Cellular contribution to supernumerary limbs resulting from the interaction between developing and regenerating tissues in the axolotl

Expression of Sonic hedgehog gene in regenerating newt limb blastemas recapitulates that in developing limb buds

“…Although the process of limb regeneration has remained obscure at the molecular level, substantial progress has recently been made on expressions of morphogenesisrelated genes during embryonic limb development (3)(4)(5)(6)(7)(8)(9)(10). Some evidence suggests that these two processes share mechanisms of growth regulation and pattern formation (11)(12)(13)(14). For example, the expression of homeobox genes during urodele limb regeneration is broadly overlapped with that during limb development (14)(15)(16)(17)(18).…”

“…Muneoka and Bryant attempted to compare patterning mechanisms between the developing and regenerating axolotl limb (11,12). Their results showed that transplanted developing limb buds induce limb duplications on an amputated blastema stump and vice versa, and that cells of both limb buds and blastemas are similarly incorporated in the supernumerary limb.…”

Retinoic acid, local cell-cell interactions, and pattern formation in vertebrate limbs

“…limb side of the confrontation and cells that originated on the regenerating limb side (Muneoka and Bryant, 1984b) (Fig. 2).…”

Biodegradable Polymers as Scaffolds for Tissue Engineering

“…Of particular signifi cance are those fi ndings that indicate that once the regeneration cascade progresses to blastemal stages, the mechanisms controlling growth and pattern formation are the same as those in developing limbs [4] . Thus, the challenge to understanding what might be needed to induce regeneration in humans becomes focused on the developmental signals controlling the transformation of the differentiated stump into a blastema.…”