Scientists grew beating, disembodied hearts. Recipe: Take a dead rat heart, filter out its cells, and use the remaining structural "matrix" as a framework for heart cells taken from newborn rats. Apply electrical stimulus and circulatory pressure. Results: The hearts began to beat and were successfully transplanted into unrelated rats, whose cells began to colonize them. Old idea: Regenerate your heart inside your body. New idea: Grow a new heart in the lab, then put it in your body. Hype: 1) We can grow whatever organs you need. 2) Unlike donor organs, they'll be compatible with your immune system, since they'll be made from your cells. Criticisms: 1) The study involved rats, not people. 2) The recolonized vessels might cause clots. 3) If it works in people, it'll take us at least a decade to get there. 4) And recipients might still need immunosuppressive drugs. (Related: 1) A military project to regrow lost body parts using matrix. 2) Lab-grown blood vessels. 3) Lab-grown livers. 4) Lab-grown bladders. 5) Lab-grown breast implants. 6) Lab-grown meat. 7) Growing organs through embryo farming.)
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