuable as a research tool, Jaenisch said.
Dr. George Daley of the Harvard institute, who said his own lab has also achieved direct reprogramming of human cells, said it's not clear how long it will take to get around the cancer risk problem. Nor is it clear just how direct reprogramming works, or whether that approach mimics what happens in cloning, he noted.
So the cloning approach still has much to offer, he said.
Posted 06 December 2007 - 05:47 PM
Research reported this week by three different groups shows that normal skin cells can be reprogrammed to an embryonic state in mice. The race is now on to apply the surprisingly straightforward procedure to human cells.
If researchers succeed, it will make it relatively easy to produce cells that seem indistinguishable from embryonic stem cells, and that are genetically matched to individual patients. There are limits to how useful and safe these would be for therapeutic use in the near term, but they should quickly prove a boon in the lab.
GREAT news. Thanks for sharing this, popechild!
I had lunch last Sunday with a scientist who's leading a team of researchers at the University of Alabama-Birmingham (UAB) in an effort to translate some of the recent stem cell advances into practical applications, specifically targeting Sickle Cell Anemia. It was incredibly exciting to hear about some of the advances they've been making, but it's always hard to know as a non-scientist what it all means in the "real world." Lo and behold, today I go looking for any news on a paper he had said to be on the lookout for, and I find this:
Researchers Say New Stem Cell Technique Cures Sickle Cell in Mice (Newswise)
Researchers at UAB (University of Alabama at Birmingham), along with a team from the Whitehead Institute, report successfully treating sickle cell anemia in mouse models using induced pluripotent stem (iPS) cells, a new stem cell technique that uses skin cells and does not require embryos. The findings, published in Science Express Online on Dec. 6, are the first to actually use the iPS technique to treat disease in an animal model.
The iPS technique received widespread attention in November when two laboratories reported using the process to turn human skin cells into stem cells, cells which can then be induced to form any other type of cell. Scientists believe stem cells have great potential in treating a variety of human diseases.
“The UAB/Whitehead teams took skin cells from mouse models genetically engineered to have sickle cell disease and reprogrammed them into iPS cells by adding four genes to each cell,” said Tim M. Townes, Ph.D., professor and chair of the Department of Biochemistry and Molecular Genetics at UAB and co-senior author of the study. “The new genes remodeled the chromosomes that instruct a skin cell to be a skin cell, so that the cells revert to stem cells.”
The researchers then used a DNA fragment engineered by Townes’ laboratory in 2006 to correct the basic sickle mutation in the cells. The corrected iPS cells were then induced to become blood stem cells (capable of making any type of blood cell) and were transplanted back into the diseased mice.
“The new blood stem cells began to function properly, making normal red blood cells that did not sickle,” Townes said. “The animals showed no symptoms of the disease and did not reject the transplanted cells.”
I still am curious to see how big a deal this will be in the press, as the report was only published today, and I wouldn't have found it if I wasn't looking for it specifically. But let's just say if I had Sickle Cell Anemia, I would be very, VERY excited right now!
Oh, and here's the abstract of the report itself from the journal Science.
Posted 02 April 2008 - 03:13 PM
Interesting rationale, don'cha think?
A team has grown hybrid embryos after injecting human DNA into eggs taken from cows' ovaries, which had most of their genetic material removed.
The embryos survived for three days and are intended to provide a limitless supply of stem cells to develop therapies for diseases such as Alzheimer's, Parkinson's and spinal cord injuries, overcoming a worldwide shortfall in human embryos.
Dr Teija Peura, director of human embryonic stem cell laboratories at the Australian Stem Cell Centre, said somatic cell nuclear transfer (SCNT) had been done between animal species, but the "99 per cent human" embryos could boost research.
"If successful, they would provide an important additional research tool to help realisation of stem cell-based therapies for human diseases," Dr Peura said.
Sleep easy tonight, folks. Sleep easy.
Posted 02 December 2009 - 04:13 PM
lie #1â€” aSCs are equivalentâ€”even superior to eSCs.
lie #2â€” we are doing eSCR on the approved lines.
No one did HUMAN stem cell research of any sort until 2005 when Johns Hopkins solved the mouse feeder-cell contamination problem. When the â€śblessedâ€ť eSC lines were regrown, they were devolved and useless.
aSCR and eSCR are complimentary, not competitive. aSCs are useless for disease modelling and have insufficient telomere length to be useful for anti-senescense research.