title: Helper function of CD4⁺ lymphocytes in antiviral immunity in ginbuna crucian carp, Carassius auratus langsdorfii.
abstract: Although many recent studies have suggested that CD4(+) helper T cell (Th-cell) functions are well conserved among teleost fishes and mammals, there is little evidence that CD4(+) Th-cells in fish are actually involved in both humoral and cell-mediated immunity during a secondary immune response. In the present study, adoptive transfer using clonal ginbuna crucian carp and crucian carp hematopoietic necrosis virus (CHNV) was used to investigate the functions of CD4(+) cells during humoral and cell-mediated immunity. With regard to humoral immunity, transplanting CHNV-sensitized donor cells, containing CD4(+) cells, into naive fish induced more rapid and stronger antibody production than by transplanting non-sensitized donor cells or sensitized donor cells lacking CD4(+) cells. During cell-mediated immunity, no significant differences were found in recipients that received sensitized cells regardless of whether the donor cells contained CD4(+) cells, although recipients that received both sensitized donor cells (with and without CD4(+) cells) exhibited more efficient cell-mediated cytotoxicity than those that received non-sensitized donor cells. These findings suggest that inducing a secondary antibody response requires CD4(+) cell help, and secondary cell-mediated immunity can be induced both by CD4(+) cells and leukocytes other than CD4(+) cells.
authors.affiliation: Laboratory of Marine Biochemistry, Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka 812-8581, Japan. Electronic address: somamoto@agr.kyushu-u.ac.jp.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Somamoto
authors.affiliation: Department of Applied Aquabiology, National Fisheries University, Shimonoseki, Yamaguchi 759-6595, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Kondo
authors.affiliation: Department of Veterinary Medicine, Nihon University, Fujisawa, Kanagawa 252-0880, Japan.
authors.forename: Teruyuki
authors.initials: T
authors.lastname: Nakanishi
authors.affiliation: Laboratory of Marine Biochemistry, Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka 812-8581, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Nakao
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000637:transplantation / Q000821:virology; D002347:Carps / Q000276:immunology*; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007156:Immunologic Memory; D012209:Rhabdoviridae / Q000276:immunology*; D018353:Rhabdoviridae Infections / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000637:transplantation / Q000821:virology
keywords: Adoptive transfer; CD4; Ginbuna crucian carp; Helper T cell; Virus