Interleukin-8 mRNA synthesis and protein secretion are continuously up-regulated by respiratory syncytial virus persistently infected cells

• Published in: Cellular immunology 2005, Vol.233 (1), p.61-71
• Main Authors: Tirado, Rocio, Ortega, Arturo, Sarmiento, Rosa Elena, Gómez, Beatríz
• Format: Article
• Language: English
• Subjects: Antigens, Surface - analysis; Antigens, Surface - physiology; Antigens, Viral - analysis; Cell Line, Tumor; Culture Media, Conditioned - chemistry; Culture Media, Conditioned - pharmacology; Culture Media, Conditioned - radiation effects; Enzyme-Linked Immunosorbent Assay; Epithelial Cells - drug effects; Epithelial Cells - metabolism; Epithelial Cells - virology; Extra-cellular RSV proteins; Fractional Precipitation; Gene Expression - drug effects; Hot Temperature; Human airway epithelial cells; Humans; Immunoprecipitation; Interleukin-1 - antagonists & inhibitors; Interleukin-1 - metabolism; Interleukin-8; Interleukin-8 - genetics; Interleukin-8 - secretion; Polyethylene Glycols - chemistry; Respiratory syncytial virus; Respiratory Syncytial Virus, Human - metabolism; Respiratory Syncytial Virus, Human - radiation effects; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - genetics; RNA, Messenger - metabolism; Trypsin - metabolism; Ultraviolet Rays; Up-regulation; Up-Regulation - drug effects; Viral Envelope Proteins - metabolism; Viral Envelope Proteins - pharmacology; Viral Fusion Proteins - metabolism; Viral Fusion Proteins - pharmacology; Viral Proteins - analysis; Viral Proteins - immunology
• ISSN: 0008-8749; 1090-2163
• DOI: 10.1016/j.cellimm.2005.04.003

The aim of this study was to investigate whether respiratory syncytial virus persistence regulates interleukin 8 (IL-8) mRNA synthesis and protein secretion in a human lung epithelial cell line (A549). Therefore, we established RSV persistence in these cells (A549per) and determined the levels of interleukin-8 mRNA by RT-PCR and of protein through ELISA. Interleukin-8 mRNA synthesis and protein secretion were continuously up-regulated in A549per cells during passages and in A549 cells that had been incubated with supernatants (cA549per) obtained from A549per passages. These results suggested that the enhancement of interleukin-8 was stimulated either by the presence of the RSV genome in the cell or by soluble mediator(s) induced by RSV, which, in turn, increased interleukin-8 mRNA synthesis and protein secretion. Soluble RSV F and G proteins were identified as mediators. Moreover, interleukin-8 enhancement was observed after 1-min incubation with the soluble mediators, thus suggesting that interleukin-8 up-regulation was triggered by receptor–ligand interaction.