3-D bioprinted algae can be harnessed as a sustainable source of oxygen for human cells in engineered vascularized tissues, researchers report November 18 in the journal Matter. They embedded the bioprinted photosynthetic algae, along with human liver-derived cells, in a 3-D hydrogel matrix to create honeycomb-shaped tissues with lobules, similar to the human liver. In the future, the researchers say, the eco-friendly, cost-effective 3-D bioprinting approach may hold potential for applications such as disease modeling, drug development, regenerative and personalized medicine, and even food engineering.