Yikes. lab-grown lungs transplanted into rats

I’m not sure whether to be appalled or elated by Harvard Medical School growing rat lungs from living cells and successfully transplanted them into rats. They did it inside rats too, apparently.

The researchers removed rats’ lungs, leaving just the structural “scaffolding” of collagen, blood vessels and airways in place. Immature animal cells were used to “grow” the lungs that were then attached to the scaffolding.