title: Human parainfluenza virus type 3 up-regulates major histocompatibility complex class I and II expression on respiratory epithelial cells: involvement of a STAT1- and CIITA-independent pathway.
abstract: Human parainfluenza virus type 3 (HPIV3) infection causes severe damage to the lung epithelium, leading to bronchiolitis, pneumonia, and croup in newborns and infants. Cellular immunity that plays a vital role in normal antiviral action appears to be involved, possibly because of inappropriate activation, in the infection-related damage to the lung epithelium. In this study, we investigated the expression of major histocompatibility complex (MHC) class I and II molecules on human lung epithelial (A549) and epithelium-like (HT1080) cells following HPIV3 infection. MHC class I was induced by HPIV3 in these cells at levels similar to those observed with natural inducers such as beta and gamma interferon (IFN-beta and -gamma). MHC class II was also efficiently induced by HPIV3 in these cells. UV-irradiated culture supernatants from infected cells were able to induce MHC class I but not MHC class II, suggesting involvement of released factors for the induction of MHC class I. Quantitation of IFN types I and II in the culture supernatant showed the presence of IFN-beta as the major cytokine, while IFN-gamma was undetectable. Anti-IFN-beta, however, blocked the HPIV3-mediated induction of MHC class I only partially, indicating that viral antigens, besides IFN-beta, are directly involved in the induction process. The induction of MHC class I and class II directed by the viral antigens was confirmed by using cells lacking STAT1, an essential intermediate of the IFN signaling pathways. HPIV3 induced both MHC class I and class II molecules in STAT1-null cells. Furthermore, MHC class II was also induced by HPIV3 in cells defective in class II transactivator, an important intermediate of the IFN-gamma-mediated MHC class II induction pathway. Together, these data indicate that the HPIV3 gene product(s) is directly involved in the induction of MHC class I and II molecules. The induction of MHC class I and II expression by HPIV3 suggests that it plays a role in the infection-related immunity and pathogenesis.
authors.affiliation: Department of Virology, The Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, Ohio 44195, USA.
authors.forename: J
authors.initials: J
authors.lastname: Gao
authors.forename: B P
authors.initials: BP
authors.lastname: De
authors.forename: A K
authors.initials: AK
authors.lastname: Banerjee
mesh_terms: D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D017077:Culture Media, Conditioned; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D004847:Epithelial Cells / Q000166:cytology; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis*; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis*; D006801:Humans; D008168:Lung / Q000166:cytology; D009687:Nuclear Proteins; D010224:Parainfluenza Virus 3, Human / Q000276:immunology*; D050794:STAT1 Transcription Factor; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology*; D014407:Tumor Cells, Cultured; D015854:Up-Regulation; D014771:Virion
chemical_list: D017077:Culture Media, Conditioned; D004268:DNA-Binding Proteins; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; C083728:MHC class II transactivator protein; D009687:Nuclear Proteins; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D015534:Trans-Activators