title: Enhanced complement sensitivity of NK-T cells in murine thymus and spleen associated with presence of serum immunoglobulin.
abstract: In vitro treatment of thymocytes and splenocytes with rabbit complement (C') alone induced significant reductions in the proportion of NK-T cells in murine system. The reduction appeared to be prominent in the thymic NK-T cells compared to that in splenic NK-T cells. No reductions were detected in other populations, such as T, B and NK cells. Thus, NK-T cells lineage-specifically showed the enhanced C' sensitivity. However, NK-T cells in T cell receptor (TCR) transgenic mice of RAG-/- background that lack B cells and antibodies exhibited no C' sensitivity. On the other hand those from the same TCR transgenic mice of RAG intact background that have a normal population of B cells and antibodies showed the C' sensitivity similar to that in normal mice. These findings suggest that the enhanced C' sensitivity observed in the NK-T cell population is associated with the NK-T specific autoantibodies. Indeed, we found that a subset of NK-T cells in the thymus bound mouse immunoglobulins. Similar observations were obtained with several strains of lupus model mice, some of which show a decrease of NK-T cells with aging. Possible roles of the enhanced C' sensitivity of NK-T cells in pathophysiological conditions in various mouse strains including lupus models are discussed.
authors.affiliation: Division of Immunobiology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Onoé
authors.forename: Kazuya
authors.initials: K
authors.lastname: Iwabuchi
authors.forename: Chikako
authors.initials: C
authors.lastname: Iwabuchi
authors.forename: Saori
authors.initials: S
authors.lastname: Tone
authors.forename: Jun
authors.initials: J
authors.lastname: Konishi
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kawakami
authors.forename: Masaharu
authors.initials: M
authors.lastname: Nishimura
authors.forename: Kazunori
authors.initials: K
authors.lastname: Onoé
mesh_terms: D000818:Animals; D003165:Complement System Proteins / Q000494:pharmacology*; D005260:Female; D018398:Homeodomain Proteins / Q000235:genetics / Q000276:immunology; D007136:Immunoglobulins / Q000097:blood; D066298:In Vitro Techniques; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D019463:Mice, Inbred MRL lpr; D008814:Mice, Inbred NZB; D018345:Mice, Knockout; D008822:Mice, Transgenic; D011817:Rabbits; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics; D013154:Spleen / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology
chemical_list: D018398:Homeodomain Proteins; D007136:Immunoglobulins; D016693:Receptors, Antigen, T-Cell, alpha-beta; C064658:RAG-1 protein; D003165:Complement System Proteins