Beating patch of cells could heal broken hearts

Researchers have now engineered tissue that closely mimics natural heart muscle that beats, not only in a lab dish but also when implanted into animals.

Nasim Annabi, Ph.D said that repairing damaged hearts could help millions of people around the world live longer, healthier lives.

To engineer complex 3-D tissues, researchers at the Brigham and Women's Hospital and Harvard Medical School in Boston and the University of Sydney in Australia were able to combine a novel elastic hydrogel with microscale technologies to create an artificial cardiac tissue that mimics the mechanical and biological properties of the native heart.

To tackle the challenge of engineering heart muscle, Ali Khademhosseini, Ph.D., who is at Harvard Medical School, and Annabi have been working with natural proteins that form gelatin-like materials called hydrogels.

His group has found that they can tune these hydrogels to have the chemical, biological, mechanical and electrical properties they want for the regeneration of various tissues in the body.

But there was one way in which the materials didn't resemble human tissue. Like gelatin, early versions of the hydrogels would fall apart, whereas human hearts are elastic.

The elasticity of the heart tissue plays a key role for the proper function of heart muscles such as contractile activity during beating. So, the researchers developed a new family of gels using a stretchy human protein aptly called tropoelastin. That did the trick, giving the materials much needed resilience and strength.