Staphylococcus aureus isolates from blood and anterior nares induce similar innate immune responses in endothelial cells
To evaluate the possibility to distinguish virulent from non-virulent isolates, gene expression in human umbilical vein endothelial cells (HUVEC) induced by invasive and colonizing isolates of Staphylococcus aureus was compared. Gene expression in HUVEC was analyzed by microarray analysis after 4 h of infection with Staphylococcus aureus, isolated from healthy nasal carriers (n = 5) and from blood of septic patients (n = 5), to explore possible differences between the groups of bacteria in interaction with HUVEC. All isolates were spa-typed to disclose strain relatedness. Moreover, the isolates were characterized with DNA microarray to determine the presence of virulence genes and to investigate the potential genes of importance in HUVEC interaction. The expression of 41 genes was up-regulated, and four were down-regulated in HUVEC by all isolates. Most of the up-regulated genes encode cytokines, chemokines, interferon-induced proteins, proteins regulating apoptosis and cell proliferation. There was no difference in the gene expression pattern between HUVEC infected with invasive or colonizing isolates. Furthermore, there was no difference in the presence of bacterial virulence genes between the two groups. In conclusion, our data indicate that S. aureus isolates induce comparable expression patterns in HUVEC, irrespective of invasiveness or presence of virulence genes.
Document Type: Research Article
Affiliations: 1: Division of Laboratory Medicine, Department of Clinical Microbiology, County Hospital Ryhov, Jönköping 2: Department of Natural Science and Biomedicine, School of Health Sciences, Jönköping, Sweden 3: Department of Cell Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany 4: Institute of Medical Microbiology, University Hospital Essen, Essen, Germany 5: Division of Clinical Microbiology, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden 6: Institute for Medical Microbiology and Hygiene, Faculty of Medicine ‘Carl Gustav Carus’, Technical University of Dresden, Dresden, Germany
Publication date: 2009-11-01