Abstract
The ability to activate and regulate stem cells during wound healing and tissue/organ regeneration is a promising field which could bring innovative approaches to regenerative medicine. The regenerative capacity of invertebrates has been well documented, however in mammals, stem cells that drive organ regeneration are rare. Deer antler is unique in providing a mammalian model of complete organ regeneration based on stem cells. The present study investigated the differentially regulated proteins (DRPs) between different antler stem cell populations (n = 3) using 2D-DIGE. Western blotting was used to validate the proteomics results. Comparative proteomics resulted in protein profiles which were similar for the biological replicates but different between the cells derived from two different stem cell niches involved in antler growth/regeneration and cells derived from facial periosteum. Ninety-two up- and down-regulated proteins were identified by MALDI-TOF MS. The work indicates that the epithelial-mesenchymal transition process may participate in the initiation of antler regeneration including the first stage of scar-less wound healing. Cell mobility is also highly regulated during antler regeneration. Energy and nucleotide metabolism may however be less active in antler regeneration as compared to that in antler generation phase. These results provide new insights into the underlying mechanisms of stem cell-based regeneration of mammalian organs.
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•2D-DIGE was used to identify differentially regulated proteins from antler as a large mammalian model of stem cell regulation. Facial periosteum cells as a control were compared to three antler stem cell regions: antlerogenic periosteum cells (APCs) on the frontal bone and responsible of the antler generation of the first year; dormant pedicle periosteum cells (DPPCs) and potentiated pedicle periosteum cells (PPPCs) responsible for antler regeneration of subsequent years.•By adopting the approach of reversed labelling for all the biological replicates, the technical error from using fluorescent dyes was effectively eliminated.•Based on the protein expression profiles the pedicle stem cells (DPPCs and PPPCs) which are geographically adjacent were grouped together.•APCs are in a relatively dormant state prior to the initiation of antler growth and by 2D-DIGE had the most down-regulated proteins with only one enriched pathway of “prostaglandin synthesis and regulation”, suggesting this pathway may play a role in the maintenance of dormant stem cells.•Activation of the epithelial-mesenchymal transition process, known to be involved in embryonic stem cell recruitment, was found to be involved in the initiation of antler regeneration.