title: Degradable Chitosan-Collagen Composites Seeded with Cells as Tissue Engineered Heart Valves.
abstract: BACKGROUND
  Degradable collagen-chitosan composite materials have been used to fabricate tissue engineered heart valves. The aims of this study were to demonstrate that the collagen-chitosan composite scaffolds are cytocompatible, and endothelial cells can be differentiated from bone marrow mesenchymal stem cells (BMSCs) when seeded onto the scaffolds. The adhesion and biological activities of the seeded cells were also investigated.
  
  
  METHODS
  Collagen-chitosan composite material was used as the cell matrix, and smooth muscle cells, fibroblasts and BMSCs were used as seed cells. After four weeks of in vitro culture, the smooth muscle cells, fibroblasts, and BMSCs were sequentially seeded into the collagen-chitosan composite material. After four weeks in culture, the cellular density and activity were assessed on segments of the tissue engineered heart valve scaffolds to determine the cell viability and proliferation in the collagen-chitosan composite material.
  
  
  RESULTS
  The tissue engineered heart valves stained positively for both smooth muscle actin and endothelial cell factor VIII, suggesting that the seeded cells were in fact smooth muscle cells, fibroblasts, and endothelial cells. The 6-ketone prostaglandin content, as measured by radioimmunoassay, of the collagen-chitosan cell culture fluid was higher than that of the serum-free medium (P <0.01). Light and electron microscopy showed that the seeded cells had shapes similar to the morphology of smooth muscle cells, fibroblasts, and endothelial cells.
  
  
  CONCLUSIONS
  Endothelial cells can be differentiated from BMSCs when seeded onto the collagen-chitosan composite scaffolds. The seeded cells retained their biological activity after being cultured in vitro and seeded into the collagen-chitosan composite material.
authors.affiliation: Department of Cardiothoracic Surgery, Liaocheng People's Hospital and Liaocheng Clinical School, Taishan Medical University, Liaocheng, Shandong, China. Electronic address: jianhuafu1120@163.com.
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Fu
authors.affiliation: Department of Scientific Research and Education, Liaocheng People's Hospital and Liaocheng Clinical School, Taishan Medical University, Liaocheng, Shandong, China; Cootamundra Medical Centre, Cootamundra, NSW, Australia.
authors.forename: Man
authors.initials: M
authors.lastname: Zhao
authors.affiliation: Department of Cardiothoracic Surgery, Liaocheng People's Hospital and Liaocheng Clinical School, Taishan Medical University, Liaocheng, Shandong, China.
authors.forename: Yan-Rong
authors.initials: YR
authors.lastname: Lin
authors.affiliation: Department of Cardiothoracic Surgery, Liaocheng People's Hospital and Liaocheng Clinical School, Taishan Medical University, Liaocheng, Shandong, China.
authors.forename: Xu-Dong
authors.initials: XD
authors.lastname: Tian
authors.affiliation: Department of Cardiothoracic Surgery, Liaocheng People's Hospital and Liaocheng Clinical School, Taishan Medical University, Liaocheng, Shandong, China.
authors.forename: Ya-Dong
authors.initials: YD
authors.lastname: Wang
authors.affiliation: Department of Cardiothoracic Surgery, Liaocheng People's Hospital and Liaocheng Clinical School, Taishan Medical University, Liaocheng, Shandong, China.
authors.forename: Zhen-Xing
authors.initials: ZX
authors.lastname: Wang
authors.affiliation: Department of Scientific Research and Education, Liaocheng People's Hospital and Liaocheng Clinical School, Taishan Medical University, Liaocheng, Shandong, China; Cootamundra Medical Centre, Cootamundra, NSW, Australia; School of Biomedical Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia. Electronic address: lwang@csu.edu.au.
authors.forename: Le-Xin
authors.initials: LX
authors.lastname: Wang
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D002478:Cells, Cultured; D048271:Chitosan / Q000737:chemistry*; D003094:Collagen / Q000737:chemistry*; D005347:Fibroblasts / Q000145:classification / Q000378:metabolism*; D006351:Heart Valves; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism*; D011817:Rabbits; D023822:Tissue Engineering
chemical_list: D003094:Collagen; D048271:Chitosan
keywords: Cardiac surgery; Collagen-chitosan composite scaffold; Endothelial cell; Fibroblast; Smooth muscle cell; Tissue engineered heart valve