title: Model of in vitro healing to test the influence of dedifferentiated Crithmum maritimum cells on dermal repair and epidermal regeneration.
abstract: BACKGROUND
  The aim was to test the influence of dedifferentiated Crithmum maritimum cells (dCMC), totipotent vegetal stem cells, on epidermal regeneration in perfect homeostasis using a skin equivalent (SE) model.
  
  
  METHODS
  SE are prepared by seeding fibroblasts on a collagen-glycosaminoglycan-chitosan dermal substrate (DS) epidermalized by keratinocytes 3 weeks later. The originality of this present study lies in the systemic administration of dCMC from the moment when fibroblasts are seeded in the DS right through to the reconstruction of the SE. The thickness of the epidermis as well as the number of proliferating cells expressing Ki-67 and layers expressing terminal differentiation marker (filaggrin) were compared in the dCMC-treated SE versus an untreated control group.
  
  
  RESULTS
  dCMC accelerated the complete regeneration and differentiation of the epidermis compared to the negative control (35 days instead of 42 days). Histology showed a multilayered, thick and differentiated epithelium after 35 days of culture. The basal and suprabasal layers had increased 4.88 ± 0.41 times versus the negative control (Mann-Whitney U test: p < 0.001). This result was attributed to the greater proliferation of basal cells because the cell numbers expressing the Ki-67 proliferation marker had increased significantly compared to the negative control (Mann-Whitney U test: p < 0.001). Moreover, dCMC allowed the differentiated epithelium to recover because only treated SE expressed the terminal differentiation marker filaggrin.
  
  
  CONCLUSIONS
  Our data show that dCMC enhance epidermal cell grafts by stimulating their regeneration and differentiation in perfect homeostasis. They allow the epidermis to recover its structure for protective functions faster than the negative control.
authors.affiliation: Banque de Tissus et Cellules, Pavillon I, Hôpital Edouard Herriot, HCL, Lyon, France.
authors.forename: C
authors.initials: C
authors.lastname: Lequeux
authors.forename: A
authors.initials: A
authors.lastname: Lhoste
authors.forename: M R
authors.initials: MR
authors.lastname: Rovere
authors.forename: C
authors.initials: C
authors.lastname: Montastier
authors.forename: O
authors.initials: O
authors.lastname: Damour
mesh_terms: D019661:Apiaceae / Q000166:cytology*; D015415:Biomarkers / Q000378:metabolism; D054337:Cell Dedifferentiation; D002454:Cell Differentiation; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D018920:Coculture Techniques; D000078404:Epidermal Cells; D004817:Epidermis / Q000502:physiology*; D005260:Female; D005347:Fibroblasts / Q000502:physiology*; D000091344:Filaggrin Proteins; D006801:Humans; D007381:Intermediate Filament Proteins / Q000378:metabolism; D015603:Keratinocytes / Q000502:physiology*; D019394:Ki-67 Antigen / Q000378:metabolism; D008875:Middle Aged; D008517:Phytotherapy; D017768:Skin, Artificial; D013997:Time Factors; D039901:Totipotent Stem Cells / Q000502:physiology*; D014945:Wound Healing
chemical_list: D015415:Biomarkers; C000717249:FLG protein, human; D000091344:Filaggrin Proteins; D007381:Intermediate Filament Proteins; D019394:Ki-67 Antigen