Preparation of the inactivated Newcastle disease vaccine by plasma activated water and evaluation of its protection efficacy.

Vaccination has been regarded as the most effective way to reduce death and morbidity caused by infectious diseases in the livestock industry. In this study, plasma activated water (PAW) was introduced to prepare the inactivated Newcastle disease vaccine. Humoral immune response was tested by hemagglutination inhibition (HI) assay and enzyme-linked immunosorbent assay (ELISA). In addition, cell-mediated immune response was evaluated by lymphocyte proliferation assay and flow cytometry. The results demonstrated that the vaccine prepared by PAW at appropriate volume ratio could induce similar antibody titers in specific pathogen-free (SPF) chickens compared with the formaldehyde-inactivated vaccine. The challenge experiment further confirmed that the vaccine prepared by PAW conferred solid protection against virulent NDV. Moreover, it was found that the vaccine could promote the proliferation of lymphocytes and stimulate cell-mediated immunity of SPF chickens. Furthermore, analysis of electron spin resonance (ESR) spectroscopy and physicochemical properties of PAW suggested reactive oxygen and nitrogen species (RONS) played an essential role in the virus inactivation. Therefore, this study indicated that NDV treated by PAW in an appropriate ratio retained immunogenicity on the premise of virus inactivation. PAW as a promising strategy could be used to prepare inactivated vaccine for Newcastle disease.

Efficient Protection of H5N1 Influenza Virus DNA Vaccine Delivering by Electroporation in Mammalian and Avian System / 生物化学与生物物理进展

To investigate the protection effect of DNA vaccine in mammalian and avian systems, the DNA vaccine was inoculated in both BALB/c mice and SPF chickens immunized with DNA vaccines encoding hemagglutinin (HA) from A/Goose/GuangDong/1/96 (H5N1) virus. The mice and chickens were immunized twice, 3 weeks apart, by electroporation into muscles or intramuscular injection. Two weeks after the second immunization, the mice and chickens were challenged with a lethal dose of homologous virus. The mice and chickens immunized by electroporation obtained completely protection against the virus, and could effectively inhibited viruses to replicating in mouse lung and chicken cloaca. At the same time, these protections were companied by high levels specific antibody to H5N1 AIV, while the blank plasmid controls experience 100 percent mortality following challenge. Furthermore, in the experiment of mice by eletroporation,stronger obviously CTL activity were observed after challenge. Thus, the cellular immune responses of the mice immunized by electroporation were exhibited. These results strongly demonstrate that HA DNA vaccines provide effective protection against influenza virus infection in mammalian and avian, and suggest that electroporation is one of the efficient gene delivery systems for the transfer of influenza DNA vaccine in both humoral immunity and cellular immunity.