Primary cultures of human umbilical chord vein endothelial cells: a biological model for studying enterococcal infection mechanisms.

Abstract

Although enterococcus bacteria are normal human intestinal flora, they rank as the third most common pathogen involved in hospital acquired infections. Generally, these bacteria are considered extracellular pathogens; however, an increasing number of reports indicate invasiveness to epithelial cell lines and macrophages. Despite their importance as nosocomial infection agents in patients suffering bacteremias and endocarditis, their interaction with endothelial cells has not been fully described. Herein, the nosocomial Enterococcus faecalis isolate Ef2890 from a hospitalized patient was exposed to cultured human venous endothelial cells from the umbilical chord. When the primary cell cultures were inoculated with Ef2890 and treated with bactericidal antibiotics to kill extracellular and adhered bacteria, intracellular bacteria were recovered and plated 4 h post-infection. These observations indicate that cell cultures provide a valuable biological model to study interactions between endothelium and enterococci.