title: Reorganized small intestine from fetal mouse as an in vitro wound healing model.
abstract: BACKGROUND
  We developed a method for reorganizing the mouse small intestine. In the present study, we investigated whether the reorganized small intestine was morphologically and histochemically differentiated. We also evaluated the reorganized small intestine as an in vitro wound healing model.
  
  
  METHODS
  Fetal mouse small intestines were dispersed into single cells, which were then cultured to a high density. Newly formed small intestine-like organs on a membrane filter were observed by light and electron microscopy. Alkaline phosphatase (ALPase) activity of the epithelium was analyzed. To evaluate the reorganized small intestine as an in vitro wound healing model, a scalpel was used to cut the reorganized intestine on a membrane, and the healing process was morphologically and immunohistochemically examined.
  
  
  RESULTS
  After 6 days in culture, the surface was almost completely coveed with epithelial cells, and villus-like structures were observed. These epithelial cells formed microvilli, and in parallel with this development, ALPase activity of the microvilli increased (from day 4). Twenty-four hours after the cutting, the wound surface was almost completely covered with undifferentiated epithelial cells. The number of acetylated low-density lipoprotein labeled with 1,1,dioctadecyll,3,3,3,3, tetramethyl-indocarbocyanine perchlorate (DiI-Ac-LDL)-positive macrophages increased after cutting. Platelet-derived growth factor (PDGF)-, basic fibroblast growth factor (bFGF)-, matrix metalloproteinase-1 (MMP-1)-positive cells were detected by immunohistochemical staining.
  
  
  CONCLUSIONS
  The reorganized small intestine had a morphologically and histochemically differentiated organoid structure, and was useful as an in vitro model for investigating the process of wound healing.
authors.affiliation: Department of Pediatric Surgery, Saitama Medical School, Saitama 350-0495, Japan.
authors.forename: Hironobu
authors.initials: H
authors.lastname: Yonekawa
authors.forename: Eiko
authors.initials: E
authors.lastname: Murata
authors.forename: Masumi
authors.initials: M
authors.lastname: Akita
authors.forename: Akira
authors.initials: A
authors.lastname: Satomi
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D007150:Immunohistochemistry; D007421:Intestine, Small / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D020782:Matrix Metalloproteinases / Q000378:metabolism; D008567:Membranes, Artificial; D051379:Mice; D008813:Mice, Inbred ICR; D023421:Models, Animal; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D014945:Wound Healing
chemical_list: D008567:Membranes, Artificial; D010982:Platelet-Derived Growth Factor; D016222:Fibroblast Growth Factor 2; D020782:Matrix Metalloproteinases