Effect Of Intranasal Immunization With Inactivated Avian Influenza Virus And Two Adjuvants On Chickens

Intranasal vaccination can directly cut off the route of transmission of the invasion of pathogenic microorganisms in animals, to induce local and systemic immune response. It is an effective method of immunization. Intranasal immunization with inactivated virus alone is often insufficient. However, intranasal immunization with inactivated virus plus adjuvant can induce protective immune response efficiently. In this study, chickens were immunized intranasally with inactivated avian influenza H9N2 virus (IAIV) plus with adjuvant 1 or adjuvant 2. Avian influenza virus specific hemagglutination inhibition (HI) antibody levels in serum and the protection rate was detected to evaluate the effect of the co-administration of IAIV and the two adjuvants on chickens. In addition, the effects of the live virus and inactivated virus of three strains:avian influenza virus (ATV), infectious bursal disease virus (IBDV) and infectious bronchitis virus (IBV) on the maturation of chicken bone marrow-derived dendritic cells (DCs) were investigated. According to comparison, the different stimulatory effects of these viruses on chicken bone marrow-derived DCs, the immune mechanism of the avian influenza virus was preliminarily investigated in vitro. The results were as follows. 1 The effect of intranasal immunization with inactivated avian influenza virus and two adjuvants on chickensIn this study,2003-day-old chickens were randomly divided into five groups. Group 1: intranasal immunization with IAIV and adjuvant 1. Group 2:intranasal immunization with IAIV and adjuvant 2. Group 3:intranasal immunization with IAIV. Group 4:intranasal immunization with IAIV oil emulsion vaccine intramuscularly. Group 5:intranasal immunization with PBS. After Immunization, blood from 10 chickens each group was obtained weekly for detecting the AIV-specific HI antibody levels in serum.10 chickens from each group were challenged intranasally with standard virulent avian influenza H9N2 (Beijing strain) respectively at the 7th,14th and 21st day, after the final immunization.The above results showed that the AIV-specific HI level and protection rate were all increased in the Group 1 and Group 2 compared with Group 3. The AIV-specific HI levels in the Group 1 and Group 2 were much higher than that in the Group 4 in the early period. In addition, the chickens in the Group 1 and Group 2 had 100% protective rate during the whole change test. These suggested that adjuvant 1 or adjuvant 2 could significantly enhance the immune effect of intranasal immunization with the avian influenza H9N2 inactivated virus. 2 The immunostimulatory activity of the live virus and inactivated virus of three strains on chicken marrow-derived dendritic cells.AIV, IBDV and IBV were purified and inactivated. The chicken bone marrow-derived DCs were cultured and stimulated respectively by live virus and inactivated virus of AIV, IBDV and IBV for 24h in vitro. Firstly, the chicken bone marrow-derived DCs maturation makers CD40, CD86 were detected by flow cytometry. Then, after the live virus and inactivated virus stimulation, the ability of induce allogeneic T cell proliferation was detected by WST-8 Cell Counting Kit-8 (CCK-8).The results showed that after stimulated by live virus and inactivated virus of AIV, IBDV and IBV, the expression levels of chicken CD40, CD86 molecules were increased. After the three inactivated virus stimulation, mature molecular markers CD40 and CD86 expression were higher than that stimulation by the live virus. Following AIV inactivated virus stimulation, chicken bone marrow-derived DCs maturation phenotype CD40 and CD86 expression level was the highest. Besides, the chicken bone marrow-derived DCs stimulated respectively by the live virus and inactivated virus of three stains could significantly induce allogeneic T cells proliferation (P<0.01). After the AIV inactivation stimulation, the ability of chicken bone marrow-derived DCs to induce allogeneic T cells proliferation was the best. The results indicated that the AIV inactivated virus could effectively induce the chicken bone marrow-derived DCs maturation.