Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tissue-engineered cells transmit electrical signals in animal hearts

18.11.2002


American Heart Association meeting report



Preliminary findings of a study in rats suggests that a person’s own cells might one day replace artificial pacemakers, researchers reported today at the American Heart Association’s Scientific Sessions 2002.

Studies conducted at Children’s Hospital Boston tested the ability of immature skeletal muscle cells to interconnect with heart cells and spread the electrical impulses that keep the heart beating properly.


"The cells have survived in rats for more than a year and they appear to have made connections with cardiac cells," says Douglas B. Cowan, Ph.D., a cell biologist who led the study. "The electrical pathway developed within 10 weeks of implantation.

"Ultimately – maybe a decade down the road – we may be able to use such cell-based technologies in humans to free them from cardiac pacemaker devices," says Cowan, also an assistant professor of anesthesia at Harvard University Medical School in Boston.

Heart contraction starts with an electrical signal that begins in the atrium, a tiny area of the heart’s upper-right chamber. The signal then moves to the other chambers. Damage to the electrical pathway between the atrium and ventricles (the lower chambers) can result in complete heart block, a potentially fatal condition that can only be treated by implanting a cardiac pacemaker.

"We have gathered preliminary evidence that immature skeletal muscle cells can establish a pathway to transmit electrical signals from the heart’s upper right chamber to its lower right chamber," he says.

Heart block is present in about one in 22,000 births, Cowan says. It also can result from open-heart surgery in children, or develop later in life. It’s particularly difficult to treat in infants and children, he says.

"You can’t feed pacemaker wires through the blood vessels of some pediatric patients because the vessels are too small," he explains.

The wire must be coiled inside the chest so it can expand as the child grows, and the pacemakers or their wires often fail, which results in further surgery.

"These patients usually face several repair or replacement operations over the course of their lives," Cowan says.

Researchers extracted small amounts of skeletal muscle from the rats to obtain myoblasts, immature cells destined to become muscle. Unlike mature skeletal muscle cells, myoblasts can make the same proteins that heart muscle cells use to connect with one another to transmit electrical signals. The team used engineered tissue containing about 70 percent myoblasts and 30 percent other cell types, using the connective tissue called collagen. Tissue engineering involves removing cells from the body, manipulating them in the laboratory to create a specific tissue, such as a piece of bone for reconstructive surgery, and implanting it into the patient.

The team created three-dimensional strips of tissue by growing the cell mixtures in small tubes cut in half lengthwise. They then surgically implanted the strips in rat hearts.

"We used a general shape and cells from other animals, but the idea is that eventually we could custom grow tissue for a person using his or her own cells," Cowan notes. By using the patients’ own cells, clinicians may avoid the risk that the immune system will attack the implanted cells, he says.

"The biggest theoretical weakness in this idea was that the proteins required to connect one heart cell to another – called connexins – are usually not expressed in mature skeletal muscle," Cowan says. "Connexins are very important to conduction in the heart. They modify the speed and direction of the electrical signals, and greatly influence how they flow from cell to cell."

"The other question was whether these cells would actually connect with cardiac cells to form an electrical pathway," he says.

Today, the research team reported that the pathway developed and the connexins were present and functioning in the implanted tissue more than one year later.

"We are now using much more sophisticated measurements to confirm this phenomenon and everything at this point shows that the electrical pathway is there," Cowan says.

A lot of work remains before researchers can test the cell-implant technique in humans, Cowan says. "We need rigorous, state-of-the-art experiments to confirm that the tissue is functioning and that the same thing can happen in larger animals."


Co-authors are Yeong-Hoon Choi, M.D.; Christof Stamm, M.D.; Mara Jones, M.S.; Francis X. McGowan, Jr., M.D.; and Pedro J. del Nido, M.D.

Carole Bullock | EurekAlert!
Further information:
http://www.americanheart.org/

More articles from Health and Medicine:

nachricht Custom-tailored strategy against glioblastomas
26.09.2016 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht New leukemia treatment offers hope
23.09.2016 | King Abdullah University of Science and Technology

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: OLED microdisplays in data glasses for improved human-machine interaction

The Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP has been developing various applications for OLED microdisplays based on organic semiconductors. By integrating the capabilities of an image sensor directly into the microdisplay, eye movements can be recorded by the smart glasses and utilized for guidance and control functions, as one example. The new design will be debuted at Augmented World Expo Europe (AWE) in Berlin at Booth B25, October 18th – 19th.

“Augmented-reality” and “wearables” have become terms we encounter almost daily. Both can make daily life a little simpler and provide valuable assistance for...

Im Focus: Artificial Intelligence Helps in the Discovery of New Materials

With the help of artificial intelligence, chemists from the University of Basel in Switzerland have computed the characteristics of about two million crystals made up of four chemical elements. The researchers were able to identify 90 previously unknown thermodynamically stable crystals that can be regarded as new materials. They report on their findings in the scientific journal Physical Review Letters.

Elpasolite is a glassy, transparent, shiny and soft mineral with a cubic crystal structure. First discovered in El Paso County (Colorado, USA), it can also be...

Im Focus: Complex hardmetal tools out of the 3D printer

For the first time, Fraunhofer IKTS shows additively manufactured hardmetal tools at WorldPM 2016 in Hamburg. Mechanical, chemical as well as a high heat resistance and extreme hardness are required from tools that are used in mechanical and automotive engineering or in plastics and building materials industry. Researchers at the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden managed the production of complex hardmetal tools via 3D printing in a quality that are in no way inferior to conventionally produced high-performance tools.

Fraunhofer IKTS counts decades of proven expertise in the development of hardmetals. To date, reliable cutting, drilling, pressing and stamping tools made of...

Im Focus: Launch of New Industry Working Group for Process Control in Laser Material Processing

At AKL’16, the International Laser Technology Congress held in May this year, interest in the topic of process control was greater than expected. Appropriately, the event was also used to launch the Industry Working Group for Process Control in Laser Material Processing. The group provides a forum for representatives from industry and research to initiate pre-competitive projects and discuss issues such as standards, potential cost savings and feasibility.

In the age of industry 4.0, laser technology is firmly established within manufacturing. A wide variety of laser techniques – from USP ablation and additive...

Im Focus: New laser joining technologies at ‘K 2016’ trade fair

Every three years, the plastics industry gathers at K, the international trade fair for plastics and rubber in Düsseldorf. The Fraunhofer Institute for Laser Technology ILT will also be attending again and presenting many innovative technologies, such as for joining plastics and metals using ultrashort pulse lasers. From October 19 to 26, you can find the Fraunhofer ILT at the joint Fraunhofer booth SC01 in Hall 7.

K is the world’s largest trade fair for the plastics and rubber industry. As in previous years, the organizers are expecting 3,000 exhibitors and more than...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Experts from industry and academia discuss the future mobile telecommunications standard 5G

23.09.2016 | Event News

ICPE in Graz for the seventh time

20.09.2016 | Event News

Using mathematical models to understand our brain

16.09.2016 | Event News

 
Latest News

How to merge two black holes in a simple way

26.09.2016 | Physics and Astronomy

Australian technology installed on world’s largest single-dish radio telescope

26.09.2016 | Physics and Astronomy

New mechanisms uncovered explaining frost tolerance in plants

26.09.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>