On February 16, 2016, doctors at Wake Forest Baptist Medical Centre published a paper in Nature Biotechnology explaining how they had 3D-printed body parts that were successfully implanted into rodents. By producing segments of bone, muscles, and cartilage, the team proved that their process can produce tissues of different strengths. Each of the biodegradable, plastic structures has a sponge-like composition that is rife with "micro-channels." These channels ensure that nutrients can permeate the tissue and encourage cell growth. The cells themselves come from a water-based gel in which the body parts are anchored. Once implanted, the body parts successfully fulfilled their functions in rodents, and the future looks bright: researchers are confident that they could print parts at the right scale for humans.