Article

Enhanced immune responses of mice inoculated recombinant adenoviruses expressing GP5 by fusion with GP3 and/or GP4 of PRRS virus.

Key Laboratory of Animal Diseases Diagnostic and Immunology, College of Veterinary Medicine, Nanjing Agricultural University, Ministry of Agriculture, Nanjing 210095, China.
Virus Research (impact factor: 2.94). 10/2008; 136(1-2):50-7. DOI:10.1016/j.virusres.2008.04.016
Source: PubMed

ABSTRACT Porcine reproductive and respiratory syndrome (PRRS) is one of the most important causes of economic losses of the swine industry. PRRS virus (PRRSV) infection poses a challenge to current vaccination strategies. In this study, three replication-defective adenovirus recombinants expressing fusion protein GP3-GP5, GP4-GP5, or GP3-GP4-GP5 were developed as potential vaccine against PRRSV in a mouse model. Six groups of BALB/c mice (24mice per group) were inoculated subcutaneously twice at 2-week intervals with above mentioned recombinants and other adenoviruses expressing single GP3, GP4, or GP5 protein. The results showed that the mice inoculated with recombinant adenoviruses developed PRRSV-specific antibodies, cellular immune response by 2 weeks post-boost-immunization. However, mice immunized with recombinant adenoviruses rAd-GP3-GP5, rAd-GP4-GP5, and rAd-GP3-GP4-GP5 developed significantly higher titers of neutralizing antibodies to PRRSV and produced stronger lymphocyte proliferation responses compared to mice immunized with rAd-GP3, rAd-GP4 or rAd-GP5 alone. It was also found that mice immunized with rAd-GP3-GP5 and rAd-GP3-GP4-GP5 were primed for significant higher levels of anti-PRRSV CTL responses than mice immunized with rAd-GP3 and rAd-GP5. These findings suggested that the recombinant adenoviruses expressing fusion proteins GP3-GP5 or GP3-GP4-GP5 might be an attractive candidate vaccine for preventing PRRSV infection.

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Keywords

2 weeks post-boost-immunization
 
anti-PRRSV CTL responses
 
cellular immune response
 
current vaccination strategies
 
fusion protein GP3-GP5
 
fusion proteins GP3-GP5
 
GP5 protein
 
higher titers
 
mouse model
 
Porcine reproductive
 
potential vaccine
 
PRRSV
 
PRRSV infection
 
PRRSV-specific antibodies
 
rAd-GP3-GP5
 
recombinant adenoviruses rAd-GP3-GP5
 
replication-defective adenovirus recombinants
 
respiratory syndrome
 
stronger lymphocyte proliferation responses
 
swine industry