Development and evaluation of a chicken embryo fibroblast cell culture based live attenuated Indian strain duck plague vaccine

Abstract

Duck plague (DP) is an acute, contagious and fatal disease, caused by duck enteritis virus (DEV), with worldwide distribution causing several outbreaks and posing severe economic losses. The present study was carried out with a goal of development of a live attenuated cell culture based DP vaccine using an Indian strain of DEV and evaluation of its safety, efficacy along with complete genome analysis. The live attenuated DP vaccine (DPvac/IVRI-19) was developed by serial propagation of a virulent isolate of DEV (DEV/India/IVRI-2016) in the chicken embryo fibroblast (CEF) primary cell culture. Adaptation of DEV in CEF cell culture was indicated by more rapid appearance of cytopathic effects (CPE) and gradual increase of virus titre, which reached up to 10^7.5 TCID₅₀/mL after 41 passages. The safety, immunogenicity and efficacy of the vaccine were determined by immunization trials in ducklings. The DPvac/IVRI-19 was found to be avirulent and completely safe in the ducklings. Further, the vaccine induced both humoral and cell mediated immune responses and afforded 100% protection against the virulent DEV challenge. A comparison of the whole genome of DPvac/IVRI-19 (MZ911871) and DEV/India/IVRI-2016 (MZ824102) revealed significant number of mutations, which might be associated with viral attenuation. Phylogenetic tree of DEV/India/IVRI-2016 revealed its evolutionary relationship with other DEV isolates, but it formed a separate cluster with certain unique mutations. Thus, with the proven safety and 100% efficacy, the DPvac/IVRI-19 is suitable for large scale production with precisely pure form of vaccine and has potential utility at national and global levels.

Keywords:

• Duck enteritis virus
• duck plague
• chicken embryo fibroblast
• cell culture attenuated vaccine
• safety
• efficacy
• complete genome analysis

Acknowledgements

The authors are highly thankful to the Director, ICAR-Indian Veterinary Research Institute and Indian Council of Agricultural Research for providing the funds and the facilities to carry out this work.

Author contributions statement

Satyabrata Dandapat: Conception and design, supervision, funding acquisition, investigation, interpretation of data, drafting and revising the manuscript; Suresh Bindu: Experiment design, investigation, analysis and interpretation of data, drafting and revision; Gaurav Kumar Sharma: Investigation, data analysis, manuscript editing; Sivasankar Panickan: Experiment design, data analysis, drafting and revision; Sukdeb Nandi: Investigation, manuscript editing; G. Saikumar; Conceptualization, manuscript editing; Kuldeep Dhama: Investigation, manuscript drafting and revision. All authors have final approval of the version of the manuscript to be published and that all authors agree to be accountable for all aspects of the work.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

The data that support the findings of this study are available in supplementary information or from the corresponding author upon reasonable request.

Additional information

Funding

This study was supported through an institute research project of ICAR-Indian Veterinary Research Institute, Izatnagar, funded by the Indian Council of Agricultural Research (ICAR), New Delhi, India.