Stem cells that give rise to bone and cartilage in mice after birth have been found by two teams.

A group led by Siddhartha Mukherjee and Timothy Wang at Columbia University in New York found that cells at the ends of mouse bones can produce other cells that make bone, cartilage and the spongy tissue in bone marrow. When implanted near a broken bone, these stem cells developed into bone-making cells.

Charles Chan and Michael Longaker at Stanford University in California and their colleagues identified mouse stem cells with similar capabilities, as well as the molecular signals that maintain such cells and guide their development. When combinations of these factors were added to fat tissue in mice along with collagen protein, bone or cartilage formed a month later.

Cell 160, 269–284 ; 285–298 (2015)