Table 2.

Comparisons between antler regeneration and digit tip EpR, stump wound healing and fracture repair in mammals

Antler regeneration	Digit tip EpR	Stump wound healing	Fracture repair
Proliferation of periosteal cells to form a CCC	Extensive histolysis to release the cells for CCC and blastema formation	Proliferation of periosteal cells to form a CCC	Proliferation of periosteal cells to form CCCs
CCC interacts with the fused skin to initiate blastema formation and subsequent regeneration	Cell dedifferentiation and recruitment of progenitor cells; redifferentiation via intramembranous ossification	Fibrous tissue seals the open end of long bone, full thickness skin heals the wound, CCC remodels to bone and then disappears	Two CCCs interact with each other to initiate bridging callus formation and subsequent repair
Interactive partner: enveloping skin	Interactive partner: nail organ	Interactive partner: absence	Interactive partner: opposite callus
Interactive substances: ?	Interactive substances: Wnt factors	Interactive substances: BMP factors	Interactive substances: BMP factors
Growth via modified endochondral ossification	growth via intramembranous ossification	CCC formation via endochondral ossification	Both the CCCs and bridging callus via endochondral ossification
Both nerve and load independent	Nerve independent and load dependent	Nerve independent but load effect not known	Nerve independent and load dependent