The threat from a heart attack doesn't end with the event itself. Blockage of blood flow to the heart can cause irreversible cell death and scarring. With transplants scarce, half the people who live through a heart attack die within five years. Scientists are trying to address this problem by engineering cardiac tissue to patch up damaged areas.
Now doctoral students Sharon Fleischer and Ron Feiner under the supervision of Dr. Tal Dvir of Tel Aviv University's Department of Molecular Microbiology and Biotechnology and the Center for Nanoscience and Nanotechnology have fabricated fibers shaped like springs that allow engineered cardiac tissue to pump more like the real thing. They reported their findings in the journal Biomaterials in August.
"Until now, when scientists have tried to engineer cardiac tissue, they've used straight fibers to support the contracting cells," says Dr. Dvir. "However, these fibers prevent the contraction of the engineered tissue. What we did was mimic the spring-like fibers that promote contraction and relaxation of the heart muscle. We found that by growing tissues on these fibers, we got more functional tissues."
Springing into action
Cardiac tissue is engineered by allowing cells taken from the hearts of patients or animals to grow on a three-dimensional scaffold, which replaces the extracellular matrix, a collagen grid that naturally supports the cells in the heart. Over time, the cells come together to form a tissue that generates its own electrical impulses and expands and contracts spontaneously. The tissue can then be surgically implanted to replace damaged tissue and improve heart function in patients.
Dr. Dvir's Laboratory for Tissue Engineering and Regenerative Medicine focuses on engineering complex tissues for medical use. When it comes to the heart, the researchers are always looking for ways to build a scaffold that better replicates the extracellular matrix
|Contact: George Hunka|
American Friends of Tel Aviv University