The Truncated Form of Glycoprotein gp2 of Equine Herpesvirus 1 (EHV-1) Vaccine Strain KyA Is Not Functionally Equivalent to Full-Length gp2 Encoded by EHV-1 Wild-Type Strain RacL11

• DOI: 10.1128/jvi.78.6.3003-3013.2004
• Publication Date: 2004-02-27T21:47:38Z
• Authors: Jens von Einem; Janet Wellington; J. Millar Whalley; Kerstin Osterrieder; Dennis J. O'Calla...; Nikolaus Osterrieder
• Keywords: Mice, Inbred BALB C; 0303 health sciences; Virulence; Molecular Sequence Data; Viral Vaccines; Herpesviridae Infections; Sequence Analysis, DNA; Viral Plaque Assay; Cell Line; 3. Good health; Mice; 03 medical and health sciences; Viral Envelope Proteins; Mutation; Animals; Female; Amino Acid Sequence; Rabbits; Herpesvirus 1, Equid

ABSTRACT Most equine herpesvirus 1 (EHV-1) strains, including the naturally occurring virulent RacL11 isolate, encode a large glycoprotein, gp2 (250 kDa), which is expressed from gene 71. Besides other alterations in viral genome, avirulent strain KyA harbors an in-frame deletion of 1,242 nucleotides To examine contributions variation to virus growth and virulence, mutant viruses expressing full-length or truncated were generated. Western blot analyses demonstrated expression 250-kDa cells infected with harboring 71, whereas 75- 80-kDa was detected gp2. The precursor 250 kDa size its counterpart 80 kDa, as well 42-kDa carboxy-terminal subunit, incorporated into particles. Absence resulted 6-fold reduction extracellular titers 13% plaque diameters, gp2-negative exhibited 55% diameter 51-fold decrease titers. massive defects could be restored by reinsertion but not gene. virulence generated compared murine infection model. lacking apathogenic for BALB/c mice, insertion unable restore virulence. Similarly, replacement genome 71 did result generation virus. From results we conclude that EHV-1 are functionally equivalent cannot compensate action their homologues allogeneic backgrounds.