Inhibition of henipavirus infection by Nipah virus attachment glycoprotein occurs without cell-surface downregulation of ephrin-B2 or ephrin-B3.
Nipah virus (NiV) and Hendra virus (HeV) are newly identified members of the family Paramyxoviridae and have been classified in the new genus Henipavirus based on unique genetic characteristics distinct from other paramyxoviruses. Transgenic cell lines were generated that expressed either the attachment protein (G) or the fusion protein (F) of NiV. Functional expression of NiV F and G was verified by complementation with the corresponding glycoprotein, which resulted in the development of syncytia. When exposed to NiV and HeV, expression of NiV G in Crandall feline kidney cells resulted in a qualitative inhibition of both cytopathic effect (CPE) and cell death by both viruses. RT-PCR analysis of surviving exposed cells showed a complete absence of viral positive-sense mRNA and genomic negative-sense viral RNA. Cells expressing NiV G were also unable to fuse with cells co-expressing NiV F and G in a fluorescent fusion inhibition assay. Cell-surface staining for the cellular receptors for NiV and HeV (ephrin-B2 and ephrin-B3) indicated that they were located on the surface of cells, regardless of NiV G expression or infection by NiV. These results indicated that viral interference can be established for henipaviruses and requires only the expression of the attachment protein, G. Furthermore, it was found that this interference probably occurs at the level of virus entry, as fusion was not observed in cells expressing NiV G. Finally, expression of NiV G by either transient transfection or NiV infection did not alter the cell-surface levels of the two known viral receptors.
Sawatsky
Bevan
B
Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada.|National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada.
Grolla
Allen
A
National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada.
Kuzenko
Nina
N
Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada.|National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada.
Weingartl
Hana
H
National Centre for Foreign Animal Disease, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada.|Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada.
Czub
Markus
M
Department of Medical Microbiology, University of Manitoba, 730 William Avenue, Winnipeg, MB R3E 0W3, Canada.|National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, 1015 Arlington Street, Winnipeg, MB R3E 3R2, Canada.
D000818:Animals; D002415:Cats; D002460:Cell Line; D003588:Cytopathogenic Effect, Viral / Q000187:drug effects; D015536:Down-Regulation; D036388:Ephrin-B2 / Q000378:metabolism*; D036389:Ephrin-B3 / Q000378:metabolism*; D015726:Giant Cells; D006168:Guinea Pigs; D045404:Hendra Virus / Q000472:pathogenicity*; D006801:Humans; D045405:Nipah Virus / Q000378:metabolism*; D014759:Viral Envelope Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D014762:Viral Interference
D036388:Ephrin-B2; D036389:Ephrin-B3; C510755:F protein, Nipah virus; D014759:Viral Envelope Proteins; C116204:attachment protein G