Navigation Links
New strategy for mending broken hearts?
Date:10/10/2009

DURHAM, N.C. -- By mimicking the way embryonic stem cells develop into heart muscle in a lab, Duke University bioengineers believe they have taken an important first step toward growing a living "heart patch" to repair heart tissue damaged by disease.

In a series of experiments using mouse embryonic stem cells, the bioengineers used a novel mold of their own design to fashion a three-dimensional "patch" made up of heart muscle cells, known as cardiomyocytes. The new tissue exhibited the two most important attributes of heart muscle cells - the ability to contract and to conduct electrical impulses. The mold looks much like a piece of Chex cereal in which researchers varied the shape and length of the pores to control the direction and orientation of the growing cells.

The researchers grew the cells in an environment much like that found in natural tissues. They encapsulated the cells within a gel composed of the blood-clotting protein fibrin, which provided mechanical support to the cells, allowing them to form a three-dimensional structure. They also found that the cardiomyocytes flourished only in the presence of a class of "helper" cells known as cardiac fibroblasts, which comprise as much as 60 percent of all cells present in a human heart.

"If you tried to grow cardiomyocytes alone, they develop into an unorganized ball of cells," said Brian Liau, graduate student in biomedical engineering at Duke's Pratt School of Engineering. Liau, who works in the laboratory of assistant professor Nenad Bursac, presented the results of his latest experiments during the annual scientific sessions of the Biomedical Engineering Society in Pittsburgh.

"We found that adding cardiac fibroblasts to the growing cardiomyocytes created a nourishing environment that stimulated the cells to grow as if they were in a developing heart," Liau said. "When we tested the patch, we found that because the cells aligned themselves in the same direction, they were able to contract like native cells. They were also able to carry the electrical signals that make cardiomyocytes function in a coordinated fashion."

"The addition of fibroblasts in our experiments provided signals that we believe are present in a developing embryo," Liau said. The need for helper cells is not uncommon in mammalian development. For example, he explained, nerve cells need "sheathe" cells known as glia in order to develop and function properly.

Bursac believes that the latest experiments represent a proof-of-principle advance, but said there are still many hurdles to overcome before such patches could be implanted into humans with heart disease.

"While we were able to grow heart muscle cells that were able to contract with strength and carry electric impulses quickly, there are many other factors that need to be considered," Bursac said. "The use of fibrin as a structural material allowed us to grow thicker, three-dimensional patches, which would be essential for the delivery of therapeutic doses of cells. One of the major challenges then would be establishing a blood vessel supply to sustain the patch."

The researchers plan to test their model using non-embryonic stem cells. For use in humans, this is important for many reasons, both scientifically and ethically, Bursac said. Recent studies have demonstrated that some cells from human adults have the ability to be reprogrammed to become similar to embryonic stem cells.

"Human cardiomyocytes tend to grow a lot slower than those of mice," Bursac said. "Since it takes nine months for the human heart to complete development, we need to find a way to get the cells to grow faster while maintaining the same essential properties of native cells."

If they could use a patient's own cells, the patch would also evade an immune system reaction, Bursac added.


'/>"/>

Contact: Richard Merritt
richard.merritt@duke.edu
919-660-8414
Duke University
Source:Eurekalert  

Related biology news :

1. Strategy outlined for growing bioenergy while protecting wildlife
2. IEEE-USA President endorses national innovation strategy
3. Science Coalition commends Presidents strategy for innovation
4. New strategy for inhibiting virus replication
5. A combined tooth-venom arsenal revealed as key to Komodo dragons hunting strategy
6. New therapeutic strategy could target toxic protein in most patients with Huntingtons disease
7. Therapeutic hypothermia is promising strategy to minimize tissue damage
8. RNA research strategy for Europe takes shape
9. Hope for a rabies eradication strategy in Africa
10. Mitochondria could be a target for therapeutic strategy for Alzheimers disease patients
11. GUMC researchers hone in on new strategy to treat common infection
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
New strategy for mending broken hearts?
(Date:1/22/2016)... , Jan. 22, 2016 ... addition of the "Global Biometrics Market ... their offering. --> http://www.researchandmarkets.com/research/p74whf/global_biometrics ... "Global Biometrics Market in Retail Sector ... --> Research and Markets ( ...
(Date:1/18/2016)... , Jan. 18, 2016  Extenua Inc., a ... simplifies the use and access of ubiquitous on-premise ... partnership with American Cyber.  ... experience leading transformational C4ISR and Cyber initiatives in ... the latest proven technology solutions," said Steve ...
(Date:1/11/2016)... , Jan. 11, 2016  higi, the leading ... 10,000 retail locations, web and mobile, today announced ... million from existing investors. --> ... devoted to further innovate higi,s health platform – ... web portal – including expanding services and programs ...
Breaking Biology News(10 mins):
(Date:2/3/2016)... , Feb. 3, 2016 New ... more than $1 million for researchers in ... on health-related research that demonstrates exciting potential.   ... of funding for the New Jersey Health Foundation Research ... members at these educational institutions— Princeton University, Rutgers ...
(Date:2/3/2016)... (PRWEB) , ... February 03, 2016 , ... ... validating a series of potential targets (epitopes) specific to misfolded, propagating strains of ... to create specific monoclonal antibody therapeutics for Alzheimer’s. , Following on from the ...
(Date:2/3/2016)... ... February 03, 2016 , ... Resilinc ... summarizes and analyzes nearly 750 unique supply chain notifications and alerts generated by ... , Supply chain risk management practitioners subscribe to the EventWatch service to receive ...
(Date:2/3/2016)...  Today, Symphony Technology Group (STG) announced the closing ... provider of primary research and analytics-based insight for biopharmaceutical ... a global information and technology services company serving the ... be integrated into IMS Health to form a foundation ... ...
Breaking Biology Technology: