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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.

SUBMITTER: Song L

PROVIDER: S-EPMC3137020 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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Deletion of the murine scavenger receptor CD68.

Song Li L Lee Carolyn C Schindler Christian C

Journal of lipid research 20110513 8

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-LD ...[more]

PMID: 21572087

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