Blastemata

Blastemata is the plural form of blastema, a mass of undifferentiated cells capable of growth and regeneration into organs or tissues. In biology, blastemas arise during epimorphic regeneration, a process in which a damaged body part is rebuilt rather than simply repaired. The blastema serves as a progenitor cell pool that can proliferate and later differentiate to form the structures of the missing part.

Cells within a blastema originate from different sources depending on the organism and context. They may derive from dedifferentiated mature cells at the injury site, resident stem or progenitor cells, or a combination of both. The formation and activity of a blastema are influenced by local signaling pathways, the presence of nerves, and the extracellular matrix. In some species, nerve-derived factors are essential for blastema formation and successful regeneration.

Classic examples appear in vertebrates such as salamanders, where limb or tail regeneration involves a limb blastema that eventually differentiates into bone, muscle, nerves, and connective tissue. Similar regenerative programs occur in zebrafish fin regeneration and, in planarians, in which neoblasts form a regenerating blastema. In plants, the term is also used in a related sense to describe a mass of cells from which new organs may arise during regeneration or growth.

Blastemata, as a term, highlights the regenerative potential shared by diverse organisms and remains a focal point for research into tissue formation and regenerative medicine.