The process of printing the heart involved a biopsy of the fatty tissue that surrounds abdominal organs. Researchers separated the cells in the tissue from the rest of the contents, namely the extracellular matrix linking the cells. The cells were reprogrammed to become stem cells with the ability to differentiate into heart cells; the matrix was processed into a personalized hydrogel that served as the printing “ink.”
The cells and hydrogel were first used to create heart patches with blood vessels and, from there, an entire heart.
“At this stage, our 3D heart is small, the size of a rabbit’s heart,” Dvir said. “But larger human hearts require the same technology.”
Source: 3D-printed heart made using a human patient’s cells – CNN