title: Glycosylation is required for coronavirus TGEV to induce an efficient production of IFN alpha by blood mononuclear cells.
abstract: Porcine peripheral blood mononuclear cells (PBMC) are induced to produce interferon alpha (IFN alpha) following in vitro exposure to coronavirus TGEV (transmissible gastroenteritis virus)-infected glutaraldehyde-fixed cell monolayers or to TGEV virions. In the present report, we examined the possibility that glycosylation of viral proteins could play a major role in interactions with PBMC leading to the production of IFN alpha. Con A pretreatment of TGEV-infected cell monolayers before fixation with glutaraldehyde and exposure to PBMC caused a dose-dependent inhibition of IFN alpha induction, implying that masking of carbohydrates at the surface of infected cells lowered IFN-alpha-induction. Similarly, inhibition of N-linked glycosylation by tunicamycin during viral infection of cell monolayers altered their ability to induce IFN alpha. In addition, complete cleavage of 'complex type' oligosaccharides by peptide-N-glycohydrolase F lowered the capacity of TGEV virions to induce IFN alpha. Thus, these findings strongly suggest that glycosylation of the viral proteins, and more precisely the presence of complex-type oligosaccharides, is an important requirement for a completely efficient interaction with PBMC leading to the production of IFN-alpha.
authors.affiliation: Laboratoire de Virologie et d'Immunologie Moléculaires, I.N.R.A., Centre de Recherches de Jouy-en-Josas, France.
authors.forename: B
authors.initials: B
authors.lastname: Charley
authors.forename: L
authors.initials: L
authors.lastname: Lavenant
authors.forename: B
authors.initials: B
authors.lastname: Delmas
mesh_terms: D000581:Amidohydrolases; D000818:Animals; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004306:Dose-Response Relationship, Immunologic; D006031:Glycosylation / Q000187:drug effects; D066298:In Vitro Techniques; D007370:Interferon Type I / Q000096:biosynthesis*; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase; D013552:Swine; D005760:Transmissible gastroenteritis virus / Q000276:immunology*; D014415:Tunicamycin / Q000494:pharmacology; D014764:Viral Proteins / Q000276:immunology / Q000378:metabolism
chemical_list: D007370:Interferon Type I; D014764:Viral Proteins; D003208:Concanavalin A; D014415:Tunicamycin; D000581:Amidohydrolases; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase