EHV-1 glycoprotein D (EHV-1 gD) is required for virus entry and cell-cell fusion, and an EHV-1 gD deletion mutant induces a protective immune response in mice.
Insertional mutagenesis was used to construct an equine herpesvirus 1 (EHV-1) mutant in which the open reading frame for glycoprotein D was replaced by a lacZ cassette. This gD deletion mutant (delta gD EHV-1) was unable to infect normally permissive RK cells in culture, but could be propagated in an EHV-1 gD-expressing cell line (RK/gD). Phenotypically complemented delta gD EHV-1 was able to infect RK cells, but did not spread to form syncytial plaques as seen with wild type EHV-1 or with delta gD EHV-1 infection of RK/gD cell cultures. Therefore EHV-1 gD is required for virus entry and for cell-cell fusion. The phenotypically complemented delta gD EHV-1 had very low pathogenicity in a mouse model of EHV-1 respiratory disease, compared to a fully replication-competent EHV-1 reporter virus (lacZ62/63 EHV-1). Intranasal or intramuscular inoculation of mice with delta gD EHV-1 induced protective immune responses that were similar to those elicited in mice inoculated with lacZ62/63 EHV-1 and greater than those following inoculation with UV-inactivated virus.
Csellner
H
H
Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.
Walker
C
C
Wellington
J E
JE
McLure
L E
LE
Love
D N
DN
Whalley
J M
JM
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002459:Cell Fusion; D002478:Cells, Cultured; D003588:Cytopathogenic Effect, Viral; D004195:Disease Models, Animal; D017353:Gene Deletion; D006566:Herpesviridae Infections / Q000276:immunology* / Q000517:prevention & control / Q000821:virology; D004861:Herpesvirus 1, Equid / Q000235:genetics / Q000276:immunology* / Q000378:metabolism / Q000472:pathogenicity* / Q000502:physiology; D008168:Lung / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D009500:Neutralization Tests; D016133:Polymerase Chain Reaction; D011817:Rabbits; D012141:Respiratory Tract Infections / Q000276:immunology / Q000517:prevention & control / Q000821:virology; D014759:Viral Envelope Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism*
D000914:Antibodies, Viral; D014759:Viral Envelope Proteins; C488988:glycoprotein D, Equid herpesvirus 1