title: Enhanced proliferation and functions of in vitro expanded human hair follicle outer root sheath cells by low oxygen tension culture.
abstract: BACKGROUND
  Human hair follicle outer root sheath (hORS) cells are known to contain hair follicle stem cells and play an important role in healing large size wounds, and thus can serve as the cell source for skin engineering. This study investigated the effect of low oxygen tension culture on hORS cell proliferation potential and functional maintenance during in vitro expansion.
  
  
  METHODS
  Spared postsurgery scalp tissues were donated by 15 patients aged 20-45 (13 men and 2 women) and were randomly divided into three groups, and isolated hORS cells were combined into three pooled cell samples. They were cultured either in 4% O(2) or 21% O(2) and were analyzed for cell proliferation, colony forming efficiency (CFE), and their ability in forming engineered skin in vitro.
  
  
  RESULTS
  The results showed that freshly isolated hORS cells expressed CD200 (22.88±8.76), cytokeratin 15 (CK15) (62.57±4.72), CD29 (22.53±2.49/strong and 29.80±4.09/dim), and CD49f (28.07±15.76/strong and 49.73±5.65/dim). When exposed in 4% O(2), hORS cells proliferated significantly faster than the cells in 21% O(2) for the first three passages (p<0.05), could better maintain cobblestone morphology, respectively, generate 3.63-folds more and 23.26-folds more cell yields after one and three passages. Additionally, enhanced CFE with significantly higher total and holoclone colony numbers were found in the 4% O(2) group than in the 21% O(2) group (p<0.05) for the first three passages along with better maintained CK15 expression. Furthermore, hORS cells expanded in 4% O(2) could form better epidermal structure of in vitro engineered skin comparing to the skin engineered by the control cells.
  
  
  CONCLUSIONS
  The low oxygen culture method of hORS cells is simple, low cost, less labor intensive, and less biosafety concern, which may potentially be applied in skin engineering and clinical application.
authors.affiliation: Department of Plastic and Reconstructive Surgery, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering Research, Shanghai, P R China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Xia
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.forename: Wenjie
authors.initials: W
authors.lastname: Zhang
authors.forename: Guangdong
authors.initials: G
authors.lastname: Zhou
authors.forename: Yilin
authors.initials: Y
authors.lastname: Cao
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
mesh_terms: D000328:Adult; D000941:Antigens / Q000378:metabolism; D018929:Cell Culture Techniques / Q000379:methods*; D049109:Cell Proliferation; D005260:Female; D005347:Fibroblasts / Q000166:cytology; D005434:Flow Cytometry / Q000379:methods; D018859:Hair Follicle / Q000473:pathology*; D006801:Humans; D053569:Keratin-15 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000737:chemistry*; D012867:Skin / Q000473:pathology; D023822:Tissue Engineering / Q000379:methods*; D014945:Wound Healing
chemical_list: D000941:Antigens; D053569:Keratin-15; D010100:Oxygen