Source: http://gizmodo.com/researchers-use-circuit-printer-to-make-functional-hear-789602979
Growing replacement organs in a lab
Growing heart tissue in the lab presents an enormous challenge. If the muscle cells aren't precisely arranged to pull along the same axis, the tissue can't do its pumping job. For the 3D cell guidance they needed, researchers at MIT's Draper Lab created thin, micro-perforated sheets of biorubber. They stacked these sheets with a programmable machine from the integrated circuit industry, positioning the pores to create interwoven muscle bundles when seeded with mouse muscle cells and rat neonatal heart cells. By controlling the alignment of the resulting fibers, the researchers can produce tissue that precisely mimics the natural heart.
While several challenges currently prohibit mass-scale production of viable cardiac tissue, the researchers say this unprecedented level of cell growth control opens "a whole new design space." Next, they plan to test the tissue in rats that have suffered heart attacks. And there's a chance that someday, in the not too distant future, nobody will have to die of a broken heart. [MIT Technology Review via KurzweilAI]