title: The scavenger receptor MARCO is involved in Leishmania major infection by CBA/J macrophages.
abstract: CBA/J mice are resistant to Leishmania major infection but are permissive to L. amazonensis infection. In addition, CBA/J macrophages control L. major but not L. amazonensis infection in vitro. Phagocytosis by macrophages is known to determine the outcome of Leishmania infection. Pattern recognition receptors (PRR) adorning antigen presenting cell surfaces are known to coordinate the link between innate and adaptive immunity. The macrophage receptor with collagenous structure (MARCO) is a PRR that is preferably expressed by macrophages and is capable of binding Gram-positive and Gram-negative bacteria. No research on the role of MARCO in Leishmania-macrophage interactions has been reported. Here, we demonstrate, for the first time, that MARCO expression by CBA/J macrophages is increased in response to both in vitro and in vivo L. major infections, but not to L. amazonensis infection. In addition, a specific anti-MARCO monoclonal antibody reduced L. major infection of macrophages by 30%-40% in vitro. The draining lymph nodes of anti-MARCO-treated mice displayed a reduced presence of immunolabelled parasite and parasite antigens, as well as a reduced inflammatory response. These results support the hypothesis that MARCO has a role in macrophage infection by L. major in vitro as well as in vivo.
authors.affiliation: Centro de Pesquisas Gonçalo Moniz, FIOCRUZ-BA, Brazil.
authors.forename: I N
authors.initials: IN
authors.lastname: Gomes
authors.forename: L C
authors.initials: LC
authors.lastname: Palma
authors.forename: G O
authors.initials: GO
authors.lastname: Campos
authors.forename: J G B
authors.initials: JG
authors.lastname: Lima
authors.forename: T F
authors.initials: TF
authors.lastname: DE Almeida
authors.forename: J P B
authors.initials: JP
authors.lastname: DE Menezes
authors.forename: C A G
authors.initials: CA
authors.lastname: Ferreira
authors.forename: R R Dos
authors.initials: RR
authors.lastname: Santos
authors.forename: G A
authors.initials: GA
authors.lastname: Buck
authors.forename: P A M
authors.initials: PA
authors.lastname: Manque
authors.forename: L S
authors.initials: LS
authors.lastname: Ozaki
authors.forename: C M
authors.initials: CM
authors.lastname: Probst
authors.forename: L A R
authors.initials: LA
authors.lastname: DE Freitas
authors.forename: M A
authors.initials: MA
authors.lastname: Krieger
authors.forename: P S T
authors.initials: PS
authors.lastname: Veras
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology / Q000378:metabolism; D007113:Immunity, Innate; D018320:Leishmania major / Q000276:immunology* / Q000378:metabolism; D007894:Leishmania mexicana / Q000276:immunology / Q000378:metabolism; D007896:Leishmaniasis / Q000276:immunology* / Q000378:metabolism* / Q000469:parasitology / Q000473:pathology; D008198:Lymph Nodes / Q000276:immunology / Q000473:pathology; D017737:Macrophages, Peritoneal / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D008808:Mice, Inbred CBA; D011971:Receptors, Immunologic / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D051116:Receptors, Scavenger / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D015533:Transcriptional Activation; D015854:Up-Regulation
chemical_list: D000913:Antibodies, Protozoan; C092228:Marco protein, mouse; D011971:Receptors, Immunologic; D051116:Receptors, Scavenger