Traditionally, cell cultures have been made in a 2-D petri dish. Problem is, cells cultured flat don't act quite the same as cells made in 3-D cultures. So instead, researchers from Rice University and Nano3D Biosciences started using magnetic levitation to get a 3-D culture. And now, using that tech, they've arranged four types of cells into super-realistic lung tissue. [Perfect timing! -ed.]

This is how the levitation works. Inert, magnetic nanoparticles are inserted into the cells, and researchers can manipulate them by using magnets--in this case, a magnetic "pen." That ability to tinker with the cells opens the door for more complicated cultures. The four-layered replication, of the lung's bronchiole tissue, is made from endothelial cells, smooth muscle cells, fibroblasts, and epithelial cells.