title: Crosslinking of the CD69 molecule enhances S100A9 production in activated neutrophils.
abstract: Expression of CD69 on neutrophils and generation of anti-CD69 autoantibodies in patients with rheumatoid arthritis (RA) have been reported. Thus natural ligands for CD69 not yet identified and/or the anti-CD69 autoantibodies possibly affect neutrophils by evoking CD69 signaling, which may further affect joint-composing cells in RA. However, the effect of the CD69 signaling in neutrophils remains largely unclear. To elucidate the issue, we tried to identify proteins affected by the crosslinking of CD69 on neutrophils using a proteomic approach. Specifically, CD69 on granulocyte-macrophage colony stimulating factor (GM-CSF)-activated neutrophils was crosslinked by anti-CD69 monoclonal antibodies, and then intracellular proteins were detected using 2-dimensional electrophoresis and further identified by mass spectrometry and subsequent protein database searching. As a result, we successfully identified multiple proteins that increased their production by the CD69 signaling. Among the proteins, we focused on one of the up-regulated proteins, S100A9 calcium binding protein (S100A9), and investigated proteome changes brought by a recombinant S100A9 in a human synovial sarcoma cell line (SW982), a human chondrosarcoma cell line (OUMS-27), and a human T leukemia cell line (Jurkat). This revealed that the recombinant S100A9 altered proteomes of SW982 and OUMS-27, and to a lesser extent, that of the Jurkat cells. Further, S100A9 induced IL-1beta production from neutrophils and the SW982 cells. These data suggest that unidentified natural ligands for CD69 and/or the anti-CD69 autoantibodies possibly affect joint-composing cell types through the increased production of S100A9 in neutrophils, providing a new insight into functions of CD69 on neutrophils in RA.
authors.affiliation: Department of Bioregulation and Proteomics, Institute of Medical Science, St. Marianna University School of Medicine, Kanagawa, Japan.
authors.forename: Sonoko
authors.initials: S
authors.lastname: Shimada
authors.forename: Manabu
authors.initials: M
authors.lastname: Nakamura
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Kouichiro
authors.initials: K
authors.lastname: Tsutsumi
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Katano
authors.forename: Kayo
authors.initials: K
authors.lastname: Masuko
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yudoh
authors.forename: Izumi
authors.initials: I
authors.lastname: Koizuka
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Kato
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology / Q000378:metabolism*; D001323:Autoantibodies / Q000276:immunology; D040502:Calgranulin B / Q000096:biosynthesis*; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D015180:Electrophoresis, Gel, Two-Dimensional; D005260:Female; D005786:Gene Expression Regulation; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000276:immunology; D006801:Humans; D019169:Jurkat Cells; D037181:Lectins, C-Type; D008024:Ligands; D013058:Mass Spectrometry; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism*; D020543:Proteome / Q000032:analysis; D000099192:CD69 Antigens
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D001323:Autoantibodies; D040502:Calgranulin B; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D037181:Lectins, C-Type; D008024:Ligands; D020543:Proteome; D000099192:CD69 Antigens