The immune-adjuvant effect of Japanese flounder Paralichthys olivaceus IL-1β

IL-1 beta is known as a pro-inflammatory cytokine and plays a pivotal role in regulating immune response. IL-1 beta has been shown to influence immune responses in Japanese flounder Paralichthys olivaceus. To investigate the immune responses, a plasmid construct of pcDNA3.1-driven Japanese flounder IL-1 beta (pcDNA3.1-JFIL-1 beta) was co-injected into the muscle with Bovine serum albumin (BSA), as an antigen model, or pCI-neo driven with GFP (pCI-neo-GFP) as a vaccine model compared with the antigen or vaccine model alone, respectively. The IL-1 beta expression in the muscle was dramatically elevated in fish injected with pcDNA3.1-JFIL-1 beta on a day after injection, and the induction level was significantly higher than control groups. Moreover, pcDNA3.1-JFIL-1 beta significantly stimulated the gene expression of IL-1 beta in the kidney. The pcDNA3.1-JFIL-1 beta enhanced the antibody titer against BSA at 30 days after injection. In the DNA vaccine model, the antibody titer against GFP was also higher in the fish injected with pcDNA3.1-JFIL-1 beta than the group that injected pCI-neo-GFP alone. These results suggest that the pcDNA-driven Japanese flounder IL-1 beta could have potential immunoadjuvant effects. (C) 2013 Elsevier Ltd. All rights reserved.