title: Transplantation of an LGR6+ Epithelial Stem Cell-Enriched Scaffold for Repair of Full-Thickness Soft-Tissue Defects: The In Vitro Development of Polarized Hair-Bearing Skin.
abstract: BACKGROUND
  Recent literature has shown that full-thickness wounds, devoid of the stem cell niche, can subsequently be reconstructed with functional skin elements following migration of the LGR6 epithelial stem cell into the wound bed. In this study, the authors use a variety of LGR6 epithelial stem cell-seeded scaffolds to determine therapeutic utility and regenerative potential in the immediate reconstruction of full-thickness wounds.
  
  
  METHODS
  Isolated LGR6 epithelial stem cells were seeded onto a spectrum of acellular matrices and monitored in both in vitro and in vivo settings to determine their relative capacity to regenerate tissues and heal wounds.
  
  
  RESULTS
  Wound beds containing LGR6 stem cell-seeded scaffolds showed significantly augmented rates of healing, epithelialization, and hair growth compared with controls. Gene and proteomic expression studies indicate that LGR6 stem cell-seeded constructs up-regulate WNT, epidermal growth factor, and angiogenesis pathways. Finally, the addition of stromal vascular fraction to LGR6 stem cell-seeded constructs induces polarized tissue formation, nascent hair growth, and angiogenesis within wounds.
  
  
  CONCLUSIONS
  LGR6 stem cells are able to undergo proliferation, differentiation, and migration following seeding onto a variety of collagen-based scaffolding. In addition, deployment of these constructs induces epithelialization, hair growth, and angiogenesis within wound beds. The addition of stromal vascular fraction to LGR6 stem cell-containing scaffolds initiated an early form of tissue polarization, providing for the first time a clinically applicable stem cell-based construct that is capable of the repair of full-thickness wounds and hair regeneration.
  
  
  METHODS
  Therapeutic, V.
authors.affiliation: Springfield, Ill.; and Baltimore, Md. From the Department of Surgery, Southern Illinois University School of Medicine, Institute for Plastic Surgery, Laboratory for Regenerative Medicine and Applied Sciences; and the Department of Plastic and Reconstructive Surgery, The Johns Hopkins University Hospital.
authors.forename: Denver M
authors.initials: DM
authors.lastname: Lough
authors.forename: Nathan
authors.initials: N
authors.lastname: Wetter
authors.forename: Christopher
authors.initials: C
authors.lastname: Madsen
authors.forename: Joel
authors.initials: J
authors.lastname: Reichensperger
authors.forename: Nicole
authors.initials: N
authors.lastname: Cosenza
authors.forename: Lisa
authors.initials: L
authors.lastname: Cox
authors.forename: Carrie
authors.initials: C
authors.lastname: Harrison
authors.forename: Michael W
authors.initials: MW
authors.lastname: Neumeister
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004847:Epithelial Cells / Q000166:cytology*; D048091:Guided Tissue Regeneration / Q000379:methods*; D018859:Hair Follicle / Q000166:cytology*; D051379:Mice; D008810:Mice, Inbred C57BL; D040901:Proteomics / Q000379:methods; D017695:Soft Tissue Injuries / Q000473:pathology / Q000601:surgery*; D033581:Stem Cell Transplantation / Q000379:methods*; D013234:Stem Cells / Q000166:cytology*; D054457:Tissue Scaffolds; D014945:Wound Healing / Q000502:physiology*
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