Research And Application On The Immune Effect Of Medium-chain Fatty Acid Triglyceride As The Immunoadjuvant

Because of the development of vaccine becoming increasingly complex, it puts forwardhigher requirements on adjuvant. The improvements and innovations of the adjuvantmanufacturing technology, such as slowing antigen’s release rate, extending the immune validof the vaccine, and making the vaccine (for human and veterinary) more effective and safer,are the key areas of the world’s leading vaccine manufacturers’ research and development.Therefore, to explore the adjuvant, which not only gives play to the enhancement of immuneefficacy, but also carries antigen and improves antigenic activity, is of great significance forthe research progress of novel adjuvant.This thesis aims to find the new immunoadjuvant with high efficiency, quick result, lowtoxicity, and no adverse reactions. Basing on the preliminary research on the medium-chainfatty acid triglyceride (MCT) as adjuvant, the researcher explored the effects of MCT onchicken’s antibody titers variation, T lymphocyte proliferation changes, the lymphocytesecretion of cytokines IL-2, IL-6and IFN-γ, changes in the immune organs, and the growthperformance of chicken, after immune vaccine with Newcastle disease(ND), avian infectiousbronchitis(IB) or avian influenza(AI), and compared with the conventional mineral oiladjuvant. Then, the researcher systematically studied the safety, toxicology and immunizationeffectiveness of combined Newcastle disease, infectious bronchitis and avianinfluenza(ND-IB-AI) inactivated vaccine which prepared with MCT adjuvant. Finally, theresearcher preliminary study the immune effects of the MCT added different immunesynergist. The studies include the following aspects:1、The preliminary study on vaccine immunization effect of MCT adjuvant on Newcastledisease, chicken bronchitis, and avian influenza. The aim of this research is to explore theeffects of antibody titer levels as well as the immune reactions in chicken after immunedifferent inactivated vaccine with MCT adjuvant of ND, IB or AI. After the immune, wetested the level of antibody titers in chicken using hemagglutination inhibition assay, thedynamic proliferation of T lymphocytes in peripheral blood with MTT assay, the effects oflymphocytes secrete cytokines IL-2，IL-6，and IFN-γ with double-antibody sandwich ELISAassay, and the influence on the growth performance of chickens by calculating feedconversion, respectively.2、The safety and toxicology studies of the combined ND-IB-AI inactivated vaccine withMCT adjuvant. The studies include safety trials in a single dose vaccination with different pathways on minimum age target animals after inoculating combined ND-IB-AI inactivatedvaccine; safety trials on non-used age target animals after inoculating combined ND-IB-AIinactivated vaccine; safety trials of a single dose vaccination, single dose repeated vaccinationand a super-dose vaccination on target animal after inoculating combined ND-IB-AIinactivated vaccine; the immunology effect on chickens as well as acute toxicity tests onchickens after inoculating combined ND-IB-AI inactivated vaccine.3、The immune effectiveness research of the combined ND-IB-AI inactivated vaccine withMCT adjuvant. The studies include immune trials after inoculating combined ND-IB-AIinactivated vaccine; the effectiveness on the chicken in different immune pathway afterinoculating combined ND-IB-AI inactivated vaccine; minimum immune dose trials afterinoculating combined ND-IB-AI inactivated vaccine; study of the effectiveness of serologicaltesting and correlation of the target animal immune challenge protection results afterinoculating combined ND-IB-AI inactivated vaccine; study on dynamics of antibodies afterinoculating combined ND-IB-AI inactivated vaccine; study on determination of vaccinatedbreeders offspring of maternal antibodies and challenge protection test after inoculatingcombined ND-IB-AI inactivated vaccine.4、The research on immune function of MCT adjuvant added squalene or Sargassum pallidumpolysaccharides. Experiment was conducted to compare the tests in which the chicken wasinoculated the ND or AI(H5N1or H911) inactivated vaccines using MCT adjuvant addedsqualene or Sargassum pallidum polysaccharide. After inoculating the ND or AI(H5N1or H911) inactivated vaccines, we tested the level of antibody titers in chicken usinghemagglutination inhibition assay, the dynamic proliferation of T lymphocytes in peripheralblood with MTT assay, the effects of lymphocytes secrete cytokines IL-2，IL-6，and IFN-γwith double-antibody sandwich ELISA assay, and the influence on the growth performance ofchickens by calculating feed conversion, respectively.This paper used MCT emulsion system in vaccine adjuvant system to achieve the idealpurpose of rapid immunity and lasting immune effect. Meanwhile, the use of natural oilsinstead of mineral oil in vaccine, can reduce the side effects of vaccine, improve the meatquality, and then can be actually used in laying hens and broiler breeding to achieve goodeconomic and social benefits. The research provides a theoretical basis for MCT used asanimal adjuvant.