Immune adjuvant effects of interferon-gamma (IFN-γ) of flounder (Paralichthys olivaceus) against Edwardsiella tarda. (October 2021)

• Record Type: Journal Article
• Authors: Wang, Hongxiang; Guo, Ming; Tang, Xiaoqian; Xing, Jing; Sheng, Xiuzhen; Chi, Heng; Zhan, Wenbin
• Is Part Of: Developmental and comparative immunology. Volume 123(2021)
• Publication Date: 2021-10
• Subjects: Immune adjuvant -- Interferon-gamma -- Flounder -- Edwardsiella tarda -- OmpV; Immunology -- Periodicals; Developmental immunology -- Periodicals; 616.079
• DOI: 10.1016/j.dci.2021.104159
• Languages: English
• ISSNs: 0145-305X

Abstract

Abstract: IFN-γ plays a key role in T-cell activation and the establishment of the adaptive immune response, which has a potential as a cytokine adjuvant in the context of vaccination. In this study, we evaluated the immune adjuvant effects of two forms of flounder ( Paralichthys olivaceus ) IFN-γ, including pcDNA3.1-IFN-γ (pcIFN-γ) and recombinant IFN-γ (rIFN-γ), and comparatively analyzed the immune responses of flounder to E. tarda subunit vaccine rOmpV. The results showed that vaccination with rOmpV plus pcIFN-γ or rIFN-γ produced a relative percent survival of 57% and 71%, respectively, which were significantly higher than that of the control groups, rOmpV plus pcN3 (36%) or rHis (40%). Compared with the two control groups, vaccination with rOmpV plus pcIFN-γ or rIFN-γ could induce significantly higher levels of specific serum antibodies and sIg + lymphocytes in peripheral blood, spleen and head kidney, and significantly higher upregulated expressions of CD4-1, CD8α, IgM, MHC Ⅰα, MHC Ⅱα, IL-1β and TNF-α were also detected in rOmpV plus pcIFN-γ or rIFN-γ vaccinated fish. In addition, compared with pcIFN-γ, rOmpV co-vaccination with rIFN-γ elicited higher levels of sIg + lymphocytes, specific serum antibodies and several immune-related genes expressions in vaccinated flounder. These results demonstrated that rOmpV co-vaccination with rIFN-γ or pcIFN-γ could both boost the immune responses and evoke highly protective effects against E. tarda, indicating that flounder IFN-γ is a promising adjuvant candidate for fish vaccination via an injection administering route. Highlights: Flounder IFN-γ displayed strong adjuvant stimulatory activity. The rIFN-γ and pcIFN-γ both can enhance the immune protective efficacy of subunit vaccines rOmpV. Recombinant IFN-γ combined with rOmpV can elicit stronger immune response and confer higher RPS.