Child’s play (Image: Balkanpix.com/Rex Features)

BUILDING artificial tissue could become child’s play, if Lego-like blocks made of human cells can be assembled into working organs. So far the blocks have been used to build a variety of living 3D shapes that have never before been created on a cell-by-cell basis, such as tubes and solid spheres. The hope is that the bricks will be used to construct artificial tissues for human implantation.

Javier Fernandez and Ali Khademhosseini at the Massachusetts Institute of Technology built the “human Lego” by dipping cells cultured from liver tumours into a polymer called …