A population of stem cells with strong regenerative potential discovered in deer antlers

Understanding the biology underlying the regeneration of animal limbs, organs, and tissues could be a source of potential applications in medicine. Antlers of deer are a particularly good example because they show complete morphological, structural, and functional regeneration every year, unlike compensatory regeneration in response to injury, for example, as seen in the liver (1, 2). An outstanding characteristic of the antler is the speed of regeneration: They can grow up to 2.75 cm per day and reach up to 15 kg in mass and 120 cm in length in ∼3 months (3). How do deer antlers achieve such rapid and complete regeneration? On page 840 of this issue, Qin et al. (4) identify a population of antler blastema progenitor cells (ABPCs) that are responsible for the antler regenerative cycle. These findings add to the emerging idea that blastema progenitor cells are a common stem cell type in mammalian appendage regeneration.