title: Functional analysis of activating receptor LMIR4 as a counterpart of inhibitory receptor LMIR3.
abstract: The leukocyte mono-Ig-like receptor (LMIR) belongs to a new family of paired immunoreceptors. In this study, we analyzed activating receptor LMIR4/CLM-5 as a counterpart of inhibitory receptor LMIR3/CLM-1. LMIR4 is expressed in myeloid cells, including granulocytes, macrophages, and mast cells, whereas LMIR3 is more broadly expressed. The association of LMIR4 with Fc receptor-gamma among immunoreceptor tyrosine-based activation motif-bearing molecules was indispensable for LMIR4-mediated functions of bone marrow-derived mast cells, but dispensable for its surface expression. Cross-linking of LMIR4 led to Lyn- and Syk-dependent activation of bone marrow-derived mast cells, resulting in cytokine production and degranulation, whereas that of LMIR3 did not. The triggering of LMIR4 and TLR4 synergistically caused robust cytokine production in accordance with enhanced activation of ERK, whereas the co-ligation of LMIR4 and LMIR3 dramatically abrogated cytokine production. Notably, intraperitoneal administration of lipopolysaccharide strikingly up-regulated LMIR3 and down-regulated LMIR4, whereas that of granulocyte colony-stimulating factor up-regulated both LMIR3 and LMIR4 in granulocytes. Cross-linking of LMIR4 in bone marrow granulocytes also resulted in their activation, which was enhanced by lipopolysaccharide. Collectively, these results suggest that the innate immune system is at least in part regulated by the qualitative and quantitative balance of the paired receptors LMIR3 and LMIR4.
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Kumi
authors: K
authors: Izawa
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Jiro
authors: J
authors: Kitaura
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Yoshinori
authors: Y
authors: Yamanishi
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Takayuki
authors: T
authors: Matsuoka
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Toshihiko
authors: T
authors: Oki
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Fumi
authors: F
authors: Shibata
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Hidetoshi
authors: H
authors: Kumagai
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
authors: Hideaki
authors: H
authors: Nakajima
authors: National Institute of Vegetable and Tea Science, National Agriculture Research Organization, 2769 Kanaya, Shizuoka 428-8501, Japan.
authors: Mari
authors: M
authors: Maeda-Yamamoto
authors: R&D Systems, Inc., Minneapolis, Minnesota 55413.
authors: Jeffrey P
authors: JP
authors: Hauchins
authors: Division of Immune Cell Biology, National Institute for Medical Research, London NW7 1AA, United Kingdom.
authors: Victor L J
authors: VLJ
authors: Tybulewicz
authors: Department of Experimental Immunology, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo, Sendai 980-8575, Japan.
authors: Toshiyuki
authors: T
authors: Takai
authors: Division of Cellular Therapy, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan. Electronic address: kitamura@ims.u-tokyo.ac.jp.
authors: Toshio
authors: T
authors: Kitamura
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D003432:Cross-Linking Reagents / Q000494:pharmacology; D005786:Gene Expression Regulation; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D008407:Mast Cells / Q000166:cytology; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008969:Molecular Sequence Data; D017452:Receptors, IgG / Q000378:metabolism; D011971:Receptors, Immunologic / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid
chemical_list: C482560:CLM-1 protein, mouse; C516040:Cd300ld protein, mouse; D003432:Cross-Linking Reagents; D017452:Receptors, IgG; D011971:Receptors, Immunologic; D016178:Granulocyte-Macrophage Colony-Stimulating Factor