Continued signs of progress in regenerative science from EurekAlert!: "so-called satellite cells in muscle actually include a mix of cells already committed to their muscular fate and others that behave like more versatile stem cells. The cells had widely been considered by scientists as a homogeneous population of dedicated muscle progenitors. Moreover, [researchers] showed that injection of the 'satellite stem cells' into the muscles of mice successfully replenished the animals' regenerative reservoir of cells. ... We've found that there are two types of satellite cell - 90% that are already committed to becoming muscle and another 10% with characteristics normally attributed to stem cells. It's not been shown yet, but these muscle stem cells might even have the capacity to make other tissues, such as bone and fat ... We've also shown that these satellite stem cells, when transplanted into muscle, can repopulate the regenerative cell niche. This is a very significant advance in our understanding of satellite cell biology that will require us to rethink decades of research. It also opens new avenues for therapeutic treatment of muscular diseases."