Abstract:
Inactivated poultry vaccines are subject to routine potency testing for batch release, requiring large
numbers of animals. The replacement of in vivo tests for cell-based alternatives can be facilitated
by the identifcation of biomarkers for vaccine-induced immune responses. In this study, chicken
bone marrow-derived dendritic cells were stimulated with an inactivated vaccine for infectious
bronchitis virus and Newcastle disease virus, as well as inactivated infectious bronchitis virus only,
and lipopolysaccharides as positive control, or left unstimulated for comparison with the stimulated
samples. Next, the cells were lysed and subjected to proteomic analysis. Stimulation with the vaccine
resulted in 66 diferentially expressed proteins associated with mRNA translation, immune responses,
lipid metabolism and the proteasome. For the eight most signifcantly upregulated proteins, mRNA
expression levels were assessed. Markers that showed increased expression at both mRNA and protein
levels included PLIN2 and PSMB1. Stimulation with infectious bronchitis virus only resulted in 25
diferentially expressed proteins, which were mostly proteins containing Src homology 2 domains.
Stimulation with lipopolysaccharides resulted in 118 diferentially expressed proteins associated
with dendritic cell maturation and antimicrobial activity. This study provides leads to a better
understanding of the activation of dendritic cells by an inactivated poultry vaccine, and identifed
PLIN2 and PSMB1 as potential biomarkers for cell-based potency testing.
