Scientists hail breakthrough in stem cells

[Buster's Uncle]

Scientists hail breakthrough in embryonic-like stem cells
Reuters
By Kate Kelland, Health and Science Correspondent  47 minutes ago



LONDON (Reuters) - In experiments that could open a new era in stem cell biology, scientists have found a simple way to reprogramme mature animal cells back into an embryonic-like state that allows them to generate many types of tissue.

The research, described as game-changing by experts in the field, suggests human cells could in future be reprogrammed by the same technique, offering a simpler way to replace damaged cells or grow new organs for sick and injured people.

Chris Mason, chair of regenerative medicine bioprocessing at University College London, who was not involved in the work, said its approach in mice was "the most simple, lowest-cost and quickest method" to generate so-called pluripotent cells - able to develop into many different cell types - from mature cells.

"If it works in man, this could be the game changer that ultimately makes a wide range of cell therapies available using the patient's own cells as starting material - the age of personalized medicine would have finally arrived," he said.

The experiments, reported in two papers in the journal Nature on Wednesday, involved scientists from the RIKEN Center for Developmental Biology in Japan and Brigham and Women's Hospital and Harvard Medical School in the United States.

The researchers took skin and blood cells, let them multiply, then subjected them to stress "almost to the point of death", they explained, by exposing them to various events including trauma, low oxygen levels and acidic environments.

One of these "stressful" situations was simply to bathe the cells in a weak acid solution for around 30 minutes.

Within days, the scientists found that the cells had not only survived but had also recovered by naturally reverting into a state similar to that of an embryonic stem cell.

These stem cells - dubbed Stimulus-Triggered Acquisition of Pluripotency, or STAP, cells by the researchers - were then able to differentiate and mature into different types of cells and tissue, depending on the environments they were put in.


"NEW ERA"

"If we can work out the mechanisms by which differentiation states are maintained and lost, it could open up a wide range of possibilities for new research and applications using living cells," said Haruko Obokata, who lead the work at RIKEN.

Stem cells are the body's master cells and are able to differentiate into all other types of cells. Scientists say that by helping to regenerate tissue and potentially grow new organs, they could offer ways of tackling diseases for which there are currently only limited treatments.

Recent experimental research has seen stem cells used to create a functional human liver and to create beating heart muscle tissue.

There are two main types of stem cells: embryonic ones, harvested from embryos, and adult or iPS cells, which are taken from skin or blood and reprogrammed back into stem cells.

Because the harvesting of embryonic stem cells requires the destruction of a human embryo, the technique has been the subject of ethical concerns and protests from pro-life campaigners.

Dusko Ilic, a reader in stem cell science at Kings College London, said the Nature studies described "a major scientific discovery" and predicted their findings would open "a new era in stem cell biology".

"Whether human cells would respond in a similar way to comparable environmental cues ... remains to be shown," he said in an emailed comment. "I am sure that the group is working on this and I would not be surprised if they succeed even within this calendar year."

Robin Lovell-Badge, a stem cell expert at Britain's National Institute for Medical Research, said it would be some time before the exact nature and capabilities of the STAP cells would be fully understood by scientists - and only then would their full potential in medicine become clearer.

"But the really intriguing thing to discover will be the mechanism underlying how a low pH shock triggers reprogramming," he said. "And why does it not happen when we eat lemon or vinegar, or drink cola?"


http://news.yahoo.com/scientists-create-embryonic-type-stem-cells-without-embryos-120428415.html

[Buster's Uncle]

A New Method for Making Stem Cells
LiveScience.com
By Tanya Lewis, Staff Writer  4 hours ago



Using a new method for making stem cells, researchers created an entire mouse fetus.



Scientists have found a new way of creating stem cells, which are cells that have the ability to turn into any type of tissue, using mouse cells. If the method works for human cells, it could ultimately be used to create tissue for people who need organ transplants, and to study diseases such as cancer.

The new method involves exposing cells taken from a mouse spleen to an acidic environment. After doing this, the scientists found they had created cells that were "pluripotent" — capable of turning into most types of cells in the body, including those found in the lungs, muscle, bone, blood, skin or nervous system. The researchers called the stem cells they made "STAP cells" (an abbreviation for stimulus-triggered acquisition of pluripotency).

If the findings are replicated, "this result has the potential to be very significant," said Linzhao Cheng, a professor of medicine and oncology at the Johns Hopkins University School of Medicine, who was not involved in the research. [Video: STAP cells develop into an embryo]

Researchers in Japan first demonstrated the ability to make stem cells from adult cells in 2006. This method uses viruses to insert new genes into adult cells, and produces cells called induced pluripotent stem cells (iPSCs).

But the new method of using acid doesn't require manipulating the cells' DNA, and may even be faster, researchers said.

The study not only shows that STAP cells offer an alternative way to generate stem cells for regenerative medicine, but also that they could help scientists learn about how tumors develop in cancer, Cheng told LiveScience.


Reprogramming cells

Normally, once cells in the body have become specialized — for example, by becoming spleen cells – they can no longer change course and develop into other types of cells. One goal of stem cell research is to find ways to reset adult cells, so that they can change course and grow into whatever tissue a person might need. That could mean a replacement of heart tissue damaged by a heart attack, or a new lung kidney to replace one ravaged by cancer.

Common wisdom holds that in order to make cells revert to their unspecialized state, researchers must either transfer the cell nucleus, or add a complex cocktail of substances that control how DNA gets made into proteins.

"I asked, can it be done without manipulating the nucleus?" said Haruko Obokata of the RIKEN Center for Developmental Biology in Japan, leader of the research described online today (Jan. 29) in two papers in the journal Nature.

Studies of plants have shown that a stressful environment can reprogram cells into an immature state. And, from this state, the cells can develop into an entirely new plant. But no one had reprogrammed animal cells in that way. [Inside Life Science: Once Upon a Stem Cell]

Obokata and her colleagues developed a new method to reprogram adult mouse cells. They took spleen cells from 1-week-old mice and bathed the cells in acidic fluid, at human body temperature, for 25 minutes.

They found that after the acid treatment, the cells indeed reverted to a pluripotent state like that seen in embryonic stem cells.

The scientists tested the cells' potential by injecting them into mouse embryos that were already growing, but still at a very early stage of development. The researchers found these embryos developed into healthy mice that were "chimaeras," meaning they contained genetic material from both the STAP cells and the original cells of the embryo.

In a second study, the researchers found the STAP cells could develop into not only into the cells of the mouse embryo, but also into the cells of its placenta — a strong demonstration of the cells' potential to develop into different cell types.

In addition, the scientists showed that STAP cells could be converted into self-renewing stem cells similar to embryonic stem cells.


Way of the future?

Compared with the time it takes to perform the current method, of creating iPSCs, the new method is much quicker, Obokata said.

In addition to the acidic treatment, the researchers tested whether other stresses — such as squeezing the cells, heating them or depriving them of nutrients — could also coax mature cells into becoming pluripotent. Initial findings suggest that some of these other stresses could have the same effect as the acidic treatment, the researchers said.

Paul Frenette, a stem cell biologist at Albert Einstein College of Medicine in New York who had no role in the study, called the new method "very exciting."

Many scientists have been spending a lot of effort on finding ways to reprogram cells, so achieving this by simply changing the acidity of the environment is remarkable, Frenette told LiveScience.

Other labs will try to replicate the findings in mice, and ultimately in human cells. The new method is"very easy to do, so we will see how quickly it's reproduced," Frenette said.


http://news.yahoo.com/method-making-stem-cells-164813262.html

[Buster's Uncle]

New simple way to reset cells could be transplant "game changer"
AFP
By Richard Ingham  4 hours ago



A scientific researcher extracts the RNA from embryonic stem cells in a laboratory, at the Univestiry of Sao Paulo's human genome research center, in Sao Paulo, Brazil, on March 4, 2008 (AFP Photo/Mauricio Lima)



Paris (AFP) - Scientists Wednesday reported a simple way to turn animal cells back to a youthful, neutral state, a feat hailed as a "game-changer" in the quest to grow transplant tissue in the lab.

The research, reported in the journal Nature, could be the third great advance in stem cells -- a futuristic field that aims to reverse Alzheimer's, cancer and other crippling or lethal diseases.

The latest breakthrough comes from Japan, as did its predecessor which earned its inventor a Nobel Prize.

The new approach -- provided it overcomes safety hurdles -- could smash cost and technical barriers in stem-cell research, said independent commentators.

"If it works in man, this could be the game-changer that ultimately makes a wide range of cell therapies available using the patient's own cells as starting material," said Chris Mason, a professor of regenerative medicine at University College London.



This handout picture, released from Kyoto University on October 5, 2012 shows a mouse (R) which was born from an egg cell, made from indiced pluripotent stem (iPS) cells of a mouse, and this mouse's offspring (AFP Photo/Kyoto University)


"The age of personalised medicine will have arrived."

Stem cells are primitive cells that, as they grow, differentiate into the various specialised cells that make up the different organs -- the brain, the heart, kidney and so on.

The goal is to create stem cells in the lab and nudge them to grow into these differentiated cells, thus replenishing organs damaged by disease or accident.

One of the obstacles, though, is ensuring that these transplanted cells are not attacked as alien by the body's immune system.

To achieve that, the stem cells would have to carry the patient's own genetic code, to identify them as friendly.



A scientific researcher manipulates drops of embryonic stem cells in a laboratory, at 'Hospital do Coracao' heart institute, in Sao Paulo, Brazil, on 5 March, 2008 (AFP Photo/Mauricio Lima)


In 1998 came the first gain: the use of cloning technology -- pioneered with Dolly the sheep -- to harvest stem cells from early-stage embryos grown from the donor's own DNA.

Hugely versatile, these "pluripotent" stem cells are controversial as the method entails destroying the embryo, something opposed by religious conservatives and others.

In 2006, a team led by Shinya Yamanaka of Kyoto University, who was a co-recipient of the 2012 Nobel Prize for Medicine, created so-called induced pluripotent stem cells (iPS).

With this, the team took mature cells and coded them with four genes, "rewinding" the cells' genetic programmes to return them to a juvenile state.

The technique had to overcome an early hurdle of causing tumours in cells and still faces problems with efficiency -- less than one percent of adult cells typically are reprogrammed successfully.



Scientists work on stem cell cultures at the Transplantation Biology Research Centre situated at The Institute of Kidney Disease and Research Centre (IKDRC), Civil Hospital campus in Ahmedabad on February 6, 2013 (AFP Photo/Sam Panthaky)


The latest breakthrough, pioneered by Haruko Obokata at the RIKEN Center for Developmental Biology in Kobe, takes an entirely different and surprisingly low-tech approach.


'Hallmarks of pluripotency'

White blood cells in newborn mice were returned to a versatile state by incubating them in a solution with high acidity for 25 minutes, followed by a five minute spin in a centrifuge and a seven-day spell of immersion in a growth culture.

Called stimulus-triggered acquisition of pluripotency (STAP) cells, the innovation breaks new ground.

Until now, only plant cells, and not mammal cells, have been found to reprogramme back to a youthful state through simple environmental factors.



Stem cells are viewed on a computer screen at the University of Connecticut`s (UConn) Stem Cell Institute at the UConn Health Center on August 27, 2010 in Farmington, Connecticut (AFP Photo/Spencer Platt)


"These STAP cells show all the hallmarks of pluripotency," Obokata said Tuesday in an Internet briefing with journalists.

STAP cells appear to have a limited ability to self-renew, and it has yet to be seen if they can be acquired from humans.

Only much later may trials in humans follow.

It took 13 years before the first trials with embryonic stem cells, and six years before the first iPS trials.

Dusko Ilic, a stem-cell scientist at Kings College London, said the approach "is indeed revolutionary."

But he cautioned: "It does not bring stem cell-based therapy closer."

"We will need to use the same precautions for the cells generated in this way as for the cells isolated from embryos or reprogrammed with a standard method," he said in comments reported by London's Science Media Centre.


http://news.yahoo.com/simple-way-reset-cells-could-transplant-quot-game-161353018.html

[Buster's Uncle]

Study Says New Method Could Be a Quicker Source of Stem Cells
By ANDREW POLLACKJAN. 29, 2014


A surprising study has found that a simple acid bath might turn cells in the body into stem cells that could one day be used for tissue repair and other medical treatments.

The technique, performed only with cells from mice, might turn out to be a quicker and easier source of multipurpose stem cells than methods now in use.

“If reproducible in humans, this could be a paradigm changer,” said Dr. Robert Lanza, a stem-cell scientist who was not involved in the work. Dr. Lanza, who is chief scientific officer of the biotechnology company Advanced Cell Technology, said the technique might also make it easier to clone animals or even people, raising ethical questions.

The new technique was developed by researchers at the Riken Center for Development Biology in Kobe, Japan, and at Brigham and Women’s Hospital and Harvard Medical School in Boston. Two papers by the researchers were published in the journal Nature on Wednesday.

Some experts expressed caution, saying more needed to be known about the new approach and that existing techniques for making stem cells had improved markedly in recent years.

“The existing methods are already quite advanced,” said Sheng Ding, a scientist at the University of California, San Francisco, and the affiliated Gladstone Institutes. “It’s too early to say this is better, safer or more practical.”

Certain stem cells can be easily grown in the laboratory and can turn into any type of cell in the body, which is called pluripotency. Researchers think these stem cells may one day be used to repair damaged cells and organs in the body, though experiments trying this in people are in very early stages.

At first, interest focused on so-called embryonic stem cells, which could be obtained at first only by destroying human embryos, which is ethically contentious.

Several years ago, Shinya Yamanaka of Kyoto University in Japan and other scientists developed a way to turn cells from the body, such as skin or blood cells, into stem cells, avoiding the need to destroy embryos. That work won Dr. Yamanaka a Nobel Prize.

These cells, called induced pluripotent stem cells, have an additional advantage over embryonic cells in that they can be created from a particular patient. Therefore, any cells derived from those stem cells and transplanted back into the patient would not be rejected by the patient’s immune system.

But creating those induced cells requires genetic changes to the cells, raising some questions about whether they can be used for medical therapy.

The new technique does away with deliberate genetic changes. Instead, it involves subjecting specialized cells, like blood or skin cells, to stress.

The researchers in Kobe and Boston tried various stresses, including squeezing the cells, but found that bathing the cells for half an hour in a mildly acidic solution seemed to work best. The technique worked for cells taken from various organs of newborn mice, but the efficiency was highest using white blood cells.

The mice from which the cells were taken had been genetically engineered so their cells would glow green if Oct4, a gene associated with pluripotent cells, was active.

After the acid bath, the cells were grown in culture. Many died from the exposure to acid, but among those that survived, many were glowing green by the seventh day. The researchers called these STAP cells, standing for stimulus-triggered acquisition of pluripotency.

To prove the STAP cells could indeed turn into every cell type in the body, researchers injected the cells into early mice embryos. These embryos grew into mice, called chimeras, with cells derived from the STAP cells in all tissues of their bodies. The mice could reproduce and pass along the genetic characteristics from those cells.

The fact that descendants of the STAP cells could function in mice and their offspring also provided evidence that the cells were not abnormal.

“I was really surprised the first time we saw the chimeric mice,” said Haruko Obokata, a biologist at Riken and the lead author of the two papers in Nature. She had worked on the project for several years, at first as a researcher at Brigham and Women’s under Dr. Charles A. Vacanti.

If the technique is to be used to treat patients, it would have to work with cells taken from adult humans, not newborn mice. Dr. Obokata said the technique worked using cells from older mice, but not as efficiently. She said researchers were testing if the technique worked with human cells.

One problem with the STAP cells was that they did not last long in the laboratory and could not reproduce well. But the researchers found they could grow the cells in a different culture medium and get them to change into cells that could replenish themselves easily. They called these STAP stem cells.

One surprising finding, the researchers said, was that the STAP cells could form material for the placenta, not just the embryo. That could theoretically allow STAP cells to be used to clone animals, said Dr. Lanza. The current technique to clone involves a complicated process that has not worked for humans.

Scientists said it would be interesting to understand just how and why stress leads already specialized cells to revert to a more primordial state.

There is some speculation this could be a response that has evolved to help organisms survive stress. But a reversion to stemlike cells is not known to happen in people’s bodies when they are exposed to stress.

Dr. Ding said that since stem cells could form tumors, the findings might help explain why stress appeared to increase the risk of cancer.


http://www.nytimes.com/2014/01/30/business/study-says-new-method-could-be-a-quicker-source-of-stem-cells.html?partner=yahoofinance