title: Myeloid DAP12-associating lectin (MDL)-1 regulates synovial inflammation and bone erosion associated with autoimmune arthritis.
abstract: DNAX adaptor protein 12 (DAP12) is a trans-membrane adaptor molecule that transduces activating signals in NK and myeloid cells. Absence of functional Dap12 results in osteoclast defects and bone abnormalities. Because DAP12 has no extracelluar binding domains, it must pair with cell surface receptors for signal transduction. There are at least 15 known DAP12-associating cell surface receptors with distinct temporal and cell type-specific expression patterns. Our aim was to determine which receptors may be important in DAP12-associated bone pathologies. Here, we identify myeloid DAP12-associating lectin (MDL)-1 receptor (also known as CLEC5A) as a key regulator of synovial injury and bone erosion during autoimmune joint inflammation. Activation of MDL-1 leads to enhanced recruitment of inflammatory macrophages and neutrophils to the joint and promotes bone erosion. Functional blockade of MDL-1 receptor via Mdl1 deletion or treatment with MDL-1-Ig fusion protein reduces the clinical signs of autoimmune joint inflammation. These findings suggest that MDL-1 receptor may be a therapeutic target for treatment of immune-mediated skeletal disorders.
authors.affiliation: Department of Discovery Research, Schering-Plough Biopharma, Palo Alto, CA 94304, USA.
authors.forename: Barbara
authors.initials: B
authors.lastname: Joyce-Shaikh
authors.forename: Michael E
authors.initials: ME
authors.lastname: Bigler
authors.forename: Cheng-Chi
authors.initials: CC
authors.lastname: Chao
authors.forename: Erin E
authors.initials: EE
authors.lastname: Murphy
authors.forename: Wendy M
authors.initials: WM
authors.lastname: Blumenschein
authors.forename: Iannis E
authors.initials: IE
authors.lastname: Adamopoulos
authors.forename: Paul G
authors.initials: PG
authors.lastname: Heyworth
authors.forename: Svetlana
authors.initials: S
authors.lastname: Antonenko
authors.forename: Edward P
authors.initials: EP
authors.lastname: Bowman
authors.forename: Terrill K
authors.initials: TK
authors.lastname: McClanahan
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Phillips
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Cua
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000276:immunology / Q000502:physiology*; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001172:Arthritis, Rheumatoid / Q000276:immunology / Q000503:physiopathology; D001327:Autoimmune Diseases / Q000276:immunology / Q000628:therapy; D001854:Bone Marrow Cells / Q000276:immunology / Q000502:physiology; D005786:Gene Expression Regulation; D006801:Humans; D007249:Inflammation / Q000276:immunology* / Q000503:physiopathology / Q000628:therapy; D007592:Joint Diseases / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D037181:Lectins, C-Type / Q000235:genetics / Q000276:immunology / Q000502:physiology*; D008565:Membrane Proteins / Q000276:immunology / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D010006:Osteoblasts / Q000502:physiology; D011956:Receptors, Cell Surface / Q000235:genetics / Q000276:immunology / Q000502:physiology*
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D000911:Antibodies, Monoclonal; C509771:CLEC5A protein, human; D037181:Lectins, C-Type; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; C110546:TYROBP protein, human; C484963:Tyrobp protein, mouse