Immunization with a suicidal DNA vaccine expressing the E glycoprotein protects ducklings against duck Tembusu virus

Jingyu Tang,Yingqi Zhu,Mingyang Ding,Li Zhang,Zhuangli Bi,Dongdong Yin,Qiuhong Miao,Guijun Wang,Jie Zhu,Guangqing Liu

doi:10.1186/s12985-018-1053-0

Abstract

BackgroudDuck Tembusu virus (DTMUV), a pathogenic flavivirus, emerged in China since 2010 and causing huge economic loss in the Chinese poultry industry. Although several vaccines have been reported to control DTMUV disease, few effective vaccines are available and new outbreaks were continuously reported. Thus, it is urgently to develop a new effective vaccine for prevention of this disease.MethodsIn this study, a suicidal DNA vaccine based on a Semliki Forest virus (SFV) replicon and DTMUV E glycoprotein gene was constructed and the efficacy of this new vaccine was assessed according to humoral and cell-mediated immune responses as well as protection against the DTMUV challenge in ducklings.ResultsOur results showed that the recombinant SFV replicon highly expressed E glycoprotein in DEF cells. After intramuscular injection of this new DNA vaccine in ducklings, robust humoral and cellular immune responses were observed in all immunized ducklings. Moreover, all ducklings were protected against challenge with the virulent DTMUV AH-F10 strain.ConclusionsIn conclusion, we demonstrate that this suicidal DNA vaccine is a promising candidate facilitating the prevention of DTMUV infection.

Highlights

Since April 2010, outbreaks of infectious disease in ducks resulting from duck Tembusu virus (DTMUV) have reported throughout the main duck-producing regions of China [1, 2]
Expression of E glycoprotein in Duck embryo fibroblasts (DEF) cells To test whether the constructed plasmid could express E glycoprotein in vitro, DEF cells were transfected with individual plasmids and the expression of E glycoprotein was examined via IFA and western blot analyses
These data demonstrate that E glycoprotein can be highly expressed by pSCA1-E plasmid and retained its high immunoreactivity of the anti-E antibody in vitro

Summary

Introduction

Since April 2010, outbreaks of infectious disease in ducks resulting from duck Tembusu virus (DTMUV) have reported throughout the main duck-producing regions of China [1, 2]. Ducks infected with DTMUV often develop high fever, diarrhea, and weight loss, and exhibit retarded growth and decreased egg-laying [1,2,3]. Due to the highly contagious nature of this virus, DTMUV has resulted in huge economic losses in the duck industry. It has been reported that DTMUV has a wide host spectrum such as ducks, geese [8], chickens [9] and sparrows [10]. It is noteworthy that Tang et al reported DTMUV caused human infection and may be a zoonotic pathogen in China [11]. A safe and efficient vaccine be developed to prevent this disease is essential

Methods

Results

Conclusion