Effect Of Resveratrol On Immune Response To Pseudorabies Virus Vaccine And Its Mechanism

Pseudorabies virus(PRV)is a herpes virus that can infect livestock and wild animals.Piglets are the main host and source of infection.It will reach 100%mortality when piglets infected with the virus.There are no special therapeutic drugs,and the vaccination is the most effective method.However,due to the mutations in the virus cause increased virulence and the low natural immunity of individual animals,vaccination often fails.Previous studies have shown that the success rates can be improved by the combination of the appropriate immune enhancers.Our laboratory research showed that Resveratrol(Res)has immunomodulation activity.In this study,mice were selected as the experimental animals,and the effect of Res on the immune efficacy of PRV vaccine was evaluated in vivo by visceral index,spleen tissue section,T lymphocyte subsets in serum,splenic lymphocyte proliferation,immune-related antibodies and cytokines;on this basis,peritoneal macrophages of immunized mice were extracted and the spleen were collected to evaluate the effects of Res on macrophage function and TLR4/NF-κBp65/JNK signaling pathway in vitro.The followings are the main results of this study:1 Effect of resveratrol on immune response of mice inoculated with PRV vaccineIn vivo evaluation of the effect of Res on the immune response ability of mice inoculated with PRV vaccine.Methods:Female BALB/c mice at 6 weeks of age were randomly divided into 6 groups.Including blank control group,vaccine group,astragalus polysaccharide-treated group,and resveratrol-treated groups.Res and APS were orally administered for 4 d,and the BL and VC groups were administered with equal volume of normal saline.0.2 m L of PRV vaccine was injected subcutaneously at 24 h after the end of gavage.on the 14th d,repeated the above method.And take samples on the 25th d.Results:Compared with the vaccine group,Res increased the number of Langerhans cells in spleen and thymic corpuscle in thymus,significantly increased the value of CD8~+T cell and the lymphocyte proliferation,the concentrations of IgG and IgG2a,the levels of immunocytokines in spleen and serum were significantly increased.Compared with the APS group,medium-dose Res increased the number of Langerhans cells in spleen and thymic corpuscle in thymus,significantly increased the levels of IgG and IgG2a in serum,and IL-2 m RNA in spleen,and IL-10 in serum.Conclusion:Medium-dose Res could effectively enhance the immune efficiency of PRV vaccine,thus improving the immune response ability of immunized mice,and the effect was better than APS.2 Effect of resveratrol on the function of peritoneal macrophages in immunized miceIn order to explore the mechanism of Res enhancing immune efficacy of PRV vaccine,this study extracted peritoneal macrophages from immunized mice and evaluated the effects on phagocytic killing function and antigen presenting ability of macrophages in vitro.Methods:The chicken erythrocyte phagocytosis test was used to detect the percentage of phagocytic cells(PP)and phagocytic index(PI)of peritoneal macrophages;then the levels of lysozyme and acid phosphatase which were secreted by peritoneal macrophages were analyzed by ELISA kits;finally,the expressions of CD80 and CD86m RNA were detected by RT-PCR,and the levels of CD80,CD86,and MHC-II were measured by flow cytometry.Results:Compared with the vaccine group,Res could significantly improve the PP and PI,and the concentrations of lysozyme;The m RNA expressions of CD80 and CD86,and the levels of CD86 and MHC-II were significantly increased.Compared with the APS group,medium-dose Res significantly increased the PP and the levels of CD86 and MHC-Ⅱ.Conclusion:Res enhanced the immune efficiency of PRV vaccine by elevating the phagocytic killing ability and antigen presentation function of macrophages,and the effect was better than APS.3 Effect of resveratrol on TLR4/NF-κBp65/JNK signal pathway in spleen of immunized micePrevious research found that the immunocytokines secreted by the spleen of the Res group increased significantly.Studies have shown that the secretion of cytokines is regulated by signaling pathways.Therefore,we attempt to investigate the mechanism of Res enhancing the immune efficacy of vaccines from the signal pathway.Methods:Western Blot was used to detect the expressions of the related proteins on the TLR4/NF-κBp65/JNK pathway in spleen of immunized mice.Results:Compared with the vaccine group,Res significantly upregulated the levels of TLR4,IKK,NF-κBp65,JNK,and p-JNK,and significantly downregulated the level of IκBα.Compared with the APS group,medium-dose Res significantly upregulated the levels of TLR4,NF-κBp65,JNK,and p-JNK,and significantly downregulated the level of IκBα.Conclusion:Res enhanced the immune efficiency of PRV vaccine by activating the TLR4/NF-κBp65/JNK signal pathways,and the effect was better than APS.In conclusion,resveratrol,as an immune enhancer of PRV vaccine,could enhance immune efficiency of PRV vaccine by improving the function of immune organs,increasing the value of CD8~+T cell,the rates of spleen T lymphocyte,the levels of immune-related antibody and cytokine in immune mice.The mechanisms were the enhancement of phagocytic killing ability and antigen presentation function of macrophages and activation of TLR4/NF-κBp65/JNK signaling pathways.