title: Respiratory syncytial virus infection induces expression of the anti-apoptosis gene IEX-1L in human respiratory epithelial cells.
abstract: By means of differential display reverse-transcriptase polymerase chain reaction, increased expression of the mRNA encoding the anti-apoptosis gene IEX-1L was found in respiratory epithelial cells infected with respiratory syncytial virus (RSV). IEX-1L mRNA expression increased 5-7-fold in RSV-infected cells at 72 h after infection but remained unchanged in cells exposed to irradiated, replication-incompetent RSV. Because IEX-1L is reported to protect cells from apoptosis induced by tumor necrosis factor (TNF)-alpha, the effect of TNF-alpha on epithelial cell apoptosis in the context of RSV infection was determined. Epithelial cells were exposed to vehicle, RSV, or irradiated RSV for 72 h, and then TNF-alpha was added to appropriate cultures. Cytochemical staining of cellular DNA with 4,6-diamidino-2-phenylindole demonstrated TNF-alpha-induced apoptosis in 23.4% of control cells but only 5% of RSV-infected cells. These data show that RSV infection protects epithelial cells from TNF-alpha-induced apoptosis and that this effect is temporally associated with IEX-1L gene expression.
authors.affiliation: Department of Pediatrics, Division of Infectious Disease, Upstate Medical University, Syracuse, NY 13210, USA. domachoj@vax.cs.hscsyr.edu
authors.forename: J B
authors.initials: JB
authors.lastname: Domachowske
authors.forename: C A
authors.initials: CA
authors.lastname: Bonville
authors.forename: A J
authors.initials: AJ
authors.lastname: Mortelliti
authors.forename: C B
authors.initials: CB
authors.lastname: Colella
authors.forename: U
authors.initials: U
authors.lastname: Kim
authors.forename: H F
authors.initials: HF
authors.lastname: Rosenberg
mesh_terms: D000256:Adenoviridae / Q000502:physiology; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D004847:Epithelial Cells / Q000378:metabolism / Q000821:virology; D005786:Gene Expression Regulation; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics*; D008562:Membrane Glycoproteins / Q000235:genetics*; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger / Q000032:analysis; D012136:Respiratory Syncytial Viruses / Q000502:physiology* / Q000528:radiation effects; D014407:Tumor Cells, Cultured; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D015854:Up-Regulation
chemical_list: D051017:Apoptosis Regulatory Proteins; C099815:IER3 protein, human; D017874:Immediate-Early Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha