title: Proinflammatory response of human endothelial cells to Brucella infection.
abstract: Although vascular pathologies such as vasculitis, endocarditis and mycotic aneurysms have been described in brucellosis patients, the interaction of Brucella with the endothelium has not been characterized. In this study we show that Brucella abortus and Brucella suis can infect and replicate in primary human umbilical vein endothelial cells (HUVEC) and in the microvascular endothelial cell line HMEC-1. Infection led to an increased production of IL-8, MCP-1 and IL-6 in HUVEC and HMEC-1 cells, and an increased expression of adhesion molecules (CD54 in both cells, CD106 and CD62E in HUVEC). Experiments with purified antigens from the bacterial outer membrane revealed that lipoproteins (Omp19) but not lipopolysaccharide mediate these proinflammatory responses. Infection of polarized HMEC-1 cells resulted in an increased capacity of these cells to promote the transmigration of neutrophils from the apical to the basolateral side of the monolayer, and the same phenomenon was observed when the cells were stimulated with live bacteria from the basolateral side. Overall, these results suggest that Brucella spp. can infect and survive within endothelial cells, and can induce a proinflammatory response that might be involved in the vascular manifestations of brucellosis.
authors.affiliation: Instituto de Estudios de la Inmunidad Humoral, Facultad de Farmacia y Bioquímica, UBA, Junín 956, (1113) Buenos Aires, Argentina.
authors.forename: Mariana C
authors.initials: MC
authors.lastname: Ferrero
authors.forename: Julieta
authors.initials: J
authors.lastname: Bregante
authors.forename: M Victoria
authors.initials: MV
authors.lastname: Delpino
authors.forename: Paula
authors.initials: P
authors.lastname: Barrionuevo
authors.forename: Carlos A
authors.initials: CA
authors.lastname: Fossati
authors.forename: Guillermo H
authors.initials: GH
authors.lastname: Giambartolomei
authors.forename: Pablo C
authors.initials: PC
authors.lastname: Baldi
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology; D015703:Antigens, CD / Q000096:biosynthesis; D001425:Bacterial Outer Membrane Proteins / Q000276:immunology; D002003:Brucella abortus / Q000276:immunology* / Q000472:pathogenicity*; D041021:Brucella suis / Q000276:immunology* / Q000472:pathogenicity*; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism*; D042783:Endothelial Cells / Q000276:immunology* / Q000382:microbiology*; D006801:Humans; D008074:Lipoproteins / Q000276:immunology; D009504:Neutrophils / Q000276:immunology; D057705:Transendothelial and Transepithelial Migration
chemical_list: D000942:Antigens, Bacterial; D015703:Antigens, CD; D001425:Bacterial Outer Membrane Proteins; D016207:Cytokines; D008074:Lipoproteins; C097319:OMP19 protein, Brucella abortus