Interleukin-18 (IL-18) is an important cytokine involved in innate and acquired immunity. In this study, we cloned the fulllength chicken IL-18 (ChIL-18) gene from specific-pathogen-free (SPF) chicken embryo spleen cells and provided evidence that the ChIL-18 gene in a recombinant plasmid was successfully expressed in chicken DT40 cells. ChIL-18 significantly enhanced gamma interferon (IFN-␥) mRNA expression in chicken splenocytes, which increased IFN-␥-induced nitric oxide (NO) synthesis by macrophages. The potential genetic adjuvant activity of the ChIL-18 plasmid was examined in chickens by coinjecting ChIL-18 plasmid and inactivated Newcastle disease virus (NDV) vaccine. ChIL-18 markedly elevated serum hemagglutination inhibition (HI) titers and anti-hemagglutinin-neuraminidase (anti-HN)-specific antibody levels, induced the secretion of both Th1-(IFN-␥) and Th2-(interleukin-4) type cytokines, promoted the proliferation of T and B lymphocytes, and increased the populations of CD3؉ T cells and their subsets, CD3 ؉ CD4 ؉ and CD3 ؉ CD8 ؉ T cells. Furthermore, a virus challenge revealed that ChIL-18 contributed to protection against Newcastle disease virus challenge. Taken together, our data indicate that the coadministration of ChIL-18 plasmid and NDV vaccine induces a strong immune response at both the humoral and cellular levels and that ChIL-18 is a novel immunoadjuvant suitable for NDV vaccination. N ewcastle disease (ND) is a serious avian disease that causes substantial economic loss and remains a major threat to the poultry industry (1, 2). Outbreaks of ND among poultry occur worldwide, and the pathogenic form of the virus is a disease listed in the World Organization for Animal Health (OIE) Terrestrial Animal Health Code and must be reported to the OIE (3), which results in severe trade limitations (4, 5). Currently, vaccination is the major tool for controlling infection by Newcastle disease virus (NDV). The NDV vaccine strains LaSota, B1, Mukteswar, and V4 are used widely in China. However, virulent NDV strains are still frequently isolated in vaccinated birds, indicating that NDV remains an ongoing threat to commercial flocks of birds (6). Therefore, it is necessary to develop more efficacious vaccines to prevent NDV infection.Many techniques have been developed to increase the immunogenicity of vaccines. Among these, cytokines are effective immunomodulators in animal models or in clinical testing (7-10). Among the large number of cytokines, interleukin-18 (IL-18) is a strong stimulator of T helper type 1 (Th1) responses and activates natural killer (NK) cells, stimulates the synthesis of other immunoactive cytokines from Th1 cells, monocytes, and NK cells, and synergizes with IL-12 in the maturation of Th1 cells and the suppression of IgE synthesis by B cells (11-13). Thus, IL-18 functions as an adjuvant (14, 15). However, depending on the cytokine environment, IL-18 may also promote Th2-type responses (16,17) and antibody formation (18).The isolation and characterization of chicken IL-18 (ChIL-18) ...
Background: Marek's disease (MD) is caused by the oncogenic Marek's disease virus (MDV), and is a highly contagious avian infection with a complex underlying pathology that involves lymphoproliferative neoplasm formation. MicroRNAs (miRNAs) act as oncogenes or tumor suppressors in most cancers. The gga-miR-155 is downregulated in the MDV-infected chicken tissues or lymphocyte lines, although its exact role in tumorigenesis remains unclear. The aim of this study was to analyze the effects of gga-miR-155 on the proliferation, apoptosis and invasiveness of an MDV-transformed lymphocyte line MSB1 and elucidate the underlying mechanisms. Results: The expression level of gga-miR-155 was manipulated in MSB1 cells using specific mimics and inhibitors. While overexpression of gga-miR-155 increased proliferation, decreased the proportion of G1 phase cells relative to that in S and G2 phases, reduced apoptosis rates and increased invasiveness. However, its downregulation had the opposite effects. Furthermore, gga-miR-155 directly targeted the RORA gene and downregulated its expression in the MSB1 cells. Conclusion: The gga-miR-155 promotes the proliferation and invasiveness of the MDV-transformed lymphocyte line MSB1 and inhibits apoptosis by targeting the RORA gene.
In summary, our results suggest that the recombinant SS OCT protein, which is involved in bacterial adherence, may efficiently stimulate an immune response conferring protection against SS infections. It may therefore be considered as a potential vaccine candidate, although further studies are necessary to evaluate their use in swine.
Newcastle disease virus (NDV) and Salmonella Pullorum have significant damaging effects on the poultry industry, but no previous vaccine can protect poultry effectively. In this study, a recombinant-attenuated S. Pullorum strain secreting the NDV hemagglutinin-neuraminidase (HN) protein, C79-13ΔcrpΔasd (pYA-HN), was constructed by using the suicide plasmid pREasd-mediated bacteria homologous recombination method to form a new bivalent vaccine candidate against Newcastle disease (ND) and S. Pullorum disease (PD). The effect of this vaccine candidate was compared with those of the NDV LaSota and C79-13ΔcrpΔasd (pYA) strains. The serum hemagglutination inhibition antibody titers, serum immunoglobulin G (IgG) antibodies, secretory IgA, and stimulation index in lymphocyte proliferation were increased significantly more (p < 0.01) in chickens inoculated with C79-13ΔcrpΔasd (pYA-HN) than with C79-13ΔcrpΔasd (pYA) but were not significantly increased compared with the chickens immunized with the LaSota live vaccine (p > 0.05). Moreover, the novel strain provides 60% and 80% protective efficacy against the NDV virulent strain F48E9 and the S. Pullorum virulent strain C79-13. In summary, in this study, a recombinant-attenuated S. Pullorum strain secreting NDV HN protein was constructed. The generation of the S. Pullorum C79-13ΔcrpΔasd (pYA-HN) strain provides a foundation for the development of an effective living-vector double vaccine against ND and PD.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.