title: IFATS collection: Human adipose-derived stem cells seeded on a silk fibroin-chitosan scaffold enhance wound repair in a murine soft tissue injury model.
abstract: Soft tissue loss presents an ongoing challenge in reconstructive surgery. Local stem cell application has recently been suggested as a possible novel therapy. In the present study we evaluated the potential of a silk fibroin-chitosan (SFCS) scaffold serving as a delivery vehicle for human adipose-derived stem cells (ASCs) in a murine soft tissue injury model. Green fluorescent protein (GFP)-labeled ASCs were seeded on SFCS scaffolds at a density of 1 x 10(5) ASCs per cm(2) for 48 hours and then suture-inlaid to a 6-mm, full-thickness skin defect in 6-week-old male athymic mice. Wound healing was tracked for 2 weeks by planimetry. Histology was evaluated at 2 and 4 weeks. Our data show that the extent of wound closure was significantly enhanced in the ASC-SFCS group versus SFCS and no-graft controls at postoperative day 8 (90% +/- 3% closure vs. 75% +/- 11% and 55% +/- 17%, respectively). Microvessel density at wound bed biopsy sites from 2 weeks postoperative was significantly higher in the ASC-SFCS group versus SFCS alone (7.5 +/- 1.1 vs. 5.1 +/- 1.0 vessels per high-power field). Engrafted stem cells were positive for the fibroblastic marker heat shock protein 47, smooth muscle actin, and von Willebrand factor at both 2 and 4 weeks. GFP-positive stem cells were also found to differentiate into epidermal epithelial cells at 4 weeks postoperative. In conclusion, human adipose-derived stem cells seeded on a silk fibroin-chitosan scaffold enhance wound healing and show differentiation into fibrovascular, endothelial, and epithelial components of restored tissue.
authors.affiliation: Department of Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, 77030, USA.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Altman
authors.forename: Yasheng
authors.initials: Y
authors.lastname: Yan
authors.forename: Nadine
authors.initials: N
authors.lastname: Matthias
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Bai
authors.forename: Carmen
authors.initials: C
authors.lastname: Rios
authors.forename: Anshu B
authors.initials: AB
authors.lastname: Mathur
authors.forename: Yao-Hua
authors.initials: YH
authors.lastname: Song
authors.forename: Eckhard U
authors.initials: EU
authors.lastname: Alt
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D001706:Biopsy; D048271:Chitosan / Q000378:metabolism; D062109:Dermatologic Surgical Procedures; D004195:Disease Models, Animal; D005349:Fibroins / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D051379:Mice; D012038:Regeneration; D047011:Silk / Q000378:metabolism*; D012867:Skin / Q000098:blood supply / Q000473:pathology*; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000166:cytology*; D054457:Tissue Scaffolds; D014945:Wound Healing
chemical_list: D047011:Silk; D005349:Fibroins; D048271:Chitosan