title: Generation of Multilayered 3D Structures of HepG2 Cells Using a Bio-printing Technique.
abstract: OBJECTIVE
  Chronic liver disease is a major widespread cause of death, and whole liver transplantation is the only definitive treatment for patients with end-stage liver diseases. However, many problems, including donor shortage, surgical complications and cost, hinder their usage. Recently, tissue-engineering technology provided a potential breakthrough for solving these problems. Three-dimensional (3D) printing technology has been used to mimic tissues and organs suitable for transplantation, but applications for the liver have been rare.
  
  
  METHODS
  A 3D bioprinting system was used to construct 3D printed hepatic structures using alginate. HepG2 cells were cultured on these 3D structures for 3 weeks and examined by fluorescence microscopy, histology and immunohistochemistry. The expression of liverspecific markers was quantified on days 1, 7, 14, and 21.
  
  
  RESULTS
  The cells grew well on the alginate scaffold, and liver-specific gene expression increased. The cells grew more extensively in 3D culture than two-dimensional culture and exhibited better structural aspects of the liver, indicating that the 3D bioprinting method recapitulates the liver architecture.
  
  
  CONCLUSIONS
  The 3D bioprinting of hepatic structures appears feasible. This technology may become a major tool and provide a bridge between basic science and the clinical challenges for regenerative medicine of the liver.
authors: Department of Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors: Hyeryeon
authors: H
authors: Jeon
authors: Department of Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors: Kyojin
authors: K
authors: Kang
authors: Department of Nature-Inspired Nano Convergence Systems, Korea Institute of Machinery and Materials, Daejeon, Korea.
authors: Su A
authors: SA
authors: Park
authors: Department of Nature-Inspired Nano Convergence Systems, Korea Institute of Machinery and Materials, Daejeon, Korea.
authors: Wan Doo
authors: WD
authors: Kim
authors: Department of Pathology, Hanyang University College of Medicine, Seoul, Korea.
authors: Seung Sam
authors: SS
authors: Paik
authors: Department of Biomedical Science, Graduate School of Biomedical Science Engineering, Hanyang University, Seoul, Korea.
authors: Sang-Hun
authors: SH
authors: Lee
authors: Department of Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors: Jaemin
authors: J
authors: Jeong
authors: Department of Surgery, Hanyang University College of Medicine, Seoul, Korea.
authors: Dongho
authors: D
authors: Choi
mesh_terms: D000464:Alginates; D049109:Cell Proliferation; D020723:Glucuronic Acid; D056945:Hep G2 Cells / Q000166:cytology* / Q000378:metabolism; D006603:Hexuronic Acids; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver / Q000033:anatomy & histology* / Q000378:metabolism; D008856:Microscopy, Fluorescence; D066330:Printing, Three-Dimensional; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D012333:RNA, Messenger; D020723:Glucuronic Acid
keywords: Hep G2 cell; Printing, three-dimensional