Answer: scientists have been able to “print” types of human tissue using a 3D printer, but in a significant leap forward by US and Australian researchers they can now make that tissue survive on its own.
Until now a major barrier to them moving from printing tiny sheets of tissue to entire 3D organs is that they hadn’t figured out how to develop the blood vessels that provide cells with nutrients and oxygen, and allow them to excrete waste.
This essential process is called “vascularisation” and is necessary if researchers are to ever prevent cells from dying so they can grow large, transplantable organs.
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