The S2 Subunit of QX-type Infectious Bronchitis Coronavirus Spike Protein Is an Essential Determinant of Neurotropism.
Viruses
; 11(10)2019 10 22.
Article
in En
| MEDLINE
| ID: mdl-31652591
ABSTRACT
Some coronaviruses (CoVs) have an extra furin cleavage site (RRKR/S, furin-S2' site) upstream of the fusion peptide in the spike protein, which plays roles in virion adsorption and fusion. Mutation of the S2' site of QX genotype (QX-type) infectious bronchitis virus (IBV) spike protein (S) in a recombinant virus background results in higher pathogenicity, pronounced neural symptoms and neurotropism when compared with conditions in wild-type IBV (WT-IBV) infected chickens. In this study, we present evidence suggesting that recombinant IBV with a mutant S2' site (furin-S2' site) leads to higher mortality. Infection with mutant IBV induces severe encephalitis and breaks the blood-brain barrier. The results of a neutralization test and immunoprotection experiment show that an original serum and vaccine can still provide effective protection in vivo and in vitro. This is the first demonstration of IBV-induced neural symptoms in chickens with encephalitis and the furin-S2' site as a determinant of neurotropism.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Coronavirus Infections
/
Infectious bronchitis virus
/
Encephalitis, Viral
/
Viral Tropism
/
Spike Glycoprotein, Coronavirus
/
Neurons
Limits:
Animals
Language:
En
Journal:
Viruses
Year:
2019
Document type:
Article
Affiliation country:
China