 |
|
Master switches found for adult blood stem cells
February 12, 2007Johns Hopkins Kimmel Cancer Center scientists have found a set of "master switches" that keep adult blood-forming stem cells in their primitive state. Unlocking the switches' code may one day enable scientists to grow new blood cells for transplant into patients with cancer and other bone marrow disorders.
The scientists located the control switches not at the gene level, but farther down the protein production line in more recently discovered forms of ribonucleic acid, or RNA. MicroRNA molecules, once thought to be cellular junk, are now known to switch off activity of the larger RNA strands which allow assembly of the proteins that let cells grow and function.
To halt protein assembly, microRNAs pair up with matching full-length RNA, then fold and twist it, rendering the larger RNA useless. But the RNA pairings are not perfect, and one microRNA can latch on to several hundred RNA strands. "They act like a single circuit breaker to efficiently control hundreds of RNAs," says Civin, the Herman and Walter Samuelson Professor of Cancer Research.
"We're looking for ways to flip these microRNA switches, to control when stem cells grow into new blood cells," says Robert Georgantas, Ph.D., research associate at the Johns Hopkins Kimmel Cancer Center and first and corresponding author of the study.
To identify the key microRNAs, Georgantas sifted through thousands of RNA pieces with a custom-built, computer software program. Its algorithms let the software, fed data from samples of blood and bone marrow from healthy donors, match RNA pairs. The outcome was a core set of 33 microRNAs that match with more than 1,200 of the larger variety RNA already known to be important for stem-cell maturation.
Georgantas and Civin currently are testing whether these pair predictions are valid by using a non-reproducing virus to insert genetic instructions for each of the 33 microRNAs into adult stem cells. They'll then be cultured in Petri dishes. MicroRNA-155 — the first microRNA tested — was predicted to stop stem cells from developing into red and white blood cells. As expected, stem cells without microRNA-155 matured: they formed approximately 75 red and 150 white blood cell colonies per dish. Stem cells with microRNA-155 matured into far fewer red and white cell colonies — about seven and 30 per dish, respectively.
"Using microRNAs to stall an adult blood stem cell in its early stage could help us grow new ones in test tubes, and perhaps give us more insight into stem-cell maturation for other tissue types," says Civin.
Johns Hopkins Medical Institutions
Stem Cells Current Events and Stem Cells News RSSChemists influence stem-cell development with geometry
University of Chicago scientists have successfully used geometrically patterned surfaces to influence the development of stem cells. The new approach is a departure from that of many stem-cell biologists, who focus instead on uncovering the role of proteins in controlling the fate of stem cells.
Amniotic fluid cells more efficiently reprogrammed to pluripotency than adult cells
In a breakthrough that may help fill a critical need in stem cell research and patient care, researchers at Mount Sinai School of Medicine have demonstrated that skin cells found in human amniotic fluid can be efficiently "reprogrammed" to pluripotency, where they have characteristics similar to human embryonic stem cells that can develop into almost any type of cell in the human body.
UC Irvine biologists help sequence Hydra genome
UC Irvine researchers have played a leading role in the genome sequencing of Hydra, a freshwater polyp that has been a staple of biological research for 300 years.
Researchers characterize stem cell function
The promise of stem cells lies in their unique ability to differentiate into a multitude of different types of cells. But in order to determine how to use stem cells for new therapeutics, scientists and engineers need to answer a fundamental question: if a stem cell changes to look like a certain type of cell, how do we know if it will behave like a certain type of cell?
Novel stroke treatment passes safety stage of UCI-led clinical trial
A clinical research trial of a new treatment to restore brain cells damaged by stroke has passed an important safety stage, according to the UC Irvine neurologist who led the effort.
Model may offer better understanding of embryonic development
A mathematical model developed at Purdue University can predict complex signaling patterns that could help scientists determine how stem cells in an embryo later become specific tissues, knowledge that could be used to understand and treat developmental disorders and some diseases.
University of Michigan scientists discover bone marrow can harbor HIV-infected cells
University of Michigan scientists have identified a new reservoir for hidden HIV-infected cells that can serve as a factory for new infections.
Repeated anesthesia can affect childrens ability to learn
There is a link between repeated anaesthesia in children and memory impairment, though physical activity can help to form new cells that improve memory, reveals new research from the Sahlgrenska Academy at the University of Gothenburg, Sweden.
A new indicator of poor prognosis in node-negative colorectal cancer patients
Tumor budding at the invasive tumor front of colorectal cancer is recognized as an independent prognostic factor significantly related to both lymph node and distant metastasis.
Breakthrough reveals blood vessel cells are key to growing unlimited amounts of adult stem cells
In a leap toward making stem cell therapy widely available, researchers at the Ansary Stem Cell Institute at Weill Cornell Medical College have discovered that endothelial cells, the most basic building blocks of the vascular system, produce growth factors that can grow copious amounts of adult stem cells and their progeny over the course of weeks.
More Stem Cells Current Events and Stem Cells News Articles
 |
Essentials of Stem Cell Biology, Second Edition by Robert Lanza (Editor), John Gearhart (Editor), Brigid Hogan (Editor), Douglas Melton (Editor), Roger Pederson (Editor), E. Donnall Thomas (Editor), James Thomson (Editor), Sir Ian Wilmut (Editor) First developed as an accessible abridgement of the successful Handbook of Stem Cells, Essentials of Stem Cell Biology serves the needs of the evolving population of scientists, researchers, practitioners and students that are embracing the latest advances in stem cells. Representing the combined effort of seven editors and more than 200 scholars and scientists whose pioneering work has defined our understanding of stem cells, this book combines the prerequisites for a general understanding of adult and embryonic stem cells with a presentation by the world's experts of the latest research information about specific organ systems. From basic biology/mechanisms, early development, ectoderm, mesoderm, endoderm, methods to application of stem cells to specific human diseases, regulation and... |
 |
Stem Cells For Dummies by Lawrence S.B. Goldstein (Author), Meg Schneider (Author) The first authoritative yet accessible guide to this controversial topic Stem Cell Research For Dummies offers a balanced, plain-English look at this politically charged topic, cutting away the hype and presenting the facts clearly for you, free from debate. It explains what stem cells are and what they do, the legalities of harvesting them and using them in research, the latest research findings from the U.S. and abroad, and the prospects for medical stem cell therapies in the short and long term. Explains the differences between adult stem cells and embryonic/umbilical cord stem cells Provides both sides of the political debate and the pros and cons of each side's opinions Includes medical success stories using stem cell therapy and its promise for the... |
 |
Stem Cell Now by Christopher Thomas Scott (Author) The essential account of the most important scientific advance—and most volatile ethical debate—of our time While many believe stem cell research holds the key to curing a wide range of ailments, others see this research as opening a Pandora’s box that will devalue human life. In Stem Cell Now, Christopher Scott—executive director of Stanford University’s Stem Cells and Society Program—lays out the scientific and ethical issues surrounding this national dilemma. Scott guides readers through the latest advances in stem cell research in clear, accessible language, telling the stories of the researchers who are exploring the potential of stem cells to cure cancer, grow new organs, and repair the immune system. He also leads readers through a... |
 |
The Stem Cell Divide: The Facts, the Fiction, and the Fear Driving the Greatest Scientific, Political, and Religious Debate of Our Time by Michael Bellomo (Author) There has been much recent debate about the merits, dangers, and nature of stem cell research. Some see in it the answer to every debilitating disease known to man, while others see it as a step away from human cloning. While the battle has raged, research is moving ahead, and California has already passed a measure that will give $3 billion in support to stem cell research. But as politics, religion, and the media weigh in on this complex issue, more and more of the scientific reality of stem cell research is getting lost. In the search for the truth about stem cell science, the author has interviewed the scientists whose cutting-edge research is at the very heart of this hot-button issue. The book explains what they have accomplished so far, what they're currently doing, and what... |
 |
Cell of Cells: The Global Race to Capture and Control the Stem Cell by Cynthia Fox (Author) Publication Date is March 26, 2007 |
 |
Human Stem Cell Manual: A Laboratory Guide by Jeanne F. Loring (Editor), Robin L. Wesselschmidt (Editor), Philip H. Schwartz (Editor) Stem cells are self-replicating and undifferentiated, meaning their function is not yet cell, tissue, or organ-specific. Due to the unique nature of these cells, research into their biology and function holds great promise for therapeutic applications through replacement or repair of diseased and damaged cells. This reader-friendly manual provides a practical "hands on" guide to the culture of human embryonic and somatic stem cells. By presenting methods for embryonic and adult lines side-by-side, the authors lay out an elegant and unique path to understanding the science of stem cell practice. The authors begin with a broad-based introduction to the field, and also review legal and regulatory issues and patents. Each experimental strategy is presented with an historical introduction,... |
 |
Essential Stem Cell Methods (Reliable Lab Solutions) by Robert Lanza (Editor), Irina Klimanskaya (Editor) As part of the Reliable Lab Solutions series, this volume offers an abridged and comprehensive update of selected chapters that first appeared in the three-volume stem cell series published in Methods in Enzymology. Currently, stem cells are of great interest to scientists and clinicians due to their unique ability to differentiate into various tissues of the body, making them a promising source of cells for regenerative medicine and drug discovery as well as an excellent model of vertebrate development. Essential Stem Cell Methods features a detailed set of protocols written by experts in the field and hand-selected by the editors to help researchers drive advances in this fast-moving field. The result is a clear set of step-by-step methods which steer the reader... |
 |
Cracking the Stem Cell Code by Christian Drapeau (Author) Are Adult Stem Cells the Prescription for Ultimate Health? "The Coming Revolution in Stem Cells Could Save Your Life" Just the Facts from the Leading Voice of Adult Stem Cell Science When Christian Drapeau first posited that Adult Stem Cells were the very foundation of the body's natural healing system, scientific study in the field was in its infancy. His hypothesis that Adult Stem Cells, created by the bone marrow, flowed to any tissue or organ needing regeneration and morphed into healthy cells of that location, was initially ridiculed by medical science. However, recent studies and a Nobel Prize winning discovery affirm Christian's position which has gained not just momentum but widespread acceptance... |
 |
Stem Cell Research: Medical Applications And Ethical Controversy (The New Biology) by Joseph, Ph.D. Panno (Author) This is an informative reference to the technological advances, applications, and issues of stem cell research. The past few years have seen controversy and debate surrounding stem cell research. Because skin cells have the capability to divide - unlike most of the cells in our body - our skin can heal itself through the division of cells. Scientists have attempted to apply this concept to major organs, trying to see if stem cells can be used to make the repairs that post-mitotic cells cannot. "Stem Cell Research" is a comprehensive and interesting introduction to this popular new science for non-experts. Explaining how stems cells can be obtained from several places, including skin, bone marrow, and most usefully, embryos, this book covers all the fundamental aspects of stem cell... |
 |
The Stem Cell Dilemma: Beacons of Hope or Harbingers of Doom? by Leo Furcht (Author), William Hoffman (Author) TodayÕs scientists are showing us how stem cells create and repair the human body. Unlocking these secrets has become the new Holy Grail of biomedical research. But behind that search lies a sharp divide. Stem cells offer the hope of creating or repairing tissues lost to age, disease, and injury. Yet because of this ability, stem cells hold the potential to incite an international biological arms race. THE STEM CELL DILEMMA will tell you everything you ever wanted to know about stem cells: what they are, how they work, and why their use has become so controversial. We are standing at a scientific crossroads, the likes of which the world has never seen. It is a moment that will change forever the practice of medicine and the future of life as we know it. |
| © 2010 BrightSurf.com |