Researchers grow cells in 'paper organs'

Long before scientists test new medicines in animals or people, they study the effects of the substances on cells growing in Petri dishes. However, a 2-D layer of cells is a poor substitute for the much more complex 3-D structure of tissues in organs. Now, researchers reporting in the ACS journal Nano Letters have used a 3-D printer to make paper organs, complete with artificial blood vessels, that they can populate with cells.