Proinflammatory response of human endothelial cells to Brucella infection.

FERRERO M. C., BREGANTE J., DELPINO M. V., BARRIONUEVO P., FOSSATI C. A., GIAMBARTOLOMEI G. H., BALDI P. C.

MICROBES AND INFECTION

ELSEVIER SCIENCE BV

Año: 2011 vol. 13 p. 852 - 861

1286-4579

Although 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 B. abortus and B. 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 LPS 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 can infect and survive within endothelial cells, in which it induces a proinflammatory response that might be involved in the vascular manifestations of brucellosis.