Study On The Immune-enhancing Effects Of Recombinant Chicken Interleukin-6(rChIL-6) Protein In Vivo

Immunosuppressive diseases cause enormous losses of poultry industry,while theresearch and development of genetic engineering immunoenhancer could effectivelyprevent and treat this phenomenon. On the basis of the successful research of geneengineering recombinant Chicken interleukin6(rChIL-6) protein, this study investedthe immunopotentiation of the rChIL-6protein to Infectious bursal disease virus (IBD)inactivated vaccine and inactivated Newcastle disease(ND) vaccine in vivo, revealedits mechanism of immunopotentiation on the level of the humoral and cellularimmunity and lay the clinical development foundation of the genetic engineeringimmunopotentiator based on rChIL-6protein.Using the indirect ELISA to measure the immunoreactivity of rChIL-6proteinreacting with monoclonal antibody against rChIL-6.Using the MTS to determine theactivity of rChIL-6protein Promoting the spleen lymphocytes and peripheral blood Tlymphocyte proliferation.6040-day-old SPF chickens were randomly divided into6groups and dealed with rChIL-6protein and IBD inactivated vaccine immunization byIntranasal instillation or intramuscular injection at the age of50days, and then UseELISA to test the IBDV antibody levels in serum and cytokine expression level of6groups of chicken before and after immunization for selecting the best immunizationroute and different cytokines expression level,select rChIL-6proteins play in the bodythe use of the action and the best way.807-day-old SPF chickens were randomlydivided into8groups and injected with rChIL-6protein and IBD inactivated vaccineand ND inactivated vaccine at the age of14days for further study.Using ELISA totest IBDV and NDV antibody level in serum、different cytokine expression level、theactivity of spleen lymphocytes and peripheral blood T lymphocyte proliferation andThe peripheral blood T lymphocyte subsets ratio to reveal the enhancementmechanism of immune by rChIL-6protein. The results show rChIL-6protein has a specific immune reaction with anti ChIL-6monoclonal antibody, rChIL-6protein can obviously promote splenic lymphocyteproliferation of chicken,when it diluted1:2~9with slight promote PBLC proliferationactivity. DPI21, the use of intramuscular injection, intranasal use of eye rChIL-6protein in the experimental group (group5and6) of IBDV antibody levels weresignificantly higher than IBDV vaccine group (p <0.01), and the fifth group wassignificantly higher than that of Group6(p <0.01); DPI7~28, No.5,6groups ChIL-4, ChIL-2, ChIFN-α, ChIFN-γ expression level was significantly higher than the othergroups (p <0.01), and the fifth group was significantly higher than Group6(p <0.01),DPI7~14, the fifth and sixth groups ChIL-6expression level was significantly higherthan the other groups (p <0.01), and the fifth group was significantly higher than thefirst six groups (p <0.01); above indicates use of the intramuscular route using rChIL-6protein inactivated IBDV vaccine enhancement eye than intranasal route.DPI7-49after immunization, the IBD antibody level in the serum of chicken of rChIL-6proteinand IBD inactivated vaccine immunity group were significantly higher than that ofIBD inactivated vaccine group （p＜0.01）. Interleukin-2,4,6(ChIL-2,ChIL-4,ChIL-6) and Interferon R (ChIFN-r) and etc. The expression levels of4cytokines weresignificantly higher than that of others（p＜0.01）. But the expression levels ofinterferon α (ChIFN-α) is not （p＜0.01）. The proliferation activity of spleenlymphocytes were significantly higher than other experimental groups（p＜0.01）.7-12d after immunization, Peripheral blood T lymphocyte proliferation activity wasslightly higher than that of other experimental groups（p＞0.05）. Result of IBDVon FCM:After DPI7,the4group’s percentage composition of Th、Tc cells both havea significant increase and reach the peak,while The CD4+/CD8+ratio is greater thanthe other groups at this time but lower than other groups at other time.This Suggeststhat rChIL-6protein can strengthen the cellular immunity ability.Conclusion: rChIL-6protein can have specific immune reaction with monoclonalantibody against rChIL-6in vitro, and has significant function to promote the activitySplenic lymphocyte proliferation and a slight function to promote peripheral blood Tlymphocyte proliferation. Use rChIL-6protein by intramuscular injection has the bestimmune enhancement effect. rChIL-6protein can obviously enhance the immuneantibody level of Chicken infectious bursal disease vaccine and Newcastle disease attenuated live vaccine and appropriately extend the time reach the peak bysignificantly enhance the humoral and cellular immune responses in chickens、Promote T, B lymphocyte proliferation and improve The ratio of CD4+/CD8+. thisstudy lay the foundation for the further study on the genetic engineeringimmunopotentiator based on rChIL-6protein.