title: Deletion of the murine scavenger receptor CD68.
abstract: Scavenger receptors (ScRs) are a structurally unrelated family of receptors with the ability to bind modified low density lipoprotein (LDL) as well as a broad range of polyanionic ligands. CD68, whose expression is restricted to mononuclear phagocytes, is a unique ScR family member, owing to its lysosome associated membrane protein (LAMP)-like domain and predominant endosomal distribution. Knockout (ko) mice were generated to directly evaluate the role murine CD68 may play in oxidized LDL (Ox-LDL) uptake. However, CD68⁻/⁻ macrophages took up Ox-LDL robustly. Likewise, no defects were observed in the ability of CD68⁻/⁻ mononuclear phagocytes to take up or mount an effective innate response against a number of microbes. Curiously, CD68⁻/⁻ mononuclear phagocytes exhibited a trend toward enhanced antigen presentation to CD4⁺ T-cells, raising the possibility that CD68 may function either to negatively regulate antigen uptake, loading, or major histocompatibility complex class II (MHC-II) trafficking.
authors.affiliation: Department of Microbiology, Columbia University, New York, NY, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Song
authors.forename: Carolyn
authors.initials: C
authors.lastname: Lee
authors.forename: Christian
authors.initials: C
authors.lastname: Schindler
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D015214:Antigens, Differentiation, Myelomonocytic / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D002478:Cells, Cultured; D016207:Cytokines / Q000032:analysis / Q000096:biosynthesis; D011992:Endosomes / Q000378:metabolism*; D005434:Flow Cytometry; D017353:Gene Deletion; D016952:Legionella pneumophila / Q000737:chemistry; D050356:Lipid Metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008077:Lipoproteins, LDL / Q000378:metabolism*; D017737:Macrophages, Peritoneal / Q000166:cytology / Q000378:metabolism*; D051379:Mice; D016133:Polymerase Chain Reaction; D051116:Receptors, Scavenger / Q000172:deficiency* / Q000235:genetics / Q000276:immunology; D000097382:CD68 Molecule
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D016207:Cytokines; D008070:Lipopolysaccharides; D008077:Lipoproteins, LDL; D051116:Receptors, Scavenger; C081026:CD68 protein, mouse; D000097382:CD68 Molecule; C099252:oxidized low density lipoprotein