Somewhere in Sweden, a few lab mice have human cartilage cells living and growing within their bodies. A team of researchers from Chalmers University of Technology and Sahlgrenska Academy used a CELLINK 3D bioprinter to make hydrogel out of human-derived cartilage cells. They then implanted the gels into six-week-old mice and found "something that begins to resemble cartilage" after 60 days. The researchers are working towards being able to use 3D bioprinting to create body parts for patients who need them. While they're far from achieving that goal, this particular experiment proves that it's a possibility in the future.