title: Adipose-derived stem cells seeded on acellular dermal matrix grafts enhance wound healing in a murine model of a full-thickness defect.
abstract: BACKGROUND
  The promotion of wound healing using dermal substitutes has become increasingly widespread, but the outcomes of substitute-assisted healing remain functionally deficient. Adipose-derived stem cells (ASCs) have been investigated widely in regenerative medicine and tissue engineering, and they have the potential to enhance wound healing. In this study, we focused on investigating the effects and mechanism of ASCs combined with an acellular dermal matrix (ADM) to treat full-thickness cutaneous wounds in a murine model.
  
  
  METHODS
  The ADM was prepared from the dorsal skin of nude mice by decellularization by treatment with trypsin followed by Triton X-100. The human ASCs were isolated and cultured from abdominal lipoaspirate. We created a rounded, 8-mm, full-thickness cutaneous wound in nude mice and divided the mice into the following 4 groups: silicon sheet cover only, silicon sheet with spreading ASCs, ADM only, and ASCs seeded on ADM. The granulation thickness was evaluated by histology after 7 days. Further comparisons between the ADM only and ASC-seeded ADM groups were undertaken by assessing the reepithelialization ratio and blood vessel density at postoperative days 9 and 14. Statistical analyses were conducted using Student 2-tailed t test. Immunofluorescent histology and ASC labeling were also performed to identify possible mechanisms.
  
  
  RESULTS
  The ADM was successfully prepared, and the cytometry analysis and differentiation assay provided the characterization of the human ASCs. A marked improvement in granulation thickness was detected in the ADM-ASC group in comparison with other 3 groups. A significantly increased rate of reepithelialization in the ADM-ASC group (80 ± 6%) compared to the ADM only group (60 ± 7%) was noted on postoperative day 9. The blood vessel density was evidently increased in the ADM-ASC group (7.79 ± 0.40 vessels per field) compared to the ADM only group (5.66 ± 0.23 vessels) on day 14. Cell tracking experiments demonstrated that labeled ASCs were colocalized with staining for VEGF or endothelial cell maker vWF after the transplantation of ADM-ASCs on postoperative day 14.
  
  
  CONCLUSIONS
  Adipose-derived stem cells seeded on an ADM can enhance wound healing, promote angiogenesis, and contribute to newly formed vasculature, and VEGF-expressing ASCs can be detected after transplantation. This model could be used to improve the other clinical applications of ASCs and to decipher the detailed mechanism by which ASCs interact with wound tissue.
authors.affiliation: Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Sheng-Ping
authors.initials: SP
authors.lastname: Huang
authors.forename: Chia-Chun
authors.initials: CC
authors.lastname: Hsu
authors.forename: Shun-Cheng
authors.initials: SC
authors.lastname: Chang
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Wang
authors.forename: Shou-Cheng
authors.initials: SC
authors.lastname: Deng
authors.forename: Niann-Tzyy
authors.initials: NT
authors.lastname: Dai
authors.forename: Tim-Mo
authors.initials: TM
authors.lastname: Chen
authors.forename: James Yi-Hsin
authors.initials: JY
authors.lastname: Chan
authors.forename: Shyi-Gen
authors.initials: SG
authors.lastname: Chen
authors.forename: Shih-Ming
authors.initials: SM
authors.lastname: Huang
mesh_terms: D062088:Acellular Dermis; D017667:Adipocytes / Q000166:cytology; D000273:Adipose Tissue / Q000166:cytology*; D000328:Adult; D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D010006:Osteoblasts / Q000166:cytology; D012867:Skin / Q000098:blood supply / Q000293:injuries / Q000473:pathology; D016038:Skin Transplantation; D017768:Skin, Artificial; D033581:Stem Cell Transplantation; D023822:Tissue Engineering; D014945:Wound Healing