The chondrocytes were prepared from human iPS cells by a culture method for producing cartilage tissue without from human iPS cell-derived chondrocytes scaffolds. When transplanted into immunodeficient mice and rats, the cartilage prepared from human iPS cells led to tumor formation. The cartilage tissue prepared from human iPS cells was transplanted to damaged articular areas of rats and minipigs by engraftment.

JST news release, Feb. 27, 2015 Akihiro Yamashita et al., “Generation of scaffoldless hyaline cartilaginous tissue from human iPS cells”, Stem Cell Reports