title: Attenuated Salmonella Typhimurium delivery of a novel DNA vaccine induces immune responses and provides protection against duck enteritis virus.
abstract: DNA vaccines are widely used to prevent and treat infectious diseases, cancer and autoimmune diseases; however, their relatively low immunogenicity is an obstacle to their use. In this study, we constructed a novel and universal DNA vaccine vector (pSS898) that can be used to build DNA vaccines against duck enteritis virus (DEV) and other viruses that require DNA vaccines to provide protection. This vaccine vector has many advantages, including innate immunogenicity, efficient nuclear trafficking and resistance to attack from nucleases. UL24 and tgB from DEV were chosen as the antigens, and the heat labile enterotoxin B subunit (LTB) from Escherichia coli and the IL-2 gene (DuIL-2) from duck were used as adjuvants for the construction of DNA vaccine plasmids. Ducklings that were orally immunized with S739 (Salmonella Typhimurium Δasd-66 Δcrp-24 Δcya-25) and harboring these DEV DNA vaccines produced strong mucosal and systemic immune responses, and they resisted an otherwise lethal DEV challenge. More importantly, S739 (UL24-LTB) provided 90% protection after a priming-boost immunization. This study shows that our novel and universal DNA vaccine vector can be used efficiently in practical applications and may provide a promising method of orally inoculating ducks with a DEV DNA vaccine delivered by attenuated Salmonella Typhimurium for prevention of DVE.
authors.affiliation: Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
authors.forename: Xueyan
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Bioengineering, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China. Electronic address: qing.liu.2@sicau.edu.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
authors.forename: Kangpeng
authors.initials: K
authors.lastname: Xiao
authors.affiliation: Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Li
authors.affiliation: Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Institute of Preventive Veterinary Medicine, College of Veterinary Medicine, Sichuan Agricultural University, Chengdu, Sichuan 611130, China. Electronic address: qingkiki@163.com.
authors.forename: Qingke
authors.initials: Q
authors.lastname: Kong
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000956:Antigens, Viral / Q000276:immunology; D019556:COS Cells; D002522:Chlorocebus aethiops; D004372:Ducks / Q000235:genetics / Q000276:immunology* / Q000821:virology; D004926:Escherichia coli / Q000235:genetics; D005822:Genetic Vectors / Q000235:genetics / Q000276:immunology; D006566:Herpesviridae Infections / Q000276:immunology / Q000401:mortality / Q000517:prevention & control / Q000662:veterinary*; D018928:Immunity, Mucosal / Q000276:immunology; D025922:Mardivirus / Q000276:immunology; D011201:Poultry Diseases / Q000276:immunology / Q000401:mortality / Q000517:prevention & control* / Q000821:virology; D012486:Salmonella typhimurium / Q000276:immunology*; D016019:Survival Analysis; D014611:Vaccination / Q000379:methods*; D019444:Vaccines, DNA; D014765:Viral Vaccines / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D019444:Vaccines, DNA; D014765:Viral Vaccines
keywords: Attenuated Salmonella; DNA vaccine vector; DNA vaccines; Duck enteritis virus; Oral immunization