Gene expression of endothelial cells due to interleukin-1 beta stimulation and neutrophil transmigration.

During the inflammatory response, endothelial cell (EC) functions and mechanics change dramatically. To understand these responses, the authors analyzed changes in EC gene expression in an in vitro model of inflammation using cDNA microarrays. After interleukin-1 beta (IL1beta) stimulation, over 2500 genes were differentially expressed, of which approximately 2000 had not been previously identified by microarray studies of IL1beta stimulation in human umbilical vein endothelial cells (HUVECs). Functional grouping of these genes according to gene ontologies revealed genes associated with apoptosis, cell cycle, nuclear factor (NF)-kappa B cascade, chemotaxis, and immune response. Interestingly, claudin-1, known to exist in endothelial cell-cell junctions was up-regulated, but claudin-5 and occludin, which also exist in EC junctions, were down-regulated. Pre-b-cell colony enhancing factor (PBEF), a cytokine which may play a role in regulating endothelial permeability, was also up-regulated following IL1beta stimulation. Neutrophil transmigration across IL1beta-stimulated ECs did not induce changes in EC gene expression as strongly as IL1beta stimulation alone. Nineteen genes after 1 h and 22 genes after 3 h of neutrophil application were differentially expressed. These results indicate that, in terms of transcriptional effects on ECs, neutrophil transmigration is a relatively small perturbation in comparison to the background of large scale changes induced in ECs by cytokine stimulation. Supplementary materials are available for this article. Go to the publisher's online edition of Endothelium for the following free supplementary resources: supplementary figures and tables.