Tiny beating human heart made from scratch
The micro-hearts are around half a millimetre in diameter, and each has its own ventricle-like chamber. It’s the first time that researchers have managed to create three-dimensional heart-like organs in the lab from stem cells alone, without using any sort of scaffold to create the organ’s shape.
First, Zhen Ma of the University of California at Berkeley and his colleagues used ordinary human skin cells to make their induced pluripotent stem cells. Researchers usually use growth factors alone to persuade such stem cells to form the specialised cells of an organ, but Ma’s team used an extra trick next. To mimic the physical forces that usually tell fetal stem cells where they can or can’t grow, they etched tiny “no-go” zones into the wells of the dish to make the cells grow in the right configuration.
“Our model is the first step towards building a heart relying on self-organisation of cells, without any external three-dimensional supporting materials,” says Ma.
The ultimate aim is to build a full-size organ, but the micro-hearts could be used to test the effects of chemicals and drugs on the heart.
Tiny hearts: stem cells make 3D miniature (Image: Zhen Ma)