The immune enhancement effects of recombinant NDV expressing chicken granulocyte-macrophage colony-stimulating factor on the different avian influenza vaccine subtypes

Abstract

Avian influenza is an acute and highly contagious infectious disease that is caused by the influenza virus. Avian influenza has been widely spread all over the world, has caused property loss and has threatened human life and security. In this study, the recombinant plasmid rClone30‐chGM‐CSF was constructed and rescued to the recombinant virus rClone30‐chGM‐CSF successfully. After 8 days of immunization with the recombinant virus, the titre of NDV HI (haemagglutination inhibition) antibodies in SPF chickens reached its peak. The average titre of the rClone30‐chGM‐CSF group reached 6 log2 and was significantly higher than the protection critical value of 4 log2; the titres of the rClone30 group and the blank group were 2.86 log2 and 1 log2, respectively, indicating that the recombinant virus can effectively improve the NDV antibody titre. Then, SPF chickens were co‐immunized with the recombinant virus and with three different vaccine subtypes of inactivated avian influenza. The results indicated that the SPF chickens that were immunized with the vaccine plus rClone30‐chGM‐CSF showed significantly higher avian influenza antibody levels than those in the single vaccine groups. Furthermore, the SPF chickens in the vaccine plus rClone30‐chGM‐CSF group elicited stronger CD4+ and CD8+ T‐cell proliferative responses and also had upregulated transcriptional levels of interleukin‐1β (IL‐1β), IL‐4, IL‐6 and IL‐17 compared with those in the single vaccine groups. This study has shown that the recombinant virus expressing chicken granulocyte‐macrophage colony‐stimulating factor (chGM‐CSF) can be used not only as an NDV vaccine to effectively improve the titre of NDV antibodies but also as a biological adjuvant to enhance the immune effects of the avian influenza vaccine. Therefore, this recombinant virus can also be used as a biological adjuvant for other poultry vaccines.

Simultaneous Expression of Chicken Granulocyte Monocyte Colony-Stimulating Factor and the Hemagglutinin-Neuraminidase Epitope of the Virulent Newcastle Disease Virus Genotype VII C22 Strain in a Functional Synthetic Recombinant Adenovirus as a Genotype-Matched Vaccine with Potential Antiviral Activity

“…6 ) in vivo . According to recent studies, using ChGM-CSF as a bio-adjuvant enhanced the kinetics and quantity of the chicken antibody immunological response ( 1 , 55 – 58 ). The spread of ND can be prevented through immunizations, proper management, and biosecurity.…”

“…Previous results support our findings that ChIL-18 increased Th1-IFN-γ and Th2-IL-4 secretion, T and B lymphocyte proliferation, HI antibody titers, and ratios of CD4 + to CD8 + in chickens ( 71 , 72 ). Also, a single dose of ChGM-CSF fused or combined with spike glycoprotein (S1) of infectious bronchitis virus (IBV) in ovo vaccination boosted humoral and cellular immunity ( 58 ); in addition, the chickens in the rClone30-chGM-CSF-immunized group had higher CD4 + and CD8 + T cell proliferative responses ( 56 ), and following a booster immunization with chicken ChGM-CSF, both Th1 and Th2 cytokines were increased ( 1 , 55 ). We also investigated which vaccines protected chickens against challenge, and the results revealed that 100% of the CC, wtAdv, and rAdv-ChGM-CSF groups developed severe NDV-specific clinical indications and viral shedding and died within 7 days.…”

“…In several live-vector or inactivated NDV vaccines, our research team used biological adjuvants, such as chicken granulocyte monocyte colony-stimulating factor (ChGM-CSF), chicken melanoma differentiation-associated protein 5 (MDA5), and chicken interferon (IFN)-stimulated gene 12-2 (ISG 12 [ 2 ]), which have been proven to improve the vaccine’s immunological effectiveness in chickens ( 1 , 53 – 55 ). ChGM-CSF is a potent cytokine that regulates the maturation of granulocytes and macrophages from hematopoietic progenitors as well as improving the mature immune system’s response to antigens ( 56 ). Furthermore, in a recent chicken vaccination trial in which ChGM-CSF was used as an adjuvant, the kinetics and magnitude of the antibody response improved ( 55 – 58 ).…”

“…ChGM-CSF is a potent cytokine that regulates the maturation of granulocytes and macrophages from hematopoietic progenitors as well as improving the mature immune system’s response to antigens ( 56 ). Furthermore, in a recent chicken vaccination trial in which ChGM-CSF was used as an adjuvant, the kinetics and magnitude of the antibody response improved ( 55 – 58 ).…”

Chicken ISG12(2) attenuates Newcastle disease virus and enhances the efficiency of Newcastle disease vaccine via activating immune pathways

“…NDV vectors expressing these cytokines induce high NDV HI titre and increase protection in chicken (Zhang et al., 2016). In addition, recombinant NDV expressing GM‐CSF not only increases immunogenicity of NDV vaccine, but also enhances immune effects of other avian vaccines (Guo et al., 2020). In this study, we demonstrated that, comparing LaSota strain, recombinant NDV LaSota expressing chicken ISG12(2) up‐regulated cytokines in spleens of immunized chickens.…”