title: The effect of kiwifruit (Actinidia deliciosa) cysteine protease actinidin on the occludin tight junction network in T84 intestinal epithelial cells.
abstract: Actinidin, a kiwifruit cysteine protease, is a marker allergen for genuine sensitization to this food allergen source. Inhalatory cysteine proteases have the capacity for disruption of tight junctions (TJs) enhancing the permeability of the bronchial epithelium. No such properties have been reported for allergenic food proteases so far. The aim was to determine the effect of actinidin on the integrity of T84 monolayers by evaluating its action on the TJ protein occludin. Immunoblot and immunofluorescence were employed for the detection of occludin protein alterations. Gene expression was evaluated by RT-PCR. Breach of occludin network was assessed by measuring transepithelial resistance, blue dextran leakage and passage of allergens from the apical to basolateral compartment. Actinidin exerted direct proteolytic cleavage of occludin; no alteration of occludin gene expression was detected. There was a reduction of occludin staining upon actinidin treatment as a consequence of its degradation and dispersion within the membrane. There was an increase in permeability of the T84 monolayer resulting in reduced transepithelial resistance, blue dextran leakage and passage of allergens actinidin and thaumatin-like protein from the apical to basolateral compartment. Opening of TJs by actinidin may increase intestinal permeability and contribute to the process of sensitization in kiwifruit allergy.
authors.affiliation: Department of Experimental Oncology, Institute for Oncology and Radiology of Serbia, Pasterova 14, 11000 Belgrade, Serbia.
authors.forename: Milena
authors.initials: M
authors.lastname: Cavic
authors.affiliation: Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 16, 11000 Belgrade, Serbia.
authors.forename: Milica M
authors.initials: MM
authors.lastname: Grozdanovic
authors.affiliation: Center for Laser Microscopy, Faculty of Biology, University of Belgrade, Studentski trg 3, 11000 Belgrade, Serbia.
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Bajic
authors.affiliation: Department of Experimental Oncology, Institute for Oncology and Radiology of Serbia, Pasterova 14, 11000 Belgrade, Serbia.
authors.forename: Radmila
authors.initials: R
authors.lastname: Jankovic
authors.affiliation: Center for Laser Microscopy, Faculty of Biology, University of Belgrade, Studentski trg 3, 11000 Belgrade, Serbia.
authors.forename: Pavle R
authors.initials: PR
authors.lastname: Andjus
authors.affiliation: Department of Biochemistry, Faculty of Chemistry, University of Belgrade, Studentski trg 16, 11000 Belgrade, Serbia. Electronic address: mgavrov@chem.bg.ac.rs.
authors.forename: Marija
authors.initials: M
authors.lastname: Gavrovic-Jankulovic
mesh_terms: D029042:Actinidia / Q000201:enzymology* / Q000276:immunology; D045744:Cell Line, Tumor; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D005512:Food Hypersensitivity / Q000276:immunology; D006801:Humans; D015151:Immunoblotting; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000166:cytology / Q000187:drug effects*; D018613:Microscopy, Confocal; D062793:Occludin / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D059748:Proteolysis; D019108:Tight Junctions / Q000187:drug effects*; D014178:Translocation, Genetic
chemical_list: D062793:Occludin; D010940:Plant Proteins; C003427:thaumatin protein, plant; D003546:Cysteine Endopeptidases; C018745:actinidain
keywords: Actinidia deliciosa; Actinidin; Food allergy; Kiwifruit; Occludin; Tight junction