Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers identify master cardiac stem cell

24.11.2006
Progenitors develop into three types of heart cells, could be ideal for regenerative studies

Researchers from the Massachusetts General Hospital (MGH) Cardiovascular Research Center have discovered what appears to be a master cardiac stem cell, capable of differentiating into the three major types of cells that make up the mammalian heart. In their report appearing in the Dec. 15 issue of the journal Cell and receiving early online release, the scientists describe identifying these progenitor cells in mice, cloning single cells from embryonic stem cells, and showing that these cloned cells can differentiate into cardiac muscle, smooth muscle or endothelial cells.

"These cells offer new prospects for drug discovery and genetically based models of human disease. They also give us a new paradigm for cardiac development, in which a single multipotent cell can diversify into both muscle and endothelial lineages," says Kenneth R. Chien, MD, director of the MGH Cardiovascular Research Center (CVRC) and senior author of the Cell paper. "They additionally suggest a novel strategy for the regeneration of cardiac muscle, coronary arterial and pacemaker cells." Chien also leads the cardiovascular program at the Harvard Stem Cell Institute, one of the study's supporters.

Several populations of embryonic cells that develop into the heart and associated structures have previously been indentified. It has been thought that the three types of cells that make up the heart itself – the contracting cardiac muscle cells and the smooth muscle and endothelial cells that make up blood vessels – all develop from different cellular progenitors. Two major groups of cardiac muscle progenitors, called the first and second field, have been identified.

In 2005, Chien's team, then at the University of California at San Diego, described finding a group of cardiac muscle progenitors called isl1+ cells in heart tissue from newborn rats, mice and humans. The islet-1 protein, for which isl1+ progenitors are named, is known to be expressed in cells from the second cardiac field, which generate the structures on the right side of the heart. The current study was designed to investigate whether islet-1 expressing cells give rise to more than just cardiac muscle cells.

In a variety of experiments, the researchers first identified a small population of embryonic islet-1-expressing cells that can develop into working cardiac muscle, smooth muscle, pacemaker cells and the endothelial cells lining the major vessels of the heart and the coronary arteries. Starting with embryonic stem cells from mice, they were able to generate these multipotent embryonic isl1+ progenitor cells (MIPCs) – the parental cells that give rise to the postnatal progenitor cells identified in the 2005 study – and to clone and expand their population in vitro.

The team's in vivo study of mouse embryos found within primitive cardiac tissues a small group of cells expressing islet-1 and two other important proteins called Nkx2.5 and flk1. The researchers cultured and cloned those cells and found they could differentiate into all three cardiac cells types, verifying that they were MIPCs. Expression of the Nkx2.5 and flk1 genes seems to play a role in the process by which the cells 'decide' their developmental fate.

"We think these are authentic cardiac stem cells that are responsible for forming the diverse cell types of the heart, although other cells also contribute to some structures," says Chien. "These MIPCs may be excellent candidates for cardiac muscle regeneration studies, without the risk of tumor formation posed by embryonic stem cells or the limited effectiveness seen in studies using other cell types.

"It now appears that cardiac cells develop in the same way that blood cells do, with a master stem cell giving rise to the entire range of cells. The search is now on for the hormones that trigger expansion of MIPCs, which would be analogous to the factors that drive blood formation." Chien was recently named the Sanders Professor of Basic Science at Harvard Medical School.

The same issue of Cell contains an accompanying article from the Children's Hospital Boston laboratory of Stuart Orkin, MD, and the Harvard Stem Cell Institute describing the discovery in the first cardiac field of progenitor cells expressing the Nkx2.5 protein that can generate both cardiac and smooth muscle cells. Sean Wu, MD, PhD, the first author of that paper, has recently joined the MGH-CVRC where he and Chien's team will follow up these seminal findings, including clarifying any developmental relationship between the two types of progenitor cells.

Sue McGreevey | EurekAlert!
Further information:
http://www.mgh.harvard.edu/

More articles from Life Sciences:

nachricht Bacteria as pacemaker for the intestine
22.11.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>