Genetic Variation of the VP1 Gene of the Virulent Duck Hepatitis A Virus Type 1 (DHAV-1) Isolates in Shandong Province of China
10.1007/sl2250-012-3255-8
- Author:
Jiming GAO
;
Junhao CHEN
;
Xingkui SI
;
Zhijing XIE
;
Yanli ZHU
;
Xingxiao ZHANG
;
Shujing WANG
;
Shijin JIANG
- Publication Type:Journal Article
- Keywords:
Duck hepatitis A virus type 1 (DHAV-1);
Embryonal lethal dose (ELD50);
Lethal dose (LD50);
Cross-neutralization tests;
Virion protein 1 (VP1)
- From:
Virologica Sinica
2012;27(4):248-253
- CountryChina
- Language:Chinese
-
Abstract:
To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1(DHAV-1) isolates,the virulence,cross neutralization assays and the complete sequence of the virion protein 1(VP1) gene of nine virulent DHAV-1 strains,which were isolated from infected ducklings with clinical symptoms in Shandong province of China in 2007-2008,were tested.The fifth generation duck embryo allantoic liquids of the 9 isolates were tested on 12-day-old duck embryos and on 7-day-old ducklings for the median embryonal lethal doses(ELD50s) and the median lethal doses(LD50s),respectively.The results showed that the ELD5s of embryonic duck eggs of the 9 DHAV-1 isolates were between 1.9 × 106/mL to 1.44 × 107/mL,while the LD50s were 2.39 × 105/mL to 6.15 × 106/mL.Cross-neutralization tests revealed that the 9 DHAV-1 isolates were completely neutralized by the standard serum and the hyperimmune sera against the 9 DHAV-1 isolates,respectively.Compared with other virulent,moderate virulent,attenuated vaccine and mild strains,the VP1 genes of the 9 strains shared 89.8％-99.7％ similarity at the nucleotide level and 92.4％-99.6％ at amino acid level with other DHAV-1 strains.There were three hypervariable regions at the C-terminus(as 158-160,180-193 and 205-219) and other variable points in VPI protein,but which didn't cause virulence of DHAV-1 change.
