title: Long-term expression pattern of melanocyte markers in light- and dark-pigmented dermo-epidermal cultured human skin substitutes.
abstract: OBJECTIVE
  Transplantation of pigmented tissue-engineered human autologous skin substitutes represents a promising procedure to cover skin defects. We have already demonstrated that we can restore the patient's native light or dark skin color by adding melanocytes to our dermo-epidermal skin analogs. In this long-term study, we investigated if melanocytes in our skin substitutes continue to express markers as BCL2, SOX9, and MITF, known to be involved in survival, differentiation, and function of melanocytes.
  
  
  METHODS
  Human epidermal melanocytes and keratinocytes, as well as dermal fibroblasts from light- and dark-pigmented skin biopsies were isolated and cultured. Bovine collagen hydrogels containing fibroblasts were prepared, and melanocytes and keratinocytes were seeded in a 1:5 ratio onto the gels. Pigmented dermo-epidermal skin substitutes were transplanted onto full-thickness wounds of immuno-incompetent rats and analyzed for the expression of melanocyte markers after 15 weeks.
  
  
  RESULTS
  Employing immunofluorescence staining techniques, we observed that our light and dark dermo-epidermal skin substitutes expressed the same typical melanocyte markers including BCL2, SOX9, and MITF 15 weeks after transplantation as normal human light and dark skin.
  
  
  CONCLUSIONS
  These data suggest that, even in the long run, our light and dark dermo-epidermal tissue-engineered skin substitutes contain melanocytes that display a characteristic expression pattern as seen in normal pigmented human skin. These findings have crucial clinical implications as such grafts transplanted onto patients should warrant physiological numbers, distribution, and function of melanocytes.
authors.affiliation: Tissue Biology Research Unit, University Children's Hospital Zurich, Zurich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Biedermann
authors.forename: Agnieszka S
authors.initials: AS
authors.lastname: Klar
authors.forename: Sophie
authors.initials: S
authors.lastname: Böttcher-Haberzeth
authors.forename: Teresa
authors.initials: T
authors.lastname: Michalczyk
authors.forename: Clemens
authors.initials: C
authors.lastname: Schiestl
authors.forename: Ernst
authors.initials: E
authors.lastname: Reichmann
authors.forename: Martin
authors.initials: M
authors.lastname: Meuli
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D001706:Biopsy; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D005347:Fibroblasts / Q000166:cytology; D006801:Humans; D007150:Immunohistochemistry; D015603:Keratinocytes / Q000166:cytology; D008544:Melanocytes / Q000166:cytology; D051739:Microphthalmia-Associated Transcription Factor / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D051381:Rats; D055758:SOX9 Transcription Factor / Q000378:metabolism; D055757:SOXE Transcription Factors / Q000378:metabolism; D012880:Skin Pigmentation; D016038:Skin Transplantation; D017768:Skin, Artificial; D023822:Tissue Engineering
chemical_list: C000595707:BCL2 protein, human; D015415:Biomarkers; D017077:Culture Media, Conditioned; C497234:MITF protein, human; D051739:Microphthalmia-Associated Transcription Factor; D019253:Proto-Oncogene Proteins c-bcl-2; C527923:SOX10 protein, human; D055758:SOX9 Transcription Factor; C527932:SOX9 protein, human; D055757:SOXE Transcription Factors