Studies On Anti-idiotype Antibody Vaccine Of Chicken Infectious Bursal Disease

Infectious bursal disease (IBD) of chicken is one of the seriously infectious diseases thatdamage poultry industry.Vaccination of routine vaccines is the major means for control ofIBD. Though, they have some disadvantages inevitably, for example: inactivated vaccinescould result in potential infection due to survival viruses; all attenuated vaccines do harm tochicken bursas; the wide-ranging use of attenuated vaccines could hamper the control ofinfectious disease and cause alteration to virus virulence and antigenicity.Therefore, we havethe studies on anti-idiotype (anti-Id) antibody vaccine of IBD in order to avoid thesedisadvantages and develop a novel kind of safe vaccine, as well as establish the theoryfoundation for it's practical use in future.The multiclonal anti-Id antibody was prepared by means of traditional immunoserology.Attenuated D₇₈ strain of IBDV were propagated in chicken embryo fibroblasts cells (CEF) andpurified on a sucrose gradient. The specific-pathogen free (SPF) hens were immunized withthe purified viruses and the IBDV-specific yolk IgG (Ab1) were purified from the yolk withtrichloromathane degrease, sodium sulfate precipitation and DEAE₃₂ ion-exchange filtration.The rabbits were immunized with Ab1 and part of the rabbit serum containing ani-Id (Ab2)were salted out with (NH₄)₂SO₄, then anti-Id were purified with Sepharose-4B affinityfiltration.The purified anti-Id was detected with inhibition and competitive inhibition ELISA onimmunochemistry. The results indicated that anti-Id antibody could competitively combinedAb1 with antigen (IBDV), but also inhibit the combination between Ab1 and antigen, whichconfirmed that the purified anti-Id antibody actually carry antigen "internal image"-Ab2β.The anti-Id antibody confirm to immuno-chemical property of anti-idiotype antibodyBiological experiments of ami-Id antibody in vitro demonstrated that anti-Id antibodycould mimic IBDV combining neutralizing antibody of IBDV.Immune protective trial showedthat anti-Id vaccine induced anti-IBDV antibody and protected chicken against IBDV to someextent. The adjuvant affected its protective efficiency.In the study, protective ratio of Freund'sadjuvant (83.3%) is superior to that of common white oil adjuvant (61.5%), and protectiveratio of routine vaccine (80%) is better than that of anti-Id vaccine (69.5%) in overall.Postgraduate: LIU HuairanMajor: Prophylactic Veterinary ScienceSupervisor: Prof.LI Yijing...