中国畜牧兽医 ›› 2025, Vol. 52 ›› Issue (9): 4284-4290.doi: 10.16431/j.cnki.1671-7236.2025.09.026

• 预防兽医 • 上一篇    

鸭甲肝病毒基因3型弱毒株与其返强毒株的生物学特性比较

胡晓阳1,2, 黄晶晶1,2, 彭铎1,2, 张大丙1,2   

  1. 1. 中国农业大学动物医学院, 兽医公共卫生安全全国重点实验室, 北京 100193;
    2. 中国农业大学动物医学院, 农业农村部动物流行病学重点实验室, 北京 100193
  • 收稿日期:2025-02-27 发布日期:2025-08-29
  • 通讯作者: 张大丙 E-mail:zdb@cau.edu.cn
  • 作者简介:胡晓阳,E-mail:b20193050430@cau.edu.cn。
  • 基金资助:
    国家现代农业产业技术体系(CARS-42-16)

Comparison of Biological Properties of Duck Hepatitis A Virus Genotype 3 Attenuated Strain and Its Reversion Strain

HU Xiaoyang1,2, HUANG Jingjing1,2, PENG Duo1,2, ZHANG Dabing1,2   

  1. 1. National Key Laboratory of Veterinary Public Health and Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China;
    2. Key Laboratory of Animal Epidemiology and Zoonoses of Ministry of Agriculture and Rual Affairs, College of Veterinary Medicine, China Agricultural University, Beijing 100193, China
  • Received:2025-02-27 Published:2025-08-29

摘要: 【目的】 探究鸭甲肝病毒基因3型(Duck hepatitis A virus genotype 3,DHAV-3)弱毒株毒力返强的机制,通过雏鸭试验和基因组序列分析对DHAV-3弱毒株与其返强毒株的生物学特性进行比较。【方法】 用DHAV-3分离株YDF的第140代鸡胚化弱毒株Y140及其第4代雏鸭传代毒株Y140/4R接种1日龄北京鸭,观察临床症状、病理变化、发病率和死亡率,用实时荧光定量PCR检测雏鸭肝脏、肾脏和血清中的病毒RNA水平。对Y140株及其第1~4代雏鸭传代病毒基因组序列进行测序分析,探究与毒力返强有关的分子机制。【结果】 接种Y140株的雏鸭均未出现临床症状和病理变化,接种Y140/4R株的雏鸭出现鸭病毒性肝炎的特征性临床症状和大体病变,死亡率为40%。与Y140株相比,Y140/4R株感染后3 d存活鸭肝脏和肾脏中病毒RNA水平显著升高(P<0.05),感染后2~3 d死亡鸭肝脏和肾脏中病毒RNA水平极显著升高(P<0.01)。感染后2~4 d,Y140/4R株产生的病毒血症水平显著高于Y140株(P<0.05)。基因组测序结果显示,从第2代开始,2C、3D蛋白和3'-非翻译区分别发生I149V、V236I和A25G突变;从第3代开始,VP1蛋白发生E202D突变。【结论】 雏鸭传代可驱动DHAV-3弱毒株基因组发生突变,导致毒力变异株出现,使病毒在靶器官的复制能力以及形成病毒血症的能力显著提高。

关键词: 鸭甲肝病毒基因3型(DHAV-3); 弱毒株; 毒力返强; 复制; 病毒血症

Abstract: 【Objective】 The experiment was to explore the mechanism of virulence reversion of Duck hepatitis A virus genotype 3 (DHAV-3) attenuated strain.The biological characteristics of the DHAV-3 attenuated strain and its revertant strain were compared through ducklings experiments and genomic sequence analysis. 【Method】 One-day-old Pekin ducklings were inoculated with DHAV-3 attenuated strain Y140,derived by 140 passages of isolate YDF in chicken embryos,and its revertant strain Y140/4R,derived by 4 passages in duckings,and monitored for clinical signs,gross lesions,morbidity and mortality.Viral RNA levels in liver,kidney and serum of ducklings were measured by Real-time quantitative PCR.Sequencing and analysis were conducted on the genomic sequences of the Y140 strain and the first to fourth passage viruses of Y140 to explore the molecular mechanisms related to virulence reactivation. 【Result】 Ducklings inoculated with Y140 strain showed no clinical symptoms or pathological changes.Ducklings inoculated with Y140/4R strain presented the characteristic clinical symptoms and gross lesions of duck viral hepatitis,and the mortality was 40%.Compared with Y140 strain,the viral RNA levels in liver and kidney of surviving ducks 3 days after infection with Y140/4R strain were significantly increased (P<0.05),and the viral RNA levels in liver and kidney of dead ducks 2-3 days after infection were extremely significantly increased (P<0.01).2-4 days after infection,the viremia level produced by Y140/4R strain was significantly higher than that of Y140 strain (P<0.05). The genomic sequencing results showed that starting from the second generation,mutations I149V,V236I and A25G occurred in 2C protein,3D protein and 3'-UTR,respectively.Starting from the third generation,the E202D mutation occurred in VP1 protein. 【Conclusion】 Passage of duckings could drive mutations in the genome of DHAV-3 attenuated strain,leading to the emergence of virulence variants and significantly enhancing the replication ability of virus in target organs and the ability to form viremia.

Key words: Duck hepatitis A virus genotype 3 (DHAV-3); attenuated strain; reversion to virulence; replication; viremia

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