Scientists investigating the mechanisms of Down Syndrome (DS) have revealed the earliest developmental changes in embryonic stem cells caused by an extra copy of human chromosome 21 – the aberrant inheritance of which results in the condition. Their study is published online today (Thursday 4 September) in the American Journal of Human Genetics.

Johns Hopkins researchers have discovered the earliest form of human blood stem cells and deciphered the mechanism by which these embryonic stem cells replicate and grow. They also found a surprising biological marker that pinpoints these stem cells, which serve as the progenitors for red blood cells and lymphocytes.

Massachusetts General Hospital (MGH) investigators have found that infusions of a particular bone marrow stem cell appeared to protect gastrointestinal tissue from autoimmune attack in a mouse model. In their report published in the journal Stem Cells, the team from the MGH Center for Engineering in Medicine report that mesenchymal stem cells (MSCs), known to control several immune system activities, allowed the regeneration of the gastrointestinal lining in mice with a genetic mutation leading to multiorgan autoimmune disease.

Researchers have discovered a central molecular switch in fruit fly embryos that opens new avenues for studying the causes of birth defects and cancer in humans. Writing about their study in the Aug. 12 Developmental Cell, scientists at Cincinnati Children's Hospital Medical Center determined the switch to be a main tuning mechanism for instructing cells whether to form sensory nerves or blood cells in different parts of the body.

Adult stem cells originate in a different part of the brain than is commonly believed, and with proper stimulation they can produce new brain cells to replace those lost to disease or injury, a study by UC Irvine scientists has shown.

Montreal, 17 July 2008 – The question of whether insulin-producing cells of the pancreas can regenerate is key to our understanding of diabetes, and to the further development of regenerative therapies against the disease. Dr Rosenberg from the McGill University Health Centre (MUHC) and McGill University together with Dr Bernard Massie from the Centre hospitalier de l'Université de Montréal (CHUM) have just concluded that they can. The results of their study have been published in the July issue of the journal Laboratory Investigation.

Scientists have identified about two dozen genes that control embryonic stem cell fate. The genes may either prod or restrain stem cells from drifting into a kind of limbo, they suspect. The limbo lies between the embryonic stage and fully differentiated, or specialized, cells, such as bone, muscle or fat.

Barcelona, Spain: For the first time in the world scientists have succeeded in developing human embryonic stem cells (hESCs) from a single cell, or blastomere, of a 4-cell stage embryo, the 24th annual conference of the European Society of Human Reproduction and Embryology heard today (Wednesday 9 July). Dr. Hilde Van de Velde, from the Vrije Universiteit Brussel (VUB), Brussels, Belgium, said that their research meant that it might be possible in the future to produce hESC lines at an earlier stage without destroying the embryo.

Researchers have shown that they can put mouse embryonic stem cells to work building the heart, potentially moving medical science a significant step closer to a new generation of heart disease treatments that use human stem cells.

Pu and Zhou tagged the Wt-1 expressing epicardial cells with a fluorescent red protein, then allowed the cells to differentiate. The image shows a descendent cardiomyocyte (green) that carries the same red marker, and another cell that arose from different origins. (The blue stain indicates cell nuclei). Credit: Bin Zhou, MD (Children's Hospital Boston) Researchers at Children's Hospital Boston are continuing to document the heart's earliest origins. Now, they have pinpointed a new, previously unrecognized group of stem cells that give rise to cardiomyocytes, or heart muscle cells. These stem cells, located in the surface of the heart, or epicardium, advance the hope of being able to regenerate injured heart tissue.

Adult stem cells improve healing of broken bones and could eventually serve as a new treatment for the 10 to 20 percent of fractures that fail to heal, according to a new study. The results will be presented Monday, June 16, at The Endocrine Society's 90th Annual Meeting in San Francisco, by Froilan Granero-Molto, PhD, research associate of the University of North Carolina.

Shown above is muscle tissue from a young mouse. On the right side are healthy, new cells created to replace damaged tissue. This ability to regenerate new cells diminishes with age. Credit: Photo courtesy of Morgan Carlson and Irina Conboy, UC Berkeley Old muscle got a shot of youthful vigor in a stem cell experiment by bioengineers at the University of California, Berkeley, setting the path for research on new treatments for age-related degenerative conditions such as muscle atrophy or Alzheimer's and Parkinson's diseases.

Boston, MA-Scientists at Schepens Eye Research Institute have identified specific molecules in the brain that are responsible for awakening and putting to sleep brain stem cells, which, when activated, can transform into neurons (nerve cells) and repair damaged brain tissue. Their findings are published online this week in the Proceedings of the National Academy of Science (PNAS).

When forming attitudes about embryonic stem cell research, people are influenced by a number of things. But understanding science plays a negligible role for many people.

The road to death or differentiation follows a similar course in embryonic stem cells, said researchers at Baylor College of Medicine in Houston in a report that appears online today in the journal Cell Stem Cell.

According to some experts, newly born neuronal stem cells in the adult brain may provide a therapy for brain injury. But if these stem cells are to be utilized in this way, the process by which they are created, neurogenesis, must be regulated.

With improved resolution, tissue-specific molecular markers and precise timing, University of Oregon biologist James A. Weston and colleagues have possibly overturned a long-standing assumption about the origin of embryonic cells that give rise to connective and skeletal tissues that form the base of the skull and facial structures in back-boned creatures from fish to humans.

Research from the University of Southern California (USC) has discovered a new mechanism to allow embryonic stem cells to divide indefinitely and remain undifferentiated. The study, which will be published in the May 22 issue of the journal Nature, also reveals how embryonic stem cell multiplication is regulated, which may be important in understanding how to control tumor cell growth.

While it has long been known that embryonic stem cells have the ability to develop into any kind of tissue-specific cells, the exact mechanism as to how this occurs has heretofore not been demonstrated. Now, researchers at the Hebrew University of Jerusalem and elsewhere have succeeded in graphically revealing this process, resolving a long-standing question as to whether the stem cells achieve their development through selective activation or selective repression of genes.

Stem cell researchers at UCLA were able to grow functioning cardiac cells using mouse skin cells that had been reprogrammed into cells with the same unlimited properties as embryonic stem cells.

The ability to regenerate lost body parts is unevenly distributed among higher organisms. Among vertebrates, some amphibians are able to replace lost limbs completely, while mammals are unable to regenerate complex appendages. The only exception to this rule is the annual replacement of deer antlers. The annual regrowth of these structures is the only example of regeneration of a complete, anatomically complex appendage in a mammal, and antlers are therefore of high interest to regeneration biologists.

A team of researchers led by scientists at Cold Spring Harbor Laboratory have for the first time identified stem cells that allow the pituitary glands of mice to grow even after birth. They found that, in contrast to most adult stem cells, these cells are distinct from those that fuel the initial growth of this important organ. The results suggest a novel way that the hormone-secreting gland may adapt, even in adolescents and adults, to traumatic stress or to normal life changes like pregnancy.