title: Gastrointestinal Immune Response to the Shrimp Allergen Tropomyosin: Histological and Immunological Analysis in an Animal Model of Shrimp Tropomyosin Hypersensitivity.
abstract: BACKGROUND
  Shellfish hypersensitivity is among the most common food allergies. A murine model of IgE-mediated shrimp allergy has been established in our laboratory. The aim of this study is to determine the intestinal histological changes and cytokine expression profile of this model sensitized with the major shellfish allergen tropomyosin.
  
  
  METHODS
  Female Balb/c mice orally sensitized and challenged with recombinant tropomyosin were sacrificed. Continuous sections of duodenum, jejunum and ileum were prepared using the Swiss roll technique for histological and immunological analysis. Duodenal epithelial cell apoptosis and migration were examined. mRNA expression of IL-4, IL-6, IL-10, IL-13, IL-18 and IFN-γ in intestinal tissue was measured via RT-PCR.
  
  
  RESULTS
  In tropomyosin-sensitized and challenged mice, an increased number of eosinophils, mast cells and goblet cells was found 24 h after challenge. There were also increased mast cell and goblet cell numbers at 72 h after challenge, but the level of eosinophils decreased. Differences compared with control mice are most prominent at the duodenum compared to the distal regions. In addition, TUNEL assay indicates a significantly higher apoptosis rate in sensitized mice sacrificed 72 h after challenge, and mRNA expression showed a biased Th2/Th1 cytokine profile and a higher level of murine mast cell protease 1.
  
  
  CONCLUSIONS
  This study documented a multitude of histological and immunological changes in the gut in a murine model of shrimp allergy. Even without repetitive intragastric challenge, shrimp tropomyosin induces an increase in the number of inflammatory cells to varying degrees within the small intestine. This model provides an important tool for testing new therapeutic interventions.
authors.affiliation: School of Life Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China.
authors.forename: Yin Fan
authors.initials: YF
authors.lastname: Lam
authors.forename: Ka Kui
authors.initials: KK
authors.lastname: Tong
authors.forename: Kin Ming
authors.initials: KM
authors.lastname: Kwan
authors.forename: Koichi
authors.initials: K
authors.lastname: Tsuneyama
authors.forename: Shang-An
authors.initials: SA
authors.lastname: Shu
authors.forename: Patrick S C
authors.initials: PS
authors.lastname: Leung
authors.forename: Ka Hou
authors.initials: KH
authors.lastname: Chu
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002465:Cell Movement / Q000276:immunology; D049109:Cell Proliferation; D016207:Cytokines / Q000235:genetics; D004195:Disease Models, Animal; D004386:Duodenum / Q000276:immunology; D004804:Eosinophils / Q000166:cytology; D004847:Epithelial Cells / Q000276:immunology; D005260:Female; D005512:Food Hypersensitivity / Q000276:immunology*; D041981:Gastrointestinal Tract / Q000276:immunology*; D020397:Goblet Cells / Q000166:cytology; D007082:Ileum / Q000276:immunology; D007073:Immunoglobulin E / Q000276:immunology; D007249:Inflammation / Q000276:immunology; D007583:Jejunum / Q000276:immunology; D008407:Mast Cells / Q000166:cytology; D051379:Mice; D008807:Mice, Inbred BALB C; D033561:Penaeidae / Q000276:immunology*; D011506:Proteins / Q000276:immunology*; D012333:RNA, Messenger / Q000096:biosynthesis; D012758:Shellfish; D014335:Tropomyosin / Q000276:immunology*
chemical_list: D016207:Cytokines; C102464:Met e 1 allergen; D011506:Proteins; D012333:RNA, Messenger; D014335:Tropomyosin; D007073:Immunoglobulin E