Embryonic stem cells, prized for their astonishing ability to apparently transform into any kind of cell in the body, acquire their identities in part by interacting with their surroundings - even when they are outside of the body in a laboratory dish, University of Florida scientists report. Using an animal model of embryonic stem cell development, researchers with UF’s McKnight Brain Institute have begun to answer one of the most fundamental questions in science - how does a batch of immature cells give rise to an organ... lire la suite
Researchers have discovered the small number of cells in pancreatic cancer that are capable of fueling the tumor's growth. The finding is the first identification of cancer stem cells in pancreatic tumors. Cancer stem cells are the small number of cancer cells that replicate to drive tumor growth.
Embryonic stem cells, prized for their astonishing ability to apparently transform into any kind of cell in the body, acquire their identities in part by interacting with their surroundings - even when they are outside of the body in a laboratory dish, University of Florida scientists report. Using an animal model of embryonic stem cell development, researchers with UF’s McKnight Brain Institute have begun to answer one of the most fundamental questions in science - how does a batch of immature cells give rise to an organ as extraordinarily complex as the human brain?
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.
A startling discovery on the development of human embryonic stem cells by scientists at McMaster University will change how future research in the area is done. An article published in the prestigious scientific journal Nature this week reports on a new understanding of the growth of human stem cells.
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.
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.
Researchers at UCLA today announced they have transformed adult stem cells taken from human adipose – or fat tissue – into smooth muscle cells, which help the normal function of a multitude of organs like the intestine, bladder and arteries. The study may help lead to the use of fat stem cells for smooth muscle tissue engineering and repair.
Researchers from the UCLA AIDS Institute and the Institute for Stem Cell Biology and Medicine have demonstrated for the first time that human embryonic stem cells can be genetically manipulated and coaxed to develop into mature T-cells, raising hopes for a gene therapy to combat AIDS. The study, to be published the week of July 3 in the online edition of the Proceedings of the National Academy of Sciences, found that it is possible to convert human embryonic stem cells into blood-forming stem cells that in turn can differentiate into the helper T-cells that HIV specifically targets.
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 the first time, researchers have enticed transplants of embryonic stem cell-derived motor neurons in the spinal cord to connect with muscles and partially restore function in paralyzed animals. The study suggests that similar techniques may be useful for treating such disorders as spinal cord injury, transverse myelitis, amyotrophic lateral sclerosis (ALS), and spinal muscular atrophy.
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.
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.
A human embryonic stem cell is reined in – prevented from giving up its unique characteristics of self-renewal and pluripotency – by the presence of a protein modification that stifles any genes that would prematurely instruct the cell to develop into heart or other specialized tissue. But, thanks to the simultaneous presence of different protein modifications, stem cells are primed and poised, ready to develop into specialized body tissue, Singapore scientists reported in last month's issue of the journal Cell Stem Cell.
With ethical issues concerning use of discarded embryos and technical problems hindering development of stem cell therapies, scientists in Korea are reporting the first successful use of a drug-like molecule to transform human muscle cells into nerve cells. Their report, scheduled for the August 8 issue of the Journal of the American Chemical Society, a weekly journal, states that the advance could lead to new treatments for stroke, Alzheimer's disease, Parkinson's disease and other neurological disorders.
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.
Researchers have shown that bone marrow stem cells injected into a damaged inner ear can speed hearing recovery after partial hearing loss. The related report by Kamiya et al, “Mesenchymal stem cell transplantation accelerates hearing recovery through the repair of injured cochlear fibrocytes,” appears in the July issue of The American Journal of Pathology.
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 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.
Researchers from Biotech Research & Innovation Centre (BRIC) at University of Copenhagen have identified a new group of proteins that regulate the function of stem cells. The results are published in the new issue of Cell. All living organisms, including human beings, consist of a number of specialised cell types that all originate from the same type of primal cell;
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.