[textor]

While this is fascinating, I wonder if we could produce the scaffolding itself de novo, and if not, then why? It's not a living thing, just a porous biocompatible structure. At worst, we could grow a lot of skin and process it into scaffolding of arbitrary shape. Or is there some crucial trick, such as remaining chemical signals that guide the development of new cells?

[Nasrudith]

I could see tolerances being an issue there are a lot of fine structures - even if we could shape the protein scaffolds successfully lungs would be far more complex than say a bladder.