Interleukin-8 holds promise to serve as a molecular adjuvant in DNA vaccination model against Streptococcus iniae infection in fish.
DNA vaccines had been widely used in animal models against various viral infections, while it was not so convincing for many infectious diseases especially bacterial disease in aquaculture. Interleukin-8(IL-8) as one of the CXC chemokines, its immunological role and adjuvant potential which had been proved in mammals were rarely reported in fish species. In this study, recombination plasmid pcDNA3.1/IL-8(pcIL-8) was conducted and the capacity of IL-8 as molecular adjuvant was explored from several aspects by co-injecting with a DNA vaccine encoding α-enolase(pcENO) against Streptococcus iniae infection in channel catfish. The results suggested that co-injection of pcIL-8 with DNA vaccine increased the innate immunity and specific antibody levels, as well as increased the immune-related genes involving in pro-inflammatory response, humoral and cellular immunity. Moreover, pcIL-8 enhanced the immunoprotection of pcENO with the relative percent survival(RPS) of 60% to 80% against S.iniae infection at 4 week post vaccination(p.v.), with the significantly higher RPS of 73.33% in pcENO+pcIL-8 group compared with that of pcENO alone(53.33%) at challenge test of 8 weeks p.v. Taken together, these results indicate pcIL-8 as a molecular adjuvant co-injected with DNA vaccine not only improves the immunoprotection but also maintains long period of immunity for channel catfish against S.iniae infection. Our study signifies that IL-8 holds promise to serve as a potential adjuvant in DNA vaccines against bacterial infections for long time.
['Wang|Erlong|E|', 'Long|Bo|B|', 'Wang|Kaiyu|K|', 'Wang|Jun|J|', 'He|Yang|Y|', 'Wang|Xingli|X|', 'Yang|Qian|Q|', 'Liu|Tao|T|', 'Chen|Defang|D|', 'Geng|Yi|Y|', 'Huang|Xiaoli|X|', 'Ouyang|Ping|P|', 'Lai|Weimin|W|']
D000818:Animals D017756:Aquaculture D005393:Fish Diseases D029941:Fish Proteins D054884:Host-Pathogen Interactions D007059:Ictaluridae D007111:Immunity, Cellular D056724:Immunity, Humoral D007113:Immunity, Innate D000071497:Immunogenicity, Vaccine D016209:Interleukin-8 D010751:Phosphopyruvate Hydratase D013290:Streptococcal Infections D000070058:Streptococcus iniae D013997:Time Factors D019444:Vaccines, DNA
interleukin-8 molecular adjuvant DNA vaccine bacterial diseases aquaculture Immunity Immune response Immunology and Microbiology Section