111 Facts and Theories of Organ Regeneration in Adults

Abstract

Induced organ regeneration is de novo synthesis of a physiological, or nearly physiological, organ at the same anatomical site as the organ that is being replaced. Regeneration of skin, peripheral nerves, and the conjunctiva have been accomplished using nothing more than biologically active scaffolds (regeneration templates) seeded with epithelial cells; devices for regeneration of the first two organs are in clinical use. Templates appear to function by blocking contraction well as by acting as temporary configurational guides for synthesis of new stroma that resembles that of the organ under replacement. The combined evidence supports a theory which predicts that selective blocking of the adult healing response uncovers part, at least, of the latent fetal response to injury and, in the presence of the appropriate scaffold, eventually leads to organ regeneration. An independent theory suggests that loss of regenerative potential, which is observed during the mammalian fetal-adult transition, is associated with simultaneous acquisition of individual immunocompetence.