Proliferation of Cells From a Mouse Model of Regeneration

The ability to induce limb regeneration in humans is of growing interest in the field of regenerative medicine, particularly due to the increased number of amputees among military veterans. Unfortunately, mammals have limited regenerative capabilities as compared to amphibians, which can re-establish complex structures after traumatic injury. There have been a few clinically documented cases of digit regeneration in children [1], indicating that the potential to regenerate is not completely absent in humans. Mammalian models of epimorphic regeneration is primarily limited to the mouse digit, which has a level-specific response in that amputation at the terminal phalangeal element (P3) results in regeneration, but not at the next more proximal joint (P2) (Figure 1). Recently primary stromal cells were isolated from each of these mouse joints (P3 and P2, respectively) [2], which provides a unique opportunity to utilize in vitro techniques to identify differences in one of the phenotypes prevalent at the amputation plane of a regenerating and non-regenerating region.