Rewriting Life

Making Bioartificial Hearts

An ingenious method for making new organs could one day revolutionize medical transplants.

A pig’s heart in formaldehyde has been stripped of its cells using a strong chemical detergent. The extra­cellular matrix left behind will be seeded with cells to produce a new heart.
A rat heart in a bioreactor has been chemically stripped of cells and then repopulated with neonatal cardiac myocytes. Suspended in the bioreactor, the new heart receives nutrients; mechanical and electrical cues train it to beat on its own.
A close-up of the rat heart in the bioreactor shows that it is attached to two catheters responsible for the inflow and outflow of a nutrient solution. The heart is also hooked to two electrodes that train it to contract and expand.