Immunity and Wound Healing: Regeneration or Repair?

Tissue injury triggers a highly complex and dynamic process of healing, involving
several coordinated molecular and cellular events to achieve the pre-damage
integrity and homeostasis. The response can occur in the form of regeneration
or repair. Regeneration is variable and results in full replacement of any part
of the body (in some invertebrates), complex structures (eg, limbs), internal
organs (eg, liver), or lost/damaged tissue so that the original architecture and
function are completely restored. In contrast, repair involves fibrotic reactions
leading to scar formation that often impair tissue functionality. The capacity to
perfectly regrow lost appendages or injured tissues varies widely among animal
species. It shows a general gradual loss during ontogenesis and, although the
mechanisms underlying regenerative ability have been largely investigated, the
reasons for the variable potentials remain unclear……