title: Teleost IL-6 promotes antibody production through STAT3 signaling via IL-6R and gp130.
abstract: Teleost IL-6 is upregulated after antigen stimulation; therefore, we hypothesized that fish IL-6 contributes to antibody production during immune responses against infections. To verify this hypothesis, we first cloned IL-6R and gp130 in fugu (Takifugu rubripes) in the present study. The membrane and soluble forms of IL-6R were identified by the identification of cDNA clones of IL-6R homologues. Three STAT3-docking sites were found in the intracellular region of fugu gp130. Expression analysis showed that fugu IL-6R and gp130 were expressed in mIgM(+) B cells, suggesting that fugu B cells are stimulated by IL-6. Recombinant fugu IL-6 (rfIL-6) increased the gene expression of secretory antibodies by mIgM(+) B cells in vitro. The rfIL-6 and soluble form of rfIL-6R activated STAT3 phosphorylation in the B cells and a cultured cell line transfected with fugu gp130. These results indicate that fugu IL-6 enhances antibody production in the B-cell lineage via gp130 and STAT3 signaling.
authors.affiliation: Faculty of Marine Biosciences, Fukui Prefectural University, Obama, Fukui 917-0003, Japan.
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Kaneda
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Odaka
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Suetake
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tahara
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Miyadai
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000917:Antibody Formation; D001402:B-Lymphocytes / Q000378:metabolism; D003001:Cloning, Molecular; D050822:Cytokine Receptor gp130 / Q000378:metabolism*; D029941:Fish Proteins / Q000378:metabolism*; D006801:Humans; D015850:Interleukin-6 / Q000276:immunology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D019947:Receptors, Interleukin-6 / Q000378:metabolism*; D050796:STAT3 Transcription Factor / Q000378:metabolism*; D016415:Sequence Alignment; D015398:Signal Transduction; D023741:Takifugu / Q000276:immunology*
chemical_list: D029941:Fish Proteins; D015850:Interleukin-6; D019947:Receptors, Interleukin-6; D050796:STAT3 Transcription Factor; D050822:Cytokine Receptor gp130