title: Notch signaling enhances FcεRI-mediated cytokine production by mast cells through direct and indirect mechanisms.
abstract: Th2-type cytokines and TNF-α secreted by activated mast cells upon cross-linking of FcεRI contribute to the development and maintenance of Th2 immunity to parasites and allergens. We have previously shown that cytokine secretion by mouse mast cells is enhanced by signaling through Notch receptors. In this study, we investigated the molecular mechanisms by which Notch signaling enhances mast cell cytokine production induced by FcεRI cross-linking. FcεRI-mediated production of cytokines, particularly IL-4, was significantly enhanced in mouse bone marrow-derived mast cells by priming with Notch ligands. Western blot analysis showed that Notch signaling augmented and prolonged FcεRI-mediated phosphorylation of MAPKs, mainly JNK and p38 MAPK, through suppression of the expression of SHIP-1, a master negative regulator of FcεRI signaling, resulting in the enhanced production of multiple cytokines. The enhancing effect of Notch ligand priming on multiple cytokine production was abolished by knockdown of Notch2, but not Notch1, and FcεRI-mediated production of multiple cytokines was enhanced by retroviral transduction with the intracellular domain of Notch2. However, only IL-4 production was enhanced by both Notch1 and Notch2. The enhancing effect of Notch signaling on IL-4 production was lost in bone marrow-derived mast cells from mice lacking conserved noncoding sequence 2, which is located at the distal 3' element of the Il4 gene locus and contains Notch effector RBP-J binding sites. These results indicate that Notch2 signaling indirectly enhances the FcεRI-mediated production of multiple cytokines, and both Notch1 and Notch2 signaling directly enhances IL-4 production through the noncoding sequence 2 enhancer of the Il4 gene.
authors.affiliation: Atopy (Allergy) Research Center, Juntendo University School of Medicine, Tokyo 113-8421, Japan; nbnakano@juntendo.ac.jp.
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nakano
authors.affiliation: Atopy (Allergy) Research Center, Juntendo University School of Medicine, Tokyo 113-8421, Japan; Department of Biological Science and Technology, Tokyo University of Science, Tokyo 125-8585, Japan;
authors.forename: Chiharu
authors.initials: C
authors.lastname: Nishiyama
authors.affiliation: Department of Immunology, Juntendo University School of Medicine, Tokyo 113-8421, Japan;
authors.forename: Hideo
authors.initials: H
authors.lastname: Yagita
authors.affiliation: Atopy (Allergy) Research Center, Juntendo University School of Medicine, Tokyo 113-8421, Japan;
authors.forename: Mutsuko
authors.initials: M
authors.lastname: Hara
authors.affiliation: Division of Molecular Pathology, Research Institute for Biomedical Sciences, Tokyo University of Science, Chiba 278-8510, Japan; and Laboratory for Cytokine Regulation, Research Center for Integrative Medical Science, RIKEN Research Center for Allergy and Immunology, RIKEN Yokohama Institute, Yokohama 230-0045, Japan.
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Motomura
authors.affiliation: Division of Molecular Pathology, Research Institute for Biomedical Sciences, Tokyo University of Science, Chiba 278-8510, Japan; and Laboratory for Cytokine Regulation, Research Center for Integrative Medical Science, RIKEN Research Center for Allergy and Immunology, RIKEN Yokohama Institute, Yokohama 230-0045, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Kubo
authors.affiliation: Atopy (Allergy) Research Center, Juntendo University School of Medicine, Tokyo 113-8421, Japan; Department of Immunology, Juntendo University School of Medicine, Tokyo 113-8421, Japan;
authors.forename: Ko
authors.initials: K
authors.lastname: Okumura
authors.affiliation: Atopy (Allergy) Research Center, Juntendo University School of Medicine, Tokyo 113-8421, Japan;
authors.forename: Hideoki
authors.initials: H
authors.lastname: Ogawa
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000276:immunology / Q000378:metabolism; D002460:Cell Line; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation; D000072181:Inositol Polyphosphate 5-Phosphatases; D008024:Ligands; D008407:Mast Cells / Q000276:immunology* / Q000378:metabolism*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D000072183:Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D051881:Receptor, Notch1 / Q000378:metabolism; D051883:Receptor, Notch2 / Q000378:metabolism; D017455:Receptors, IgE / Q000378:metabolism*; D051880:Receptors, Notch / Q000378:metabolism*; D015398:Signal Transduction; D014158:Transcription, Genetic
chemical_list: D016207:Cytokines; D008024:Ligands; D051881:Receptor, Notch1; D051883:Receptor, Notch2; D017455:Receptors, IgE; D051880:Receptors, Notch; D020928:Mitogen-Activated Protein Kinases; D010744:Phosphoric Monoester Hydrolases; D000072181:Inositol Polyphosphate 5-Phosphatases; C000606433:Inpp5d protein, mouse; D000072183:Phosphatidylinositol-3,4,5-Trisphosphate 5-Phosphatases