title: In vitro and in vivo characterization of silk fibroin/gelatin composite scaffolds for liver tissue engineering.
abstract: OBJECTIVE
  To investigate the cytotoxicity of silk fibroin/gelatin (SF/G) composite scaffolds in vitro as well as their biocompatibility and degradation in vivo.
  
  
  METHODS
  The proliferation and relative growth rate of human hepatic QZG cells grown on different blends of two-dimensional (2-D) SF/G scaffolds were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Flow cytometry was used to evaluate apoptotic rate of QZG cells on different blends of 2-D SF/G scaffolds. The effect of silk protein materials on cell growth was observed by scanning electron microscopy. Three-dimensional (3-D) SF/G scaffolds of three different ratios (diameter 10 mm, thickness 1 mm) were implanted into subcutaneous pockets on male Sprague-Dawley (SD) rats. On the 7th, 14th and 30th day post-implantation, the rats were sacrificed. The scaffold area including the surrounding tissues was retrieved. Hematoxylin and eosin staining was performed for observation under a light microscope.
  
  
  RESULTS
  Significant cell attachment and proliferation on the SF/G scaffolds were observed. As the increased gelatin concentration, SF/G scaffolds became more amenable to cell adhesion. After the subcutaneous implantation of the SF/G scaffolds in SD rats, immunological rejection tests showed only slight inflammation, measured by the presence of inflamed cells on day 7 and 14. By day 30, each scaffold had been completely infiltrated and organized by fibroblasts and inflamed cells. The greater the gelatin concentration in the scaffold, the faster the degradation rate.
  
  
  CONCLUSIONS
  Composite SF/G scaffolds are a promising candidate matrix for implantable bio-artificial livers.
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Li Sha
authors.initials: LS
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Fang
authors.initials: F
authors.lastname: Yin
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Yong Quan
authors.initials: YQ
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Hai Feng
authors.initials: HF
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Yong Zhan
authors.initials: YZ
authors.lastname: Nie
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Jing Bo
authors.initials: JB
authors.lastname: Wang
authors.affiliation: State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Hao
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Dai Ming
authors.initials: DM
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Gastroenterology, Xijing Hospital of Digestive Diseases, The Fourth Military Medical University.
authors.forename: Xin Min
authors.initials: XM
authors.lastname: Zhou
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D017209:Apoptosis; D001672:Biocompatible Materials; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D005349:Fibroins; D005780:Gelatin; D022781:Hepatocytes; D006801:Humans; D008297:Male; D019736:Prostheses and Implants / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
chemical_list: D001672:Biocompatible Materials; D005780:Gelatin; D005349:Fibroins