Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UCSD team discovers specialized, rare heart stem cells in newborns

10.02.2005


Potential for replacing damaged tissue

The first evidence of cardiac progenitor cells – rare, specialized stem cells located in the newborn heart of rats, mice and humans – has been shown by researchers at the University of California, San Diego (UCSD) School of Medicine. The cells are capable of differentiation into fully mature heart tissue. Called isl1+ cells, these cardiac progenitor cells are stem cells that have been programmed to form heart muscle during fetal growth. Until this new discovery, the cells were thought to be absent after birth. However, the UCSD team discovered a small number of the specialized stem cells remained embedded in a region of the newborn heart called the atrium. They also determined that the cells could be expanded into millions of progenitor cells by growing them on a layer of neighboring heart cells called fibroblasts.

Published in the February 10, 2005 issue of the journal Nature, the research identified the isl1+ progenitor cells in the tissue of newborn rats and mice, and then in heart tissue taken from five newborn human babies undergoing surgery for congenital heart defects. Study author Sylvia Evans, Ph.D., a member of the UCSD Institute of Molecular Medicine (IMM) and professor of pharmacology, and co-first author Alessandra Moretti, Ph.D., IMM member, explained that the cells are programmed to become spontaneously beating cardiac muscle cells simply by exposure to other neighboring heart cells.



And, since these rare cardiac progenitor cells are found in regions of the atrium that are normally discarded during routine cardiac surgery, the discovery raises the possibility that an individual could receive their own cardiac stem cells to correct a wide spectrum of pediatric cardiac diseases, according to co-first authors Moretti and Karl-Ludwig Laugwitz, M.D., a Heisenberg-Scholar of the German Research Foundation.

"Conceptually, these cells could provide a cell-therapy based approach to pediatric cardiac disease, which is new for cardiology," said the study’s senior author, Kenneth Chien, M.D., Ph.D., director of the UCSD Institute of Molecular Medicine. "Traditionally, pediatric cardiologists and cardiac surgeons have relied on mechanical devices, human and synthetic tissue grafts, and artificial and animal derived valves to surgically repair heart defects. While progenitor cells won’t grow a whole new heart, our research has shown that they can spontaneously become cells from specific parts of the heart by simple co-exposure to other heart cells, which could augment existing surgical procedures. If the cells maintain pacemaker function when placed in the intact heart, they might serve as biological pacemakers for infants born with heart block, which could also be valuable."

After the isl1+ cells were found in newborn rats, the UCSD team used sophisticated genetic methods to tag the progenitor cells in living embryonic tissue and in the newborn heart of mice. With these techniques, they were able to show that the isl1+ progenitor cells were spontaneously able to form cardiac muscle tissue.

"Furthermore, the cardiac muscle cells formed were totally mature and had the complete array of function that one would expect in completely differentiated heart tissue," said the study’s co-first author Jason Lam, Ph.D. candidate in the IMM. The cells exhibited contractility, pumping ability, the correct electrical physiology and normal heart structure. In addition, the progenitor cells coupled with neighboring cardiac muscle cells with resulting normal electrical heart beats.

"Another important discovery was the ability to expand the few cells found in a newborn heart, into millions of cells in lab culture dishes," Laugwitz said. "This implies that the isl1+ cells potentially could be harvested from an individual’s heart tissue, multiplied in a laboratory setting, then re-implanted into the patient. Furthermore, the developmental lineage marker which identifies undifferentiated cardiogenic precursors suggests the feasibility of isolating isl1+ cardiac progenitors from mouse and human embryonic stem cell systems during cardiogenesis."

"We think that these cells normally play an important role in the remodeling of the heart after birth, when the newborn heart no longer relies upon the mother’s circulation and oxygenation," Chien said. "We believe the isl1+ progenitor cells are left over from fetal development so that they can insure the closure of any existing small heart defects and the formation of a completely mature heart in newborns."

The UCSD team noted in the Nature paper that the next research steps with the isl1+ cells will be cellular transplantation in living animals to study their role in endogenous repair after cardiac injury.

In addition to Chien, Evans, Lauagwitz, Moretti and Lam, study authors included Peter Gruber, M.D., Ph.D., Children’s Hospital of Philadelphia; Yinhong Chen, M.D., Ph.D., Sarah Woodard, B.S., Lizhu Lin, Ph.D., and Chen-Leng Cai, Ph.D., UCSD Institute of Molecular Medicine; Min Min Lu, Ph.D., Department of Medicine, University of Pennsylvania; and Michael Reth, Ph.D., Max-Planck Institut fur Immunbiologie, Universitat Freiburg, Freiburg, Germany.

Sue Pondrom | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>