title: Elevated proportion of natural killer T cells in periodontitis lesions: a common feature of chronic inflammatory diseases.
abstract: Although periodontitis is a chronic inflammatory disease caused by a group of so-called periodontopathic bacteria, autoimmune mechanisms have also been implicated in the disease process. Recently, a unique subset of lymphocytes designated natural killer (NK) T cells expressing the Valpha24JalphaQ invariant T cell receptor (TCR) has been reported to have a regulatory role in certain autoimmune diseases. Therefore, we investigated the proportion of the invariant Valpha24JalphaQ TCR within the Valpha24 T cell population in periodontitis lesions and gingivitis lesions using single-strand conformation polymorphism methodology. NK T cells were identified with a specific JalphaQ probe whereas the total Valpha24 TCR was identified using an internal Calpha probe. NK T cells were a significant proportion of the total Valpha24 population both in periodontitis lesions and to a lesser extent in gingivitis lesions but not in the peripheral blood of either periodontitis patients or nondiseased controls. Using immunohistochemistry, some of Valpha24(+) cells in the periodontitis lesions seemed to associate with CD1d(+) cells, which are specific antigen-presenting cells for NK T cells. Although the mechanism underlying the elevation of NK T cells in periodontitis and in gingivitis lesions remains unclear, it can be postulated that NK T cells are recruited to a play regulatory role in the immune response to bacterial infection.
authors: Department of Periodontology, Faculty of Dentistry, Niigata University, 5274, Gakkocho-Dori 2-ban-cho, Niigata 951-8514, Japan. kaz@dent.niigata-u.ac.jp
authors: K
authors: K
authors: Yamazaki
authors: Y
authors: Y
authors: Ohsawa
authors: H
authors: H
authors: Yoshie
mesh_terms: D000328:Adult; D018949:Antigens, CD1 / Q000032:analysis; D055610:Antigens, CD1d; D002908:Chronic Disease; D002999:Clone Cells; D014644:Genetic Variation; D005881:Gingiva / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007249:Inflammation / Q000473:pathology; D007694:Killer Cells, Natural / Q000276:immunology / Q000473:pathology*; D008875:Middle Aged; D010518:Periodontitis / Q000473:pathology*; D011948:Receptors, Antigen, T-Cell / Q000097:blood / Q000235:genetics / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology*
chemical_list: D018949:Antigens, CD1; D055610:Antigens, CD1d; C526877:CD1D protein, human; D011948:Receptors, Antigen, T-Cell