title: Preparation and efficacy of Newcastle disease virus DNA vaccine encapsulated in PLGA nanoparticles.
abstract: BACKGROUND
  Although the Newcastle disease virus (NDV) inactivated vaccines and attenuated live vaccines have been used to prevent and control Newcastle disease (ND) for years, there are some disadvantages. Recently, newly developed DNA vaccines have the potential to overcome these disadvantages. The low delivery efficiency, however, hindered the application of DNA vaccines for ND in practice.
  
  
  RESULTS
  The eukaryotic expression plasmid pVAX1-F (o) DNA that expressed the F gene of NDV encapsulated in PLGA nanoparticles (pFNDV-PLGA-NPs) were prepared by a double emulsion-solvent evaporation method and optimal preparation conditions of the pFNDV-PLGA-NPs were determined. Under the optimal conditions, the pFNDV-PLGA-NPs were produced in good morphology and had high stability with a mean diameter of 433.5 ± 7.5 nm, with encapsulation efficiency of 91.8 ± 0.3% and a Zeta potential of +2.7 mV. Release assay in vitro showed that the fusion gene plasmid DNA could be sustainably released from the pFNDV-PLGA-NPs up to 93.14% of the total amount. Cell transfection test indicated that the vaccine expressed and maintained its bioactivity. Immunization results showed that better immune responses of SPF chickens immunized with the pFNDV-PLGA-NPs were induced compared to the chickens immunized with the DNA vaccine alone. In addition, the safety of mucosal immunity delivery system of the pFNDV-PLGA-NPs was also tested in an in vitro cytotoxicity assay.
  
  
  CONCLUSIONS
  The pFNDV-PLGA-NPs could induce stronger cellular, humoral, and mucosal immune responses and reached the sustained release effect. These results laid a foundation for further development of vaccines and drugs in PLGA nanoparticles.
authors.affiliation: Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin, China ; Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Zhao
authors.affiliation: Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin, China ; Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin, China ; Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Huang
authors.affiliation: Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin, China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Luo
authors.affiliation: Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin, China ; Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Laboratory of Microbiology, College of Life Science, Heilongjiang University, Harbin, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Guo
authors.affiliation: Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion, Heilongjiang University, Harbin, China.
authors.forename: Chunxiao
authors.initials: C
authors.lastname: Dai
authors.affiliation: Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion, Heilongjiang University, Harbin, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Jin
authors.affiliation: Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Cui
authors.affiliation: Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, CAAS, Harbin, China.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D002645:Chickens / Q000276:immunology / Q000821:virology; D004337:Drug Carriers; D019344:Lactic Acid; D053758:Nanoparticles; D009521:Newcastle Disease; D009522:Newcastle disease virus / Q000235:genetics / Q000276:immunology*; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011201:Poultry Diseases / Q000517:prevention & control*; D019444:Vaccines, DNA / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D004337:Drug Carriers; D019444:Vaccines, DNA; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid