Jocelyn Rice 48 StoriesView profile
Over roughly nine days, a ball of mouse embryonic stem cells (gray) gives rise to a cup-shaped structure (green) with a complex three-dimensional architecture identical to the retina in early development. A tiny sac of cells balloons outward from the clump’s surface; then the sac folds in on itself, with retinal pigment cells on the outside and retinal neurons on the inside.
In the first part of this time-lapse video, an immune cell equipped with a tiny polymer backpack gambols across a microscope slide for some six hours before getting stuck. In the second part of the video, cells with backpacks full of magnetic nanoparticles are tugged toward a magnet, while cells without backpacks stay put.