Just physically squeezing cells or bathing them in acidic conditions can readily reprogram them into an embryonic state
In 2006, Japanese researchers reported a technique for creating cells that have the embryonic ability to turn into almost any cell type in the mammalian body — the now-famous induced pluripotent stem (iPS) cells. In papers published this week in Nature, another Japanese team says that it has come up with a surprisingly simple method — exposure to stress, including a low pH — that can make cells that are even more malleable than iPS cells, and do it faster and more efficiently.
“It’s amazing. I would have never thought external stress could have this effect,” says Yoshiki Sasai, a stem-cell researcher at the RIKEN Center for Developmental Biology in Kobe, Japan, and a co-author of the latest studies. It took Haruko Obokata, a young stem-cell biologist at the same centre, five years to develop the method and persuade Sasai and others that it works. “Everyone said it was an artefact — there were some really hard days,” says Obokata.
Obokata says that the idea that stressing cells might make them pluripotent came to her when she was culturing cells and noticed that some, after being squeezed through a capillary tube, would shrink to a size similar to that of stem cells. She decided to try applying different kinds of stress, including heat, starvation and a high-calcium environment. Three stressors — a bacterial toxin that perforates the cell membrane, exposure to low pH and physical squeezing — were each able to coax the cells to show markers of pluripotency.
But to earn the name pluripotent, the cells had to show that they could turn into all cell types — demonstrated by injecting fluorescently tagged cells into a mouse embryo. If the introduced cells are pluripotent, the glowing cells show up in every tissue of the resultant mouse. This test proved tricky and required a change in strategy. Hundreds of mice made with help from mouse-cloning pioneer Teruhiko Wakayama at the University of Yamanashi, Japan, were only faintly fluorescent. Wakayama, who had initially thought that the project would probably be a “huge effort in vain”, suggested stressing fully differentiated cells from newborn mice instead of those from adult mice. This worked to produce a fully green mouse embryo.
Still, the whole idea was radical, and Obokata’s hope that glowing mice would be enough to win acceptance was optimistic. Her manuscript was rejected multiple times, she says.
To convince sceptics, Obokata had to prove that the pluripotent cells were converted mature cells and not pre-existing pluripotent cells. So she made pluripotent cells by stressing T cells, a type of white blood cell whose maturity is clear from a rearrangement that its genes undergo during development. She also caught the conversion of T cells to pluripotent cells on video. Obokata called the phenomenon stimulus-triggered acquisition of pluripotency (STAP).
The results could fuel a long-running debate. For years, various groups of scientists have reported finding pluripotent cells in the mammalian body, such as the multipotent adult progenitor cells described by Catherine Verfaillie, a molecular biologist then at the University of Minnesota in Minneapolis. But others have had difficulty reproducing such findings. Obokata started the current project in the laboratory of tissue engineer Charles Vacanti at Harvard University in Cambridge, Massachusetts, by looking at cells that Vacanti’s group thought to be pluripotent cells isolated from the body. But her results suggested a different explanation: that pluripotent cells are created when the body’s cells endure physical stress. “The generation of these cells is essentially Mother Nature’s way of responding to injury,” says Vacanti, a co-author of the latest papers.
One of the most surprising findings is that the STAP cells can also form placental tissue, something that neither iPS cells nor embryonic stem cells can do. That could make cloning dramatically easier, says Wakayama.
The Latest on: New Way to Make Stem Cells
[google_news title=”” keyword=”New Way to Make Stem Cells” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: New Way to Make Stem Cells
- 12-year-old spreads awareness on stem donation after receiving gift of lifeon May 9, 2024 at 10:32 am
THIS WAS MADE POSSIBLE THROUGH STEM DONATIONS ... COMING YOUR WAY. ACCORDING TO NMDP, A NONPROFIT SUPPORTING CELL THERAPY, 70% OF PATIENTS DO NOT HAVE A TRANSPLANT MATCH IN THEIR FAMILIES. IMAGINE ...
- 17-Year-Old Indian STEM Cell Recipient Finds His "Miracle Match"on May 8, 2024 at 7:20 am
The likelihood of a man from Russia to be a genetic match for a boy from India for bone marrow transplant is almost none, said Dr Sunil Bhat of Narayana Group of Hospitals.And yet, 17-year-old ...
- A 12-Year-Old Is First to Start New Sickle Cell Treatmenton May 6, 2024 at 1:25 pm
He's the first patient outside of a clinical trial to start a new genetic treatment that was shown in clinical trials to cure 88% of people of the hallmark symptoms of sickle cell disease.
- First Patient Begins Newly Approved Sickle Cell Gene Therapyon May 6, 2024 at 4:01 am
A 12-year-old boy in the Washington, D.C., area faces months of procedures to remedy his disease. “I want to be cured,” he said.
- Grandfather saved by stem cells flies in to meet donoron May 5, 2024 at 4:02 pm
A grandfather from Canada has flown thousands of miles to the UK to meet the stem cell donor who helped save his life.
- Researchers Breed Mice With Hybrid Brains Containing Cells From Ratson May 2, 2024 at 2:00 pm
In one experiment, rat neurons helped mice restore their senses of smell—the first time any animal has perceived the world through the sensory hardware of another species ...
- Researchers Develop New Tool for Enhanced Understanding of Stem Cell Aging in the Brainon May 2, 2024 at 12:50 am
Researchers can use the light naturally thrown off by biological specimens to better study the different states of stem cells in the nervous system, thanks to a tool developed at the University of ...
- Study introduces improved way to grow cells that give rise to kidney's filtration systemon April 30, 2024 at 8:00 am
In a study published in Cell Stem Cell, USC scientists report significant progress in cultivating nephron progenitor cells (NPCs), the cells destined to form the kidney's filtration system, the ...
- New and improved way to grow the cells that give rise to the kidney's filtration systemon April 29, 2024 at 5:00 pm
Scientists report significant progress in cultivating nephron progenitor cells (NPCs), the cells destined to form the kidney's filtration system, the nephrons. NPCs hold immense promise for ...
- Using stem cell-derived heart muscle cells to advance heart regenerative therapyon April 26, 2024 at 6:01 am
Study shows that cardiac spheroids, derived from human induced pluripotent stem cells ... be needed when transporting the cells to clinics, which would make the proposed approach less expensive ...
via Bing News