A Heart of Stone: Cardiac Fibroblasts Turn to Bone in Calcified Hearts

The identity of the cells and molecular events driving deleterious calcification of heart muscle remains elusive. In this issue of Cell Stem Cell, Pillai et al. (2017) report that cardiac fibroblasts respond to injury by adopting an osteogenic cell fate and creating damaging calcific deposits, which can be prevented by inhibiting the activated mineralization process. The identity of the cells and molecular events driving deleterious calcification of heart muscle remains elusive. In this issue of Cell Stem Cell, Pillai et al. (2017) report that cardiac fibroblasts respond to injury by adopting an osteogenic cell fate and creating damaging calcific deposits, which can be prevented by inhibiting the activated mineralization process.