title: Cellular expression and antimicrobial function of a phylogenetically conserved novel histone 1x-like protein on mouse cells: a potential new class of pattern recognition receptor.
abstract: A H1x-like protein (i.e., NCAMP-1) is expressed on the membrane and in GEs from fish NK-like cells. In the present study, we identify the imprinting control region mouse NCAMP-1 ortholog using NCAMP-1 polyclonal antibodies and mAb. Polychromatic flow cytometry revealed NCAMP-1 expression on PBLs (Gr-1(+) PMNs were 21.1% NCAMP-1(+); DX-5(+) NK cells were 12.2% NCAMP-1(+)), mesenteric LN cells (CD11c(+) DCs were 23.2% NCAMP-1(+); Gr-1(+) PMNs were 24.8% NCAMP-1(+); CD21(+) B cells were 17.8% NCAMP-1(+)), and splenocytes (CD11c(+) were 39.6% NCAMP-1(+); Gr-1(+) PMNs were 40.9% NCAMP-1(+); DX-5(+) NK cells were 24.3% NCAMP-1(+); CD21(+) B cells were 28.5% NCAMP-1(+)). Western blot analysis using pNCAMP-1 and GEs from RAW 264.7 cells produced a 32-kDa signal. GEs from RAW 264.7 cells produced a significant reduction in Escherichia coli CFU. This antimicrobial killing activity was inhibited by pretreatment of the extract with (polyclonal) anti-NCAMP-1. Treatment with preimmune serum did not reduce bacterial cell killing. Confocal microscopy using NCAMP-1 and LAMP-1 mAb demonstrated that NCAMP-1 was located on the membrane and in cytosolic vesicles of RAW 264.7 cells and did not appear to colocalize with LAMP-1. NCAMP-1 may participate as a bifunctional protein on cells. It is expressed on the membranes of phagocytic cells, NK cells, and APCs in mice as well as in the granules of macrophages. In phagocytic cells, NCAMP-1 may participate in a nonregulated exocytosis pathway of cellular secretion.
authors.affiliation: Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA.
authors.forename: Donald L
authors.initials: DL
authors.lastname: Evans
authors.forename: Meghan A
authors.initials: MA
authors.lastname: Connor
authors.forename: Lauren D
authors.initials: LD
authors.lastname: Moss
authors.forename: Sarah
authors.initials: S
authors.lastname: Lackay
authors.forename: John H
authors.initials: JH
authors.lastname: Leary
authors.forename: Thomas
authors.initials: T
authors.lastname: Krunkosky
authors.forename: Liliana
authors.initials: L
authors.lastname: Jaso-Friedmann
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004268:DNA-Binding Proteins; D003713:Dendritic Cells / Q000737:chemistry; D004926:Escherichia coli / Q000276:immunology*; D007107:Immune System / Q000737:chemistry / Q000166:cytology*; D007962:Leukocytes / Q000737:chemistry; D008198:Lymph Nodes / Q000737:chemistry / Q000166:cytology; D008264:Macrophages / Q000737:chemistry; D051379:Mice; D009687:Nuclear Proteins / Q000276:immunology*; D010802:Phylogeny; D016601:RNA-Binding Proteins; D051192:Receptors, Pattern Recognition / Q000276:immunology*; D013154:Spleen / Q000737:chemistry / Q000166:cytology
chemical_list: D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; D051192:Receptors, Pattern Recognition; C542907:histone H1x protein, mouse