title: Effects of glycosylation on antigenicity and immunogenicity of classical swine fever virus envelope proteins.
abstract: Classical swine fever virus (CSFV) harbors three envelope glycoproteins (E(rns), E1 and E2). Previous studies have demonstrated that removal of specific glycosylation sites within these proteins yielded attenuated and immunogenic CSFV mutants. Here we analyzed the effects of lack of glycosylation of baculovirus-expressed E(rns), E1, and E2 proteins on immunogenicity. Interestingly, E(rns), E1, and E2 proteins lacking proper post-translational modifications, most noticeable lack of glycosylation, failed to induce a detectable virus neutralizing antibody (NA) response and protection against CSFV. Similarly, no NA or protection was observed in pigs immunized with E1 glycoprotein. Analysis of E(rns) and E2 proteins with single site glycosylation mutations revealed that detectable antibody responses, but not protection against lethal CSFV challenge is affected by removal of specific glycosylation sites. In addition, it was observed that single administration of purified E(rns) glycoprotein induced an effective protection against CSFV infection.
authors.affiliation: Department of Pathobiology and Veterinary Science, University of Connecticut, Storrs, CT 06269, USA. boris.gavrilov@uconn.edu
authors.forename: Boris K
authors.initials: BK
authors.lastname: Gavrilov
authors.forename: Kara
authors.initials: K
authors.lastname: Rogers
authors.forename: Ignacio J
authors.initials: IJ
authors.lastname: Fernandez-Sainz
authors.forename: Lauren G
authors.initials: LG
authors.lastname: Holinka
authors.forename: Manuel V
authors.initials: MV
authors.lastname: Borca
authors.forename: Guillermo R
authors.initials: GR
authors.lastname: Risatti
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000096:biosynthesis / Q000276:immunology*; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000276:immunology*; D002460:Cell Line; D006691:Classical Swine Fever / Q000276:immunology*; D006692:Classical Swine Fever Virus / Q000276:immunology*; D006031:Glycosylation; D007114:Immunization; D016133:Polymerase Chain Reaction; D011499:Protein Processing, Post-Translational; D011994:Recombinant Proteins; D018411:Spodoptera; D013552:Swine; D014759:Viral Envelope Proteins / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D015678:Viral Structural Proteins / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D011994:Recombinant Proteins; D014759:Viral Envelope Proteins; D015678:Viral Structural Proteins; C087086:glycoprotein E2, classical swine fever virus; C107842:protein E1, Classical swine fever virus