In this case, they wanted to study a rare, inherited premature aging disorder called dyskeratosis congenita. The blood marrow disorder resembles the better-known aging disease progeria and causes premature graying, warped fingernails and other symptoms as well as a high risk of cancer.
One of the benefits of stem cells and iPS cells is that researchers can make them from a person with a disease and study that disease in the lab. Harvard’s Dr. George Daley and colleagues were making iPS cells from dyskeratosis congenita patients to do this (…)
New technique removes several hurdles in generating induced pluripotent stem (iPS) cells, smoothing the way for disease research and drug development.
Stem cells are ideal tools to understand disease and develop new treatments; however, they can be difficult to obtain in necessary quantities. In particular, generating induced pluripotent stem (iPS) cells can be an arduous task because reprogramming differentiated adult skin cells into iPS cells requires many steps and the efficiency is very low – researchers might end up with only a few iPS cells even if they started with a million skin cells.
“We identified several molecular barriers early in the reprogramming process and figured out how to remove them using miRNA,” said Tariq Rana, Ph.D., director of the RNA Biology program at Sanford-Burnham and senior author of the study. “This is significant because it will enhance our ability to use iPS cells to model diseases in the laboratory and search for new therapies.”
Researchers said on Sunday they had found a safer way to transform ordinary skin cells into powerful stem cells in a move that could eventually remove the need to use human embryos.
It is the first time that scientists have turned skin cells into induced pluripotent stem cells or iPS cells — which look and act like embryonic stem cells — without having to use viruses in the process.
The new method also allows for genes that are inserted to trigger cell reprogramming to be removed afterwards.
Stem cells are the body’s master cells, producing all the body’s tissues and organs.
Embryonic stem cells are the most powerful kind, as they have the potential to give rise to any tissue type. However, many people object to their use, making iPS cells an attractive alternative, provided they can be made safely.
Researchers have known for some time that ordinary skin cells can be transformed into iPS cells using a handful of genes.
But to get these genes into the cells they have had to use viruses, which integrate their own genetic material into the cells they infect. This can cause cancer.
The alternative approach, described in the online edition of the journal Nature by two teams of researchers from Britain and Canada, appears to avoid the risk of such abnormalities.
The researchers harnessed a little piece of DNA called a transposon — sometimes known as a “jumping gene” because of its ability to move around inside the genetic code — to carry four genes.
Cardiomyocytes, the workhorse cells that make up the beating heart, can now be made cheaply and abundantly in the laboratory.
A team of Wisconsin scientists describes a way to transform human stem cells — both embryonic and induced pluripotent stem cells — into the critical heart muscle cells by simple manipulation of one key developmental pathway. The technique promises a uniform, inexpensive and far more efficient alternative to the complex bath of serum or growth factors now used to nudge blank slate stem cells to become specialized heart cells.
“Our protocol is more efficient and robust,” explains Sean Palecek, the senior author of the new report and a University of Wisconsin-Madison professor of chemical and biological engineering. “We have been able to reliably generate greater than 80 percent cardiomyocytes in the final population while other methods produce about 30 percent cardiomyocytes with high batch-to-batch variability.”
The ability to make the key heart cells in abundance and in a precisely defined way is important because it shows the potential to make the production of large, uniform batches of cardiomyocytes routine, according to Palecek. The cells are in great demand for research, and increasingly for the high throughput screens used by the pharmaceutical industry to test drugs and potential drugs for toxic effects.
Scientists in Melbourne for the first time have created a human stem cell reserve in Australia using a technique that avoids destroying embryos, which was developed in Japan and the United States.
The team from the Monash medical research institute produced an induced pluripotent stem cell line (IpS) that acts like embryonic stem cells, but are derived from adult skin cells. The method used to reprogram adult stem cells developed last year in Japan and the United States allows for the production of IpSs, which are used to study degenerative diseases like Parkinson’s without having to deal with ethical objections.