ABSTRACT
Injuries of fingertips are common and represent more than 50% of amputation injuries. The digit-tip replantation is a widely accepted treatment for digit amputation but has several limitations and cannot be applied for all amputees. Studies of mammalian digit-tip regeneration hold important implications to identify novel strategies to treat amputees. Mammals are generally considered to have poor regenerative ability, yet the digit tip of humans and rodents can regenerate. After digit-tip amputation, the mass of undifferentiated mesenchymal cells, called blastemal cells, is formed. During digit regeneration, different types of tissues are coordinately formed from blastema. Recent studies have shown that blastemal is composed of multiple types of cells that originate from different cells and nail organ has a critical role in the blastema formation and the subsequent digit-tip regeneration. Here, we will review the blastema formation in mammals, a remarkable phenomenon seen in mice as well as humans after amputation of the digit tip.
