Stem cells with the capacity to form any type of tissue can be created from adult cells without destroying embryos, according to new research that suggests a way of sidestepping ethical controversy over the field. Three separate teams of scientists have used genetic trickery to wind back the biological clock of mature skin cells from mice, to give them the unlimited potential of stem cells that are normally found only in embryos. Though it remains uncertain whether the same technique would work in humans, the successes rai... lire la suite
Acclaimed stem cell researcher Shinya Yamanaka, MD, PhD, has reported that he and his Kyoto University colleagues have successfully reprogrammed human adult cells to function like pluripotent embryonic stem (ES) cells. Because it circumvents much of the controversy and restrictions regarding generation of ES cells from human embryos, this breakthrough, reported in the journal Cell, should accelerate the pace of stem cell research.
Stem cells with the capacity to form any type of tissue can be created from adult cells without destroying embryos, according to new research that suggests a way of sidestepping ethical controversy over the field. Three separate teams of scientists have used genetic trickery to wind back the biological clock of mature skin cells from mice, to give them the unlimited potential of stem cells that are normally found only in embryos.
Scientists have discovered a new source of stems cells and have used them to create muscle, bone, fat, blood vessel, nerve and liver cells in the laboratory. The first report showing the isolation of broad potential stem cells from the amniotic fluid that surrounds developing embryos was published in Nature Biotechnology.
A 65-year-old Finnish man received a new upper jaw that was grown in his abdomen using his own stem cells. Scientists had isolated stem cells from the patient’s fat, and sorted out the type of cells that could grow into bone tissue. The cells were applied to a custom jaw-shaped scaffold and implanted in his [.
A group of researchers in Switzerland has published a study appearing in the Oct 1 advance online edition of the Journal Nature that shows how the cornea uses stem cells to repair itself. Using mouse models they demonstrate that everyday wear and tear on the cornea is repaired from stem cells residing in the corneal epithelium, and that more serious repair jobs require the involvement of other stem cells that migrate from the limbus, a region between the cornea and the conjunctiva, the white part of the eye.
Researchers at the Joslin Diabetes Center have demonstrated for the first time that transplanted muscle stem cells can both improve muscle function in animals with a form of muscular dystrophy and replenish the stem cell population for use in the repair of future muscle injuries. I’m very excited about this,” said lead author Amy J.
UC Irvine scientists have found a new way to sort stem cells that should be quicker, easier and more cost-effective than current methods. The technique could in the future expedite therapies for people with conditions ranging from brain and spinal cord damage to Alzheimer's and Parkinson's diseases.
In some ways, certain tumors resemble bee colonies, says pathologist Tan Ince. Each cancer cell in the tumor plays a specific role, and just a fraction of the cells serve as “queens,” possessing the unique ability to maintain themselves in an unspecialized state and seed new tumors. These cells can also divide and produce the “worker” cells that form the bulk of the tumor.
Scientists have developed a new procedure for the differentiation of human embryonic stem cells, with which they have created the first transplantable source of lung epithelial cells. The method involves the use of protein markers under the control of cell-specific promoters to convert undifferentiated human embryonic stem cells into highly-specialized cells.
Stem cells grew, multiplied and differentiated into brain cells on a new three-dimensional scaffold of tiny protein fragments designed to be more like a living body than any other cell culture system. An MIT engineer and Italian colleagues will report the invention-which may one day replace the ubiquitous Petri dish for growing cells-in the Dec.
Scientists at Duke University Medical Center have demonstrated they can grow human stem cells in the laboratory by blocking an enzyme that naturally triggers stem cells to mature and differentiate into specialized cells. The discovery may enable scientists to rapidly grow stem cells and transplant them into patients with blood disorders, immune defects and select genetic diseases, said the Duke researchers.
Some of the most challenging obstacles limiting the reprogramming of mature human cells into stem cells may not seem quite as daunting in the near future. Two independent research papers, published by Cell Press in the September 11th issue of the journal Cell Stem Cell, describe new tools that provide invaluable platforms for elucidating the molecular, genetic, and biochemical mechanisms associated with reprogramming.
Researchers at Children’s Hospital Boston report a new and efficient strategy, using eggs alone, for creating mouse embryonic stem cells that can be transplanted without the risk of rejection because the cells are compatible with the recipient’s immune system. The findings are published online in the journal Science on December 14.
Scientists have demonstrated for the first time that embryonic stem (ES) cells cultured in the laboratory can produce sperm with the capacity to produce viable offspring. The research, published in the July issue of Developmental Cell, opens many exciting avenues for future studies, including investigation of mechanisms involved in sperm production and development of new treatment strategies for infertility.
From Massachusetts: Thu Sep 25, 2008 2: pm EDT Researchers have developed a safer way to make powerful stem cells from ordinary skin cells, taking one more step toward so-called regenerative medicine. They used a common cold virus to carry transformative genes into ordinary mouse cells, making them look and act like embryonic stem cells.
For cells that hold so much promise, stem cells’ potential has so far gone largely untapped. But new research from Rockefeller University and Howard Hughes Medical Institute scientists now shows that adult stem cells taken from skin can be used to clone mice using a procedure called nuclear transfer.
For many years, researchers believed that stem cells in the bone marrow spent most of their existence in a slumber-like state, unaware of — and unaffected by — the daily battles fought by the body's immune system. Not so. Scientists at the Oklahoma Medical Research Foundation have discovered that marrow stem cells — undifferentiated cells that eventually give rise to the blood cells that fight infection — possess receptors that recognize bacteria and viruses.
In the rancorous public debate over federal research funding, stem cells are generally assigned to one of two categories: embryonic or adult. But that’s a false dichotomy and an oversimplification. A new University of Michigan study adds to mounting evidence that stem cells in the developing fetus are distinct from both embryonic and adult stem cells.
A report in the January issue of Cell Metabolism, a publication of Cell Press, provides new evidence explaining how stem cells known as satellite cells contribute to building muscles up in response to exercise. These findings could lead to treatments for reversing or improving the muscle loss that occurs in diseases such as cancer and AIDS as well as in the normal aging process, according to the researchers.
Researchers at the University of Pennsylvania School of Veterinary Medicine have derived uniparental embryonic stem cells - created from a single donor’s eggs or two sperm - and, for the first time, successfully used them to repopulate a damaged organ with healthy cells in adult mice. Their findings demonstrate that single-parent stem cells can proliferate normally in an adult organ and could provide a less controversial alternative to the therapeutic cloning of embryonic stem cells.