Already bioprinters are capable of printing small parts, like arteries or knee cartilage. And in the near term, the most likely use is in drug testing-an $11 billion market in itself.

But eventually researchers hope to print a new heart or lung, customized and made entirely from a patients own tissue, limiting the probability of rejection by the body and doing away with long and uncertain waiting periods for donors.
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U.S.-based Organovo introduced the first ever NovoGen bioprinter in 2010, which prints human tissue just like ordinary 3D printers but instead of inert materials they deposit living cells amid a simultaneously printed gel scaffold.