Stem cell-derived human heart tissue beating

Replica heart tissue throbs (shown above slower than actual speed) with a rhythm similar to that of a true heartbeat. Credit: Lemme et al./Stem Cell Rep.

Stem cells

Heart-in-a-dish dances to the beat

Bioengineered tissue mimics the upper chambers of the heart.

Researchers have created models of human-heart tissue that beat just like the heart’s upper chambers.

Most artificially produced heart-muscle cells share characteristics with cells from the heart’s lower chambers, or ventricles. Thomas Eschenhagen at the University Medical Center Hamburg-Eppendorf in Germany and his colleagues sought to make cells similar to those of the organ’s upper chambers, known as the atria.

The group started with cells that had been reprogrammed into an embryonic-like state, and transformed them into heart-muscle cells. The researchers added retinoic acid, which is a derivative of vitamin A, to nudge the cells towards development into atrial-like tissue. The cells were then cultured in a fibrous, protein-based gel that allowed the tissue to grow in three dimensions.

The resulting 3D structures mimicked atrial heart muscle in the force of their contractions, their reaction to drugs and other properties. The scientists say that the beating structures could serve as models for drug development and for studies of how the heart functions.